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Posted to notifications@shardingsphere.apache.org by du...@apache.org on 2022/05/15 15:08:39 UTC

[shardingsphere] branch master updated: Refactor new HashMap<>(1, 1) to Collections.singletonMap() (#17675)

This is an automated email from the ASF dual-hosted git repository.

duanzhengqiang pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/shardingsphere.git


The following commit(s) were added to refs/heads/master by this push:
     new 70b465ecafa Refactor new HashMap<>(1, 1) to Collections.singletonMap() (#17675)
70b465ecafa is described below

commit 70b465ecafa317a5c9b829e3e89318160ee7fcc1
Author: Liang Zhang <zh...@apache.org>
AuthorDate: Sun May 15 23:08:33 2022 +0800

    Refactor new HashMap<>(1, 1) to Collections.singletonMap() (#17675)
---
 .../framework/type/JDBCExampleScenario.java        |  2 +-
 .../type/SpringBootStarterJdbcExampleScenario.java |  9 ++----
 .../type/SpringBootStarterJpaExampleScenario.java  |  9 ++----
 .../SpringBootStarterMyBatisExampleScenario.java   | 10 ++----
 .../type/SpringNamespaceJdbcExampleScenario.java   |  9 ++----
 .../type/SpringNamespaceJpaExampleScenario.java    |  9 ++----
 .../SpringNamespaceMyBatisExampleScenario.java     | 12 +++----
 .../dbdiscovery/rule/DatabaseDiscoveryRule.java    |  5 ++-
 .../rule/DatabaseDiscoveryRuleTest.java            |  7 ++--
 ...tabaseDiscoveryHeartbeatQueryResultSetTest.java |  4 +--
 ...scoveryProviderAlgorithmQueryResultSetTest.java |  4 +--
 .../DatabaseDiscoveryRuleQueryResultSetTest.java   | 11 +++----
 ...pDatabaseDiscoveryRuleStatementUpdaterTest.java |  9 +++---
 .../impl/EncryptOrderByItemTokenGeneratorTest.java | 15 ++-------
 .../EncryptParameterRewriterBuilderTest.java       | 13 ++------
 .../DropEncryptRuleStatementUpdaterTest.java       |  7 ++--
 .../ReadwriteSplittingRuleQueryResultSetTest.java  | 18 ++---------
 ...ReadwriteSplittingRuleStatementUpdaterTest.java | 20 +++++-------
 .../dal/show/ShowCreateTableMergedResultTest.java  | 19 +++--------
 .../dal/show/ShowTableStatusMergedResultTest.java  | 23 ++++----------
 .../merge/dal/show/ShowTablesMergedResultTest.java | 37 ++++++++--------------
 .../CreateShardingScalingRuleStatementUpdater.java | 15 ++-------
 .../ShardingScalingRulesQueryResultSetTest.java    | 20 ++++--------
 .../engine/GeneratedKeyContextEngineTest.java      |  9 ++----
 .../YamlOnRuleAlteredActionConfiguration.java      |  2 +-
 .../pool/creator/DataSourcePoolCreatorTest.java    |  9 ++----
 .../fixture/MockedDataSourcePoolMetaData.java      |  4 +--
 .../schema/util/IndexMetaDataUtilTest.java         |  4 +--
 .../rewrite/context/SQLRewriteContextTest.java     | 19 ++++-------
 .../token/generator/SQLTokenGeneratorsTest.java    | 13 +++-----
 .../yaml/YamlShardingSphereDataSourceFactory.java  |  7 ++--
 .../ShardingSphereDatabaseMetaDataTest.java        |  2 +-
 .../singletable/rule/SingleTableRule.java          |  5 +--
 .../traffic/rule/TrafficRuleTest.java              | 30 +++++-------------
 .../ExportDatabaseConfigurationHandlerTest.java    |  9 ++----
 .../scenario/MixSQLRewriterParameterizedTest.java  |  8 ++---
 .../ShardingSQLRewriterParameterizedTest.java      |  8 ++---
 37 files changed, 122 insertions(+), 294 deletions(-)

diff --git a/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/JDBCExampleScenario.java b/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/JDBCExampleScenario.java
index 638b7e8ab42..710980af858 100644
--- a/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/JDBCExampleScenario.java
+++ b/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/JDBCExampleScenario.java
@@ -48,7 +48,7 @@ public final class JDBCExampleScenario implements FrameworkExampleScenario {
     
     @Override
     public Collection<String> getJavaClassPaths() {
-        Collection<String> result = new HashSet<>();
+        Collection<String> result = new HashSet<>(2, 1);
         result.add("config");
         result.add("repository");
         return result;
diff --git a/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringBootStarterJdbcExampleScenario.java b/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringBootStarterJdbcExampleScenario.java
index 2625787654d..812eb1b3b10 100644
--- a/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringBootStarterJdbcExampleScenario.java
+++ b/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringBootStarterJdbcExampleScenario.java
@@ -22,7 +22,6 @@ import org.apache.shardingsphere.example.generator.scenario.framework.FrameworkE
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
-import java.util.HashSet;
 import java.util.Map;
 
 /**
@@ -42,16 +41,12 @@ public final class SpringBootStarterJdbcExampleScenario implements FrameworkExam
     
     @Override
     public Map<String, String> getResourceTemplateMap() {
-        Map<String, String> result = new HashMap<>(1, 1);
-        result.put("resources/properties/application.ftl", "application.properties");
-        return result;
+        return Collections.singletonMap("resources/properties/application.ftl", "application.properties");
     }
     
     @Override
     public Collection<String> getJavaClassPaths() {
-        Collection<String> result = new HashSet<>();
-        result.add("repository");
-        return result;
+        return Collections.singleton("repository");
     }
     
     @Override
diff --git a/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringBootStarterJpaExampleScenario.java b/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringBootStarterJpaExampleScenario.java
index 01683ec2d1c..bd29497a2db 100644
--- a/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringBootStarterJpaExampleScenario.java
+++ b/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringBootStarterJpaExampleScenario.java
@@ -22,7 +22,6 @@ import org.apache.shardingsphere.example.generator.scenario.framework.FrameworkE
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
-import java.util.HashSet;
 import java.util.Map;
 
 /**
@@ -42,16 +41,12 @@ public final class SpringBootStarterJpaExampleScenario implements FrameworkExamp
     
     @Override
     public Map<String, String> getResourceTemplateMap() {
-        Map<String, String> result = new HashMap<>(1, 1);
-        result.put("resources/properties/application.ftl", "application.properties");
-        return result;
+        return Collections.singletonMap("resources/properties/application.ftl", "application.properties");
     }
     
     @Override
     public Collection<String> getJavaClassPaths() {
-        Collection<String> result = new HashSet<>();
-        result.add("repository");
-        return result;
+        return Collections.singleton("repository");
     }
     
     @Override
diff --git a/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringBootStarterMyBatisExampleScenario.java b/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringBootStarterMyBatisExampleScenario.java
index 953fca122d3..5513d3dd498 100644
--- a/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringBootStarterMyBatisExampleScenario.java
+++ b/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringBootStarterMyBatisExampleScenario.java
@@ -20,8 +20,8 @@ package org.apache.shardingsphere.example.generator.scenario.framework.type;
 import org.apache.shardingsphere.example.generator.scenario.framework.FrameworkExampleScenario;
 
 import java.util.Collection;
+import java.util.Collections;
 import java.util.HashMap;
-import java.util.HashSet;
 import java.util.Map;
 
 /**
@@ -51,16 +51,12 @@ public final class SpringBootStarterMyBatisExampleScenario implements FrameworkE
     
     @Override
     public Collection<String> getJavaClassPaths() {
-        Collection<String> result = new HashSet<>();
-        result.add("repository");
-        return result;
+        return Collections.singleton("repository");
     }
     
     @Override
     public Collection<String> getResourcePaths() {
-        Collection<String> result = new HashSet<>();
-        result.add("mappers");
-        return result;
+        return Collections.singleton("mappers");
     }
     
     @Override
diff --git a/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringNamespaceJdbcExampleScenario.java b/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringNamespaceJdbcExampleScenario.java
index e801b4ca441..39cfade0e50 100644
--- a/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringNamespaceJdbcExampleScenario.java
+++ b/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringNamespaceJdbcExampleScenario.java
@@ -22,7 +22,6 @@ import org.apache.shardingsphere.example.generator.scenario.framework.FrameworkE
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
-import java.util.HashSet;
 import java.util.Map;
 
 /**
@@ -42,16 +41,12 @@ public final class SpringNamespaceJdbcExampleScenario implements FrameworkExampl
     
     @Override
     public Map<String, String> getResourceTemplateMap() {
-        Map<String, String> result = new HashMap<>(1, 1);
-        result.put("resources/xml/application.ftl", "application.xml");
-        return result;
+        return Collections.singletonMap("resources/xml/application.ftl", "application.xml");
     }
     
     @Override
     public Collection<String> getJavaClassPaths() {
-        Collection<String> result = new HashSet<>();
-        result.add("repository");
-        return result;
+        return Collections.singleton("repository");
     }
     
     @Override
diff --git a/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringNamespaceJpaExampleScenario.java b/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringNamespaceJpaExampleScenario.java
index a76ef025b68..9e3ba642ec4 100644
--- a/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringNamespaceJpaExampleScenario.java
+++ b/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringNamespaceJpaExampleScenario.java
@@ -22,7 +22,6 @@ import org.apache.shardingsphere.example.generator.scenario.framework.FrameworkE
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
-import java.util.HashSet;
 import java.util.Map;
 
 /**
@@ -42,16 +41,12 @@ public final class SpringNamespaceJpaExampleScenario implements FrameworkExample
     
     @Override
     public Map<String, String> getResourceTemplateMap() {
-        Map<String, String> result = new HashMap<>(1, 1);
-        result.put("resources/xml/application.ftl", "application.xml");
-        return result;
+        return Collections.singletonMap("resources/xml/application.ftl", "application.xml");
     }
     
     @Override
     public Collection<String> getJavaClassPaths() {
-        Collection<String> result = new HashSet<>();
-        result.add("repository");
-        return result;
+        return Collections.singleton("repository");
     }
     
     @Override
diff --git a/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringNamespaceMyBatisExampleScenario.java b/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringNamespaceMyBatisExampleScenario.java
index daf301922fb..4adad5462c7 100644
--- a/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringNamespaceMyBatisExampleScenario.java
+++ b/examples/shardingsphere-example-generator/src/main/java/org/apache/shardingsphere/example/generator/scenario/framework/type/SpringNamespaceMyBatisExampleScenario.java
@@ -20,8 +20,8 @@ package org.apache.shardingsphere.example.generator.scenario.framework.type;
 import org.apache.shardingsphere.example.generator.scenario.framework.FrameworkExampleScenario;
 
 import java.util.Collection;
+import java.util.Collections;
 import java.util.HashMap;
-import java.util.HashSet;
 import java.util.Map;
 
 /**
@@ -41,7 +41,7 @@ public final class SpringNamespaceMyBatisExampleScenario implements FrameworkExa
     
     @Override
     public Map<String, String> getResourceTemplateMap() {
-        Map<String, String> result = new HashMap<>(1, 1);
+        Map<String, String> result = new HashMap<>(4, 1);
         result.put("resources/xml/application.ftl", "application.xml");
         result.put("resources/mappers/OrderItemMapper.ftl", "mappers/OrderItemMapper.xml");
         result.put("resources/mappers/OrderMapper.ftl", "mappers/OrderMapper.xml");
@@ -51,16 +51,12 @@ public final class SpringNamespaceMyBatisExampleScenario implements FrameworkExa
     
     @Override
     public Collection<String> getJavaClassPaths() {
-        Collection<String> result = new HashSet<>();
-        result.add("repository");
-        return result;
+        return Collections.singleton("repository");
     }
     
     @Override
     public Collection<String> getResourcePaths() {
-        Collection<String> result = new HashSet<>();
-        result.add("mappers");
-        return result;
+        return Collections.singleton("mappers");
     }
     
     @Override
diff --git a/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-core/src/main/java/org/apache/shardingsphere/dbdiscovery/rule/DatabaseDiscoveryRule.java b/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-core/src/main/java/org/apache/shardingsphere/dbdiscovery/rule/DatabaseDiscoveryRule.java
index 2881f7d3536..6e8eb1f760e 100644
--- a/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-core/src/main/java/org/apache/shardingsphere/dbdiscovery/rule/DatabaseDiscoveryRule.java
+++ b/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-core/src/main/java/org/apache/shardingsphere/dbdiscovery/rule/DatabaseDiscoveryRule.java
@@ -45,6 +45,7 @@ import org.apache.shardingsphere.schedule.core.api.ModeScheduleContextFactory;
 import javax.sql.DataSource;
 import java.sql.SQLException;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.Map;
@@ -168,9 +169,7 @@ public final class DatabaseDiscoveryRule implements SchemaRule, DataSourceContai
     
     @Override
     public Map<String, Supplier<Object>> getExportedMethods() {
-        Map<String, Supplier<Object>> result = new HashMap<>(1, 1);
-        result.put(ExportableConstants.EXPORTABLE_KEY_PRIMARY_DATA_SOURCE, this::exportPrimaryDataSourceMap);
-        return result;
+        return Collections.singletonMap(ExportableConstants.EXPORTABLE_KEY_PRIMARY_DATA_SOURCE, this::exportPrimaryDataSourceMap);
     }
     
     private Map<String, String> exportPrimaryDataSourceMap() {
diff --git a/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-core/src/test/java/org/apache/shardingsphere/dbdiscovery/rule/DatabaseDiscoveryRuleTest.java b/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-core/src/test/java/org/apache/shardingsphere/dbdiscovery/rule/DatabaseDiscoveryRuleTest.java
index 9d526263551..939b2d5ea63 100644
--- a/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-core/src/test/java/org/apache/shardingsphere/dbdiscovery/rule/DatabaseDiscoveryRuleTest.java
+++ b/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-core/src/test/java/org/apache/shardingsphere/dbdiscovery/rule/DatabaseDiscoveryRuleTest.java
@@ -32,7 +32,6 @@ import java.util.Collections;
 import java.util.Map;
 import java.util.Optional;
 import java.util.Properties;
-import java.util.HashMap;
 
 import static org.hamcrest.CoreMatchers.is;
 import static org.junit.Assert.assertThat;
@@ -71,15 +70,13 @@ public final class DatabaseDiscoveryRuleTest {
     @Test
     public void assertGetExportedMethods() {
         DatabaseDiscoveryRule databaseDiscoveryRule = createRule();
-        Map<String, String> singleDataSourceRuleMap = new HashMap<>(1, 1);
-        singleDataSourceRuleMap.put("test_pr", "primary");
-        assertThat(databaseDiscoveryRule.getExportedMethods().get(ExportableConstants.EXPORTABLE_KEY_PRIMARY_DATA_SOURCE).get(), is(singleDataSourceRuleMap));
+        assertThat(databaseDiscoveryRule.getExportedMethods().get(ExportableConstants.EXPORTABLE_KEY_PRIMARY_DATA_SOURCE).get(), is(Collections.singletonMap("test_pr", "primary")));
     }
     
     private DatabaseDiscoveryRule createRule() {
         DatabaseDiscoveryDataSourceRuleConfiguration config = new DatabaseDiscoveryDataSourceRuleConfiguration("test_pr", Arrays.asList("ds_0", "ds_1"), "", "CORE.FIXTURE");
         return new DatabaseDiscoveryRule("db_discovery", dataSourceMap, new DatabaseDiscoveryRuleConfiguration(
                 Collections.singleton(config), Collections.singletonMap("discovery_heartbeat", new DatabaseDiscoveryHeartBeatConfiguration(new Properties())),
-                ImmutableMap.of("CORE.FIXTURE", new ShardingSphereAlgorithmConfiguration("CORE.FIXTURE", new Properties()))));
+                Collections.singletonMap("CORE.FIXTURE", new ShardingSphereAlgorithmConfiguration("CORE.FIXTURE", new Properties()))));
     }
 }
diff --git a/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/query/DatabaseDiscoveryHeartbeatQueryResultSetTest.java b/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/query/DatabaseDiscover [...]
index bab53d7cb44..14853ce2d71 100644
--- a/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/query/DatabaseDiscoveryHeartbeatQueryResultSetTest.java
+++ b/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/query/DatabaseDiscoveryHeartbeatQueryResultSetTest.java
@@ -30,7 +30,6 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Properties;
@@ -64,8 +63,7 @@ public final class DatabaseDiscoveryHeartbeatQueryResultSetTest {
         Properties discoveryTypeProps = new Properties();
         discoveryTypeProps.put("type_key", "type_value");
         DatabaseDiscoveryHeartBeatConfiguration shardingSphereAlgorithmConfig = new DatabaseDiscoveryHeartBeatConfiguration(discoveryTypeProps);
-        Map<String, DatabaseDiscoveryHeartBeatConfiguration> discoverHeartbeat = new HashMap<>(1, 1);
-        discoverHeartbeat.put("test_name", shardingSphereAlgorithmConfig);
+        Map<String, DatabaseDiscoveryHeartBeatConfiguration> discoverHeartbeat = Collections.singletonMap("test_name", shardingSphereAlgorithmConfig);
         return new DatabaseDiscoveryRuleConfiguration(Collections.singleton(databaseDiscoveryDataSourceRuleConfig), discoverHeartbeat, Collections.emptyMap());
     }
 }
diff --git a/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/query/DatabaseDiscoveryProviderAlgorithmQueryResultSetTest.java b/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/query/Database [...]
index f282311c867..e3febd6de79 100644
--- a/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/query/DatabaseDiscoveryProviderAlgorithmQueryResultSetTest.java
+++ b/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/query/DatabaseDiscoveryProviderAlgorithmQueryResultSetTest.java
@@ -30,7 +30,6 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Properties;
@@ -65,8 +64,7 @@ public final class DatabaseDiscoveryProviderAlgorithmQueryResultSetTest {
         Properties discoveryTypeProps = new Properties();
         discoveryTypeProps.put("type_key", "type_value");
         ShardingSphereAlgorithmConfiguration shardingSphereAlgorithmConfig = new ShardingSphereAlgorithmConfiguration("MySQL.MGR", discoveryTypeProps);
-        Map<String, ShardingSphereAlgorithmConfiguration> discoverTypes = new HashMap<>(1, 1);
-        discoverTypes.put("test_name", shardingSphereAlgorithmConfig);
+        Map<String, ShardingSphereAlgorithmConfiguration> discoverTypes = Collections.singletonMap("test_name", shardingSphereAlgorithmConfig);
         return new DatabaseDiscoveryRuleConfiguration(Collections.singleton(databaseDiscoveryDataSourceRuleConfig), Collections.emptyMap(), discoverTypes);
     }
 }
diff --git a/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/query/DatabaseDiscoveryRuleQueryResultSetTest.java b/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/query/DatabaseDiscoveryRule [...]
index 85cb55e3f34..4d065ceccef 100644
--- a/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/query/DatabaseDiscoveryRuleQueryResultSetTest.java
+++ b/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/query/DatabaseDiscoveryRuleQueryResultSetTest.java
@@ -32,7 +32,6 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Properties;
@@ -69,13 +68,11 @@ public final class DatabaseDiscoveryRuleQueryResultSetTest {
     }
     
     private RuleConfiguration createRuleConfiguration() {
-        DatabaseDiscoveryDataSourceRuleConfiguration databaseDiscoveryDataSourceRuleConfig = new DatabaseDiscoveryDataSourceRuleConfiguration("ms_group", Arrays.asList("ds_0", "ds_1"),
-                "heartbeat_test", "type_test");
+        DatabaseDiscoveryDataSourceRuleConfiguration databaseDiscoveryDataSourceRuleConfig = new DatabaseDiscoveryDataSourceRuleConfiguration(
+                "ms_group", Arrays.asList("ds_0", "ds_1"), "heartbeat_test", "type_test");
         ShardingSphereAlgorithmConfiguration shardingSphereAlgorithmConfig = new ShardingSphereAlgorithmConfiguration("MySQL.MGR", new Properties());
-        Map<String, ShardingSphereAlgorithmConfiguration> discoverTypes = new HashMap<>(1, 1);
-        discoverTypes.put("type_test", shardingSphereAlgorithmConfig);
-        Map<String, DatabaseDiscoveryHeartBeatConfiguration> discoveryHeartbeat = new HashMap<>(1, 1);
-        discoveryHeartbeat.put("heartbeat_test", new DatabaseDiscoveryHeartBeatConfiguration(new Properties()));
+        Map<String, DatabaseDiscoveryHeartBeatConfiguration> discoveryHeartbeat = Collections.singletonMap("heartbeat_test", new DatabaseDiscoveryHeartBeatConfiguration(new Properties()));
+        Map<String, ShardingSphereAlgorithmConfiguration> discoverTypes = Collections.singletonMap("type_test", shardingSphereAlgorithmConfig);
         return new DatabaseDiscoveryRuleConfiguration(Collections.singleton(databaseDiscoveryDataSourceRuleConfig), discoveryHeartbeat, discoverTypes);
     }
 }
diff --git a/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/update/DropDatabaseDiscoveryRuleStatementUpdaterTest.java b/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/update/DropDatabaseD [...]
index bf44267763d..fceda1ff093 100644
--- a/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/update/DropDatabaseDiscoveryRuleStatementUpdaterTest.java
+++ b/shardingsphere-features/shardingsphere-db-discovery/shardingsphere-db-discovery-distsql/shardingsphere-db-discovery-distsql-handler/src/test/java/org/apache/shardingsphere/dbdiscovery/distsql/handler/update/DropDatabaseDiscoveryRuleStatementUpdaterTest.java
@@ -30,7 +30,6 @@ import org.junit.Test;
 
 import java.util.Arrays;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.LinkedList;
 import java.util.Map;
 import java.util.Properties;
@@ -99,15 +98,15 @@ public final class DropDatabaseDiscoveryRuleStatementUpdaterTest {
     
     private DatabaseDiscoveryRuleConfiguration createCurrentRuleConfiguration() {
         DatabaseDiscoveryDataSourceRuleConfiguration dataSourceRuleConfig = new DatabaseDiscoveryDataSourceRuleConfiguration("ha_group", Collections.emptyList(), "ha_heartbeat", "readwrite_ds_MGR");
-        Map<String, ShardingSphereAlgorithmConfiguration> discoveryTypes = new HashMap<>(1, 1);
-        discoveryTypes.put("readwrite_ds_MGR", new ShardingSphereAlgorithmConfiguration("readwrite_ds_MGR", new Properties()));
+        Map<String, ShardingSphereAlgorithmConfiguration> discoveryTypes = Collections.singletonMap(
+                "readwrite_ds_MGR", new ShardingSphereAlgorithmConfiguration("readwrite_ds_MGR", new Properties()));
         return new DatabaseDiscoveryRuleConfiguration(new LinkedList<>(Collections.singleton(dataSourceRuleConfig)), Collections.emptyMap(), discoveryTypes);
     }
     
     private DatabaseDiscoveryRuleConfiguration createMultipleCurrentRuleConfigurations() {
         DatabaseDiscoveryDataSourceRuleConfiguration dataSourceRuleConfig = new DatabaseDiscoveryDataSourceRuleConfiguration("ha_group", Collections.emptyList(), "ha_heartbeat", "readwrite_ds_MGR");
-        Map<String, ShardingSphereAlgorithmConfiguration> discoveryTypes = new HashMap<>(1, 1);
-        discoveryTypes.put("readwrite_ds_MGR", new ShardingSphereAlgorithmConfiguration("readwrite_ds_MGR", new Properties()));
+        Map<String, ShardingSphereAlgorithmConfiguration> discoveryTypes = Collections.singletonMap(
+                "readwrite_ds_MGR", new ShardingSphereAlgorithmConfiguration("readwrite_ds_MGR", new Properties()));
         return new DatabaseDiscoveryRuleConfiguration(new LinkedList<>(Arrays.asList(dataSourceRuleConfig,
                 new DatabaseDiscoveryDataSourceRuleConfiguration("ha_group_another", Collections.emptyList(), "ha_heartbeat", "readwrite_ds_MGR"))), Collections.emptyMap(), discoveryTypes);
     }
diff --git a/shardingsphere-features/shardingsphere-encrypt/shardingsphere-encrypt-core/src/test/java/org/apache/shardingsphere/encrypt/rewrite/impl/EncryptOrderByItemTokenGeneratorTest.java b/shardingsphere-features/shardingsphere-encrypt/shardingsphere-encrypt-core/src/test/java/org/apache/shardingsphere/encrypt/rewrite/impl/EncryptOrderByItemTokenGeneratorTest.java
index 7d74615d407..385004e7c3c 100644
--- a/shardingsphere-features/shardingsphere-encrypt/shardingsphere-encrypt-core/src/test/java/org/apache/shardingsphere/encrypt/rewrite/impl/EncryptOrderByItemTokenGeneratorTest.java
+++ b/shardingsphere-features/shardingsphere-encrypt/shardingsphere-encrypt-core/src/test/java/org/apache/shardingsphere/encrypt/rewrite/impl/EncryptOrderByItemTokenGeneratorTest.java
@@ -26,7 +26,6 @@ import org.apache.shardingsphere.infra.binder.segment.table.TablesContext;
 import org.apache.shardingsphere.infra.binder.statement.dml.SelectStatementContext;
 import org.apache.shardingsphere.infra.database.type.DatabaseTypeEngine;
 import org.apache.shardingsphere.infra.metadata.schema.ShardingSphereSchema;
-import org.apache.shardingsphere.infra.rewrite.sql.token.pojo.generic.SubstitutableColumnNameToken;
 import org.apache.shardingsphere.sql.parser.sql.common.constant.OrderDirection;
 import org.apache.shardingsphere.sql.parser.sql.common.segment.dml.column.ColumnSegment;
 import org.apache.shardingsphere.sql.parser.sql.common.segment.dml.order.item.ColumnOrderByItemSegment;
@@ -38,10 +37,7 @@ import org.apache.shardingsphere.sql.parser.sql.common.value.identifier.Identifi
 import org.junit.Before;
 import org.junit.Test;
 
-import java.util.Collection;
 import java.util.Collections;
-import java.util.HashMap;
-import java.util.Map;
 import java.util.Optional;
 
 import static org.hamcrest.CoreMatchers.is;
@@ -58,13 +54,12 @@ public final class EncryptOrderByItemTokenGeneratorTest {
     public void setup() {
         generator = new EncryptOrderByItemTokenGenerator();
         generator.setEncryptRule(buildEncryptRule());
-        generator.setSchemas(mockSchemaMap());
+        generator.setSchemas(Collections.singletonMap("test", mock(ShardingSphereSchema.class)));
     }
     
     @Test
     public void assertGenerateSQLTokens() {
-        Collection<SubstitutableColumnNameToken> sqlTokens = generator.generateSQLTokens(buildSelectStatementContext());
-        assertThat(sqlTokens.size(), is(1));
+        assertThat(generator.generateSQLTokens(buildSelectStatementContext()).size(), is(1));
     }
     
     private SelectStatementContext buildSelectStatementContext() {
@@ -93,10 +88,4 @@ public final class EncryptOrderByItemTokenGeneratorTest {
         when(result.findEncryptTable("t_encrypt")).thenReturn(Optional.of(encryptTable));
         return result;
     }
-    
-    private Map<String, ShardingSphereSchema> mockSchemaMap() {
-        Map<String, ShardingSphereSchema> result = new HashMap<>(1, 1);
-        result.put("test", mock(ShardingSphereSchema.class));
-        return result;
-    }
 }
diff --git a/shardingsphere-features/shardingsphere-encrypt/shardingsphere-encrypt-core/src/test/java/org/apache/shardingsphere/encrypt/rewrite/parameter/EncryptParameterRewriterBuilderTest.java b/shardingsphere-features/shardingsphere-encrypt/shardingsphere-encrypt-core/src/test/java/org/apache/shardingsphere/encrypt/rewrite/parameter/EncryptParameterRewriterBuilderTest.java
index 45730159bae..71ad88f1539 100644
--- a/shardingsphere-features/shardingsphere-encrypt/shardingsphere-encrypt-core/src/test/java/org/apache/shardingsphere/encrypt/rewrite/parameter/EncryptParameterRewriterBuilderTest.java
+++ b/shardingsphere-features/shardingsphere-encrypt/shardingsphere-encrypt-core/src/test/java/org/apache/shardingsphere/encrypt/rewrite/parameter/EncryptParameterRewriterBuilderTest.java
@@ -28,8 +28,6 @@ import org.junit.Test;
 
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashMap;
-import java.util.Map;
 
 import static org.hamcrest.CoreMatchers.instanceOf;
 import static org.hamcrest.CoreMatchers.is;
@@ -50,7 +48,7 @@ public final class EncryptParameterRewriterBuilderTest {
         SQLStatementContext<?> sqlStatementContext = mock(SelectStatementContext.class, RETURNS_DEEP_STUBS);
         when(sqlStatementContext.getTablesContext().getTableNames()).thenReturn(Collections.singletonList("t_order"));
         Collection<ParameterRewriter> actual = new EncryptParameterRewriterBuilder(
-                encryptRule, DefaultDatabase.LOGIC_NAME, mockSchemaMap(), sqlStatementContext, Collections.emptyList()).getParameterRewriters();
+                encryptRule, DefaultDatabase.LOGIC_NAME, Collections.singletonMap("test", mock(ShardingSphereSchema.class)), sqlStatementContext, Collections.emptyList()).getParameterRewriters();
         assertThat(actual.size(), is(1));
         ParameterRewriter parameterRewriter = actual.iterator().next();
         assertThat(parameterRewriter, instanceOf(EncryptPredicateParameterRewriter.class));
@@ -63,12 +61,7 @@ public final class EncryptParameterRewriterBuilderTest {
         SelectStatementContext sqlStatementContext = mock(SelectStatementContext.class, RETURNS_DEEP_STUBS);
         when(sqlStatementContext.getTablesContext().getTableNames()).thenReturn(Collections.singletonList("t_order"));
         when(sqlStatementContext.getWhereSegments()).thenReturn(Collections.emptyList());
-        assertTrue(new EncryptParameterRewriterBuilder(encryptRule, DefaultDatabase.LOGIC_NAME, mockSchemaMap(), sqlStatementContext, Collections.emptyList()).getParameterRewriters().isEmpty());
-    }
-    
-    private Map<String, ShardingSphereSchema> mockSchemaMap() {
-        Map<String, ShardingSphereSchema> result = new HashMap<>(1, 1);
-        result.put("test", mock(ShardingSphereSchema.class));
-        return result;
+        assertTrue(new EncryptParameterRewriterBuilder(encryptRule, 
+                DefaultDatabase.LOGIC_NAME, Collections.singletonMap("test", mock(ShardingSphereSchema.class)), sqlStatementContext, Collections.emptyList()).getParameterRewriters().isEmpty());
     }
 }
diff --git a/shardingsphere-features/shardingsphere-encrypt/shardingsphere-encrypt-distsql/shardingsphere-encrypt-distsql-handler/src/test/java/org/apache/shardingsphere/encrypt/distsql/handler/update/DropEncryptRuleStatementUpdaterTest.java b/shardingsphere-features/shardingsphere-encrypt/shardingsphere-encrypt-distsql/shardingsphere-encrypt-distsql-handler/src/test/java/org/apache/shardingsphere/encrypt/distsql/handler/update/DropEncryptRuleStatementUpdaterTest.java
index 621d8dbb1de..046b9e69fb9 100644
--- a/shardingsphere-features/shardingsphere-encrypt/shardingsphere-encrypt-distsql/shardingsphere-encrypt-distsql-handler/src/test/java/org/apache/shardingsphere/encrypt/distsql/handler/update/DropEncryptRuleStatementUpdaterTest.java
+++ b/shardingsphere-features/shardingsphere-encrypt/shardingsphere-encrypt-distsql/shardingsphere-encrypt-distsql-handler/src/test/java/org/apache/shardingsphere/encrypt/distsql/handler/update/DropEncryptRuleStatementUpdaterTest.java
@@ -92,16 +92,15 @@ public final class DropEncryptRuleStatementUpdaterTest {
     private EncryptRuleConfiguration createCurrentRuleConfiguration() {
         EncryptColumnRuleConfiguration columnRuleConfig = new EncryptColumnRuleConfiguration("user_id", "user_cipher", "", "user_plain", "t_encrypt_user_id_MD5");
         EncryptTableRuleConfiguration tableRuleConfig = new EncryptTableRuleConfiguration("t_encrypt", Collections.singleton(columnRuleConfig), null);
-        Map<String, ShardingSphereAlgorithmConfiguration> encryptors = new HashMap<>(1, 1);
-        encryptors.put("t_encrypt_user_id_MD5", new ShardingSphereAlgorithmConfiguration("TEST", new Properties()));
+        Map<String, ShardingSphereAlgorithmConfiguration> encryptors = new HashMap<>(
+                Collections.singletonMap("t_encrypt_user_id_MD5", new ShardingSphereAlgorithmConfiguration("TEST", new Properties())));
         return new EncryptRuleConfiguration(new LinkedList<>(Collections.singleton(tableRuleConfig)), encryptors, true);
     }
     
     private EncryptRuleConfiguration createCurrentRuleConfigurationWithMultipleTableRules() {
         EncryptColumnRuleConfiguration columnRuleConfig = new EncryptColumnRuleConfiguration("user_id", "user_cipher", "", "user_plain", "t_encrypt_user_id_MD5");
         EncryptTableRuleConfiguration tableRuleConfig = new EncryptTableRuleConfiguration("t_encrypt", Collections.singleton(columnRuleConfig), null);
-        Map<String, ShardingSphereAlgorithmConfiguration> encryptors = new HashMap<>(1, 1);
-        encryptors.put("t_encrypt_user_id_MD5", new ShardingSphereAlgorithmConfiguration("TEST", new Properties()));
+        Map<String, ShardingSphereAlgorithmConfiguration> encryptors = Collections.singletonMap("t_encrypt_user_id_MD5", new ShardingSphereAlgorithmConfiguration("TEST", new Properties()));
         return new EncryptRuleConfiguration(new LinkedList<>(Arrays.asList(tableRuleConfig,
                 new EncryptTableRuleConfiguration("t_encrypt_another", Collections.singleton(columnRuleConfig), null))), encryptors, true);
     }
diff --git a/shardingsphere-features/shardingsphere-readwrite-splitting/shardingsphere-readwrite-splitting-distsql/shardingsphere-readwrite-splitting-distsql-handler/src/test/java/org/apache/shardingsphere/readwritesplitting/distsql/handler/query/ReadwriteSplittingRuleQueryResultSetTest.java b/shardingsphere-features/shardingsphere-readwrite-splitting/shardingsphere-readwrite-splitting-distsql/shardingsphere-readwrite-splitting-distsql-handler/src/test/java/org/apache/shardingsphere/readw [...]
index 51ab3f93358..34aefb3fd87 100644
--- a/shardingsphere-features/shardingsphere-readwrite-splitting/shardingsphere-readwrite-splitting-distsql/shardingsphere-readwrite-splitting-distsql-handler/src/test/java/org/apache/shardingsphere/readwritesplitting/distsql/handler/query/ReadwriteSplittingRuleQueryResultSetTest.java
+++ b/shardingsphere-features/shardingsphere-readwrite-splitting/shardingsphere-readwrite-splitting-distsql/shardingsphere-readwrite-splitting-distsql-handler/src/test/java/org/apache/shardingsphere/readwritesplitting/distsql/handler/query/ReadwriteSplittingRuleQueryResultSetTest.java
@@ -105,7 +105,8 @@ public final class ReadwriteSplittingRuleQueryResultSetTest {
         ExportableRule exportableRule = mock(ExportableRule.class);
         when(exportableRule.containExportableKey(anyCollection())).thenReturn(true);
         when(metaData.getRuleMetaData().findRules(any())).thenReturn(Collections.singletonList(exportableRule));
-        when(exportableRule.export(anyCollection())).thenReturn(createAutoAwareDataSources());
+        when(exportableRule.export(anyCollection())).thenReturn(
+                Collections.singletonMap(ExportableConstants.EXPORTABLE_KEY_AUTO_AWARE_DATA_SOURCE, Collections.singletonMap("readwrite_ds", getAutoAwareDataSources())));
         when(metaData.getRuleMetaData().findRuleConfiguration(any())).thenReturn(Collections.singleton(createRuleConfigurationWithAutoAwareDataSource()));
         ReadwriteSplittingRuleQueryResultSet resultSet = new ReadwriteSplittingRuleQueryResultSet();
         resultSet.init(metaData, mock(ShowReadwriteSplittingRulesStatement.class));
@@ -120,23 +121,10 @@ public final class ReadwriteSplittingRuleQueryResultSetTest {
     private RuleConfiguration createRuleConfigurationWithAutoAwareDataSource() {
         Properties props = new Properties();
         props.setProperty("auto-aware-data-source-name", "rd_rs");
-        ReadwriteSplittingDataSourceRuleConfiguration dataSourceRuleConfig =
-                new ReadwriteSplittingDataSourceRuleConfiguration("readwrite_ds", "Dynamic", props, "");
+        ReadwriteSplittingDataSourceRuleConfiguration dataSourceRuleConfig = new ReadwriteSplittingDataSourceRuleConfiguration("readwrite_ds", "Dynamic", props, "");
         return new ReadwriteSplittingRuleConfiguration(Collections.singleton(dataSourceRuleConfig), null);
     }
     
-    private Map<String, Object> createAutoAwareDataSources() {
-        Map<String, Object> result = new HashMap<>(1, 1);
-        result.put(ExportableConstants.EXPORTABLE_KEY_AUTO_AWARE_DATA_SOURCE, exportAutoAwareDataSourceMap());
-        return result;
-    }
-    
-    private Map<String, Map<String, String>> exportAutoAwareDataSourceMap() {
-        Map<String, Map<String, String>> result = new HashMap<>(1, 1);
-        result.put("readwrite_ds", getAutoAwareDataSources());
-        return result;
-    }
-    
     private Map<String, String> getAutoAwareDataSources() {
         Map<String, String> result = new HashMap<>(2, 1);
         result.put(ExportableConstants.PRIMARY_DATA_SOURCE_NAME, "write_ds");
diff --git a/shardingsphere-features/shardingsphere-readwrite-splitting/shardingsphere-readwrite-splitting-distsql/shardingsphere-readwrite-splitting-distsql-handler/src/test/java/org/apache/shardingsphere/readwritesplitting/distsql/handler/update/DropReadwriteSplittingRuleStatementUpdaterTest.java b/shardingsphere-features/shardingsphere-readwrite-splitting/shardingsphere-readwrite-splitting-distsql/shardingsphere-readwrite-splitting-distsql-handler/src/test/java/org/apache/shardingspher [...]
index 7e84a6174e3..e12a3a78208 100644
--- a/shardingsphere-features/shardingsphere-readwrite-splitting/shardingsphere-readwrite-splitting-distsql/shardingsphere-readwrite-splitting-distsql-handler/src/test/java/org/apache/shardingsphere/readwritesplitting/distsql/handler/update/DropReadwriteSplittingRuleStatementUpdaterTest.java
+++ b/shardingsphere-features/shardingsphere-readwrite-splitting/shardingsphere-readwrite-splitting-distsql/shardingsphere-readwrite-splitting-distsql-handler/src/test/java/org/apache/shardingsphere/readwritesplitting/distsql/handler/update/DropReadwriteSplittingRuleStatementUpdaterTest.java
@@ -34,7 +34,6 @@ import org.mockito.junit.MockitoJUnitRunner;
 
 import java.util.Arrays;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.LinkedList;
 import java.util.Map;
 import java.util.Properties;
@@ -49,11 +48,11 @@ import static org.mockito.Mockito.when;
 @RunWith(MockitoJUnitRunner.class)
 public final class DropReadwriteSplittingRuleStatementUpdaterTest {
     
+    private final DropReadwriteSplittingRuleStatementUpdater updater = new DropReadwriteSplittingRuleStatementUpdater();
+    
     @Mock(answer = Answers.RETURNS_DEEP_STUBS)
     private ShardingSphereMetaData shardingSphereMetaData;
     
-    private final DropReadwriteSplittingRuleStatementUpdater updater = new DropReadwriteSplittingRuleStatementUpdater();
-    
     @Test(expected = RequiredRuleMissedException.class)
     public void assertCheckSQLStatementWithoutCurrentRule() throws RuleDefinitionViolationException {
         updater.checkSQLStatement(shardingSphereMetaData, createSQLStatement(), null);
@@ -98,18 +97,15 @@ public final class DropReadwriteSplittingRuleStatementUpdaterTest {
     }
     
     private ReadwriteSplittingRuleConfiguration createCurrentRuleConfiguration() {
-        Map<String, ShardingSphereAlgorithmConfiguration> loadBalancers = new HashMap<>(1, 1);
-        loadBalancers.put("readwrite_ds", new ShardingSphereAlgorithmConfiguration("TEST", new Properties()));
-        ReadwriteSplittingDataSourceRuleConfiguration dataSourceRuleConfig = new ReadwriteSplittingDataSourceRuleConfiguration("readwrite_ds",
-                "Static", new Properties(), "TEST");
+        ReadwriteSplittingDataSourceRuleConfiguration dataSourceRuleConfig = new ReadwriteSplittingDataSourceRuleConfiguration("readwrite_ds", "Static", new Properties(), "TEST");
+        Map<String, ShardingSphereAlgorithmConfiguration> loadBalancers = Collections.singletonMap("readwrite_ds", new ShardingSphereAlgorithmConfiguration("TEST", new Properties()));
         return new ReadwriteSplittingRuleConfiguration(new LinkedList<>(Collections.singleton(dataSourceRuleConfig)), loadBalancers);
     }
     
     private ReadwriteSplittingRuleConfiguration createMultipleCurrentRuleConfigurations() {
-        Map<String, ShardingSphereAlgorithmConfiguration> loadBalancers = new HashMap<>(1, 1);
-        loadBalancers.put("readwrite_ds", new ShardingSphereAlgorithmConfiguration("TEST", new Properties()));
-        ReadwriteSplittingDataSourceRuleConfiguration dataSourceRuleConfig = new ReadwriteSplittingDataSourceRuleConfiguration("readwrite_ds", "Static", new Properties(), "TEST");
-        return new ReadwriteSplittingRuleConfiguration(new LinkedList<>(Arrays.asList(dataSourceRuleConfig,
-                new ReadwriteSplittingDataSourceRuleConfiguration("readwrite_ds_another", "Static", new Properties(), "TEST"))), loadBalancers);
+        ReadwriteSplittingDataSourceRuleConfiguration fooDataSourceRuleConfig = new ReadwriteSplittingDataSourceRuleConfiguration("foo_ds", "Static", new Properties(), "TEST");
+        ReadwriteSplittingDataSourceRuleConfiguration barDataSourceRuleConfig = new ReadwriteSplittingDataSourceRuleConfiguration("bar_ds", "Static", new Properties(), "TEST");
+        Map<String, ShardingSphereAlgorithmConfiguration> loadBalancers = Collections.singletonMap("foo_ds", new ShardingSphereAlgorithmConfiguration("TEST", new Properties()));
+        return new ReadwriteSplittingRuleConfiguration(new LinkedList<>(Arrays.asList(fooDataSourceRuleConfig, barDataSourceRuleConfig)), loadBalancers);
     }
 }
diff --git a/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-core/src/test/java/org/apache/shardingsphere/sharding/merge/dal/show/ShowCreateTableMergedResultTest.java b/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-core/src/test/java/org/apache/shardingsphere/sharding/merge/dal/show/ShowCreateTableMergedResultTest.java
index 2b2d968aeca..e557d07fcc8 100644
--- a/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-core/src/test/java/org/apache/shardingsphere/sharding/merge/dal/show/ShowCreateTableMergedResultTest.java
+++ b/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-core/src/test/java/org/apache/shardingsphere/sharding/merge/dal/show/ShowCreateTableMergedResultTest.java
@@ -29,10 +29,8 @@ import org.junit.Before;
 import org.junit.Test;
 
 import java.sql.SQLException;
-import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
-import java.util.LinkedList;
 import java.util.Map;
 
 import static org.hamcrest.CoreMatchers.is;
@@ -56,27 +54,20 @@ public final class ShowCreateTableMergedResultTest {
     }
     
     private ShardingRule buildShardingRule() {
-        ShardingTableRuleConfiguration orderTableRuleConfig = new ShardingTableRuleConfiguration("t_order", "ds.t_order_${0..2}");
-        ShardingTableRuleConfiguration userTableRuleConfig = new ShardingTableRuleConfiguration("t_user", "ds.t_user_${0..2}");
         ShardingRuleConfiguration shardingRuleConfig = new ShardingRuleConfiguration();
-        shardingRuleConfig.getTables().add(orderTableRuleConfig);
-        shardingRuleConfig.getTables().add(userTableRuleConfig);
+        shardingRuleConfig.getTables().add(new ShardingTableRuleConfiguration("t_order", "ds.t_order_${0..2}"));
+        shardingRuleConfig.getTables().add(new ShardingTableRuleConfiguration("t_user", "ds.t_user_${0..2}"));
         return new ShardingRule(shardingRuleConfig, Collections.singletonList("ds"));
     }
     
     private ShardingSphereSchema buildSchema() {
-        Map<String, TableMetaData> tableMetaDataMap = new HashMap<>(1, 1);
-        tableMetaDataMap.put("t_order", new TableMetaData("t_order", Collections.emptyList(), Collections.emptyList(), buildConstraintMetaData()));
+        Map<String, TableMetaData> tableMetaDataMap = new HashMap<>(2, 1);
+        tableMetaDataMap.put("t_order",
+                new TableMetaData("t_order", Collections.emptyList(), Collections.emptyList(), Collections.singleton(new ConstraintMetaData("t_order_foreign_key", "t_user"))));
         tableMetaDataMap.put("t_user", new TableMetaData("t_user", Collections.emptyList(), Collections.emptyList(), Collections.emptyList()));
         return new ShardingSphereSchema(tableMetaDataMap);
     }
     
-    private Collection<ConstraintMetaData> buildConstraintMetaData() {
-        Collection<ConstraintMetaData> result = new LinkedList<>();
-        result.add(new ConstraintMetaData("t_order_foreign_key", "t_user"));
-        return result;
-    }
-    
     @Test
     public void assertNextForEmptyQueryResult() throws SQLException {
         assertFalse(new ShowCreateTableMergedResult(shardingRule, mock(SQLStatementContext.class), schema, Collections.emptyList()).next());
diff --git a/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-core/src/test/java/org/apache/shardingsphere/sharding/merge/dal/show/ShowTableStatusMergedResultTest.java b/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-core/src/test/java/org/apache/shardingsphere/sharding/merge/dal/show/ShowTableStatusMergedResultTest.java
index 14feddc8a5a..a2044c259f4 100644
--- a/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-core/src/test/java/org/apache/shardingsphere/sharding/merge/dal/show/ShowTableStatusMergedResultTest.java
+++ b/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-core/src/test/java/org/apache/shardingsphere/sharding/merge/dal/show/ShowTableStatusMergedResultTest.java
@@ -35,8 +35,6 @@ import java.math.BigInteger;
 import java.sql.SQLException;
 import java.sql.Timestamp;
 import java.util.Collections;
-import java.util.HashMap;
-import java.util.Map;
 
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
@@ -56,7 +54,13 @@ public final class ShowTableStatusMergedResultTest {
     @Before
     public void setUp() {
         shardingRule = buildShardingRule();
-        schema = buildSchema();
+        schema = new ShardingSphereSchema(Collections.singletonMap("table", new TableMetaData("table", Collections.emptyList(), Collections.emptyList(), Collections.emptyList())));
+    }
+    
+    private ShardingRule buildShardingRule() {
+        ShardingRuleConfiguration shardingRuleConfig = new ShardingRuleConfiguration();
+        shardingRuleConfig.getTables().add(new ShardingTableRuleConfiguration("table", "ds.table_${0..2}"));
+        return new ShardingRule(shardingRuleConfig, Collections.singletonList("ds"));
     }
     
     @Test
@@ -95,17 +99,4 @@ public final class ShowTableStatusMergedResultTest {
         when(result.getValue(18, Object.class)).thenReturn("");
         return result;
     }
-    
-    private ShardingRule buildShardingRule() {
-        ShardingTableRuleConfiguration tableRuleConfig = new ShardingTableRuleConfiguration("table", "ds.table_${0..2}");
-        ShardingRuleConfiguration shardingRuleConfig = new ShardingRuleConfiguration();
-        shardingRuleConfig.getTables().add(tableRuleConfig);
-        return new ShardingRule(shardingRuleConfig, Collections.singletonList("ds"));
-    }
-    
-    private ShardingSphereSchema buildSchema() {
-        Map<String, TableMetaData> tableMetaDataMap = new HashMap<>(1, 1);
-        tableMetaDataMap.put("table", new TableMetaData("table", Collections.emptyList(), Collections.emptyList(), Collections.emptyList()));
-        return new ShardingSphereSchema(tableMetaDataMap);
-    }
 }
diff --git a/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-core/src/test/java/org/apache/shardingsphere/sharding/merge/dal/show/ShowTablesMergedResultTest.java b/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-core/src/test/java/org/apache/shardingsphere/sharding/merge/dal/show/ShowTablesMergedResultTest.java
index e008474fd9a..4ba47d1d0b5 100644
--- a/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-core/src/test/java/org/apache/shardingsphere/sharding/merge/dal/show/ShowTablesMergedResultTest.java
+++ b/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-core/src/test/java/org/apache/shardingsphere/sharding/merge/dal/show/ShowTablesMergedResultTest.java
@@ -29,8 +29,6 @@ import org.junit.Test;
 
 import java.sql.SQLException;
 import java.util.Collections;
-import java.util.HashMap;
-import java.util.Map;
 
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
@@ -46,21 +44,24 @@ public final class ShowTablesMergedResultTest {
     
     @Before
     public void setUp() {
-        shardingRule = buildShardingRule();
-        schema = buildSchema();
+        shardingRule = createShardingRule();
+        schema = new ShardingSphereSchema(Collections.singletonMap("table", new TableMetaData("table", Collections.emptyList(), Collections.emptyList(), Collections.emptyList())));
     }
     
-    private ShardingRule buildShardingRule() {
-        ShardingTableRuleConfiguration tableRuleConfig = new ShardingTableRuleConfiguration("table", "ds.table_${0..2}");
+    private ShardingRule createShardingRule() {
         ShardingRuleConfiguration shardingRuleConfig = new ShardingRuleConfiguration();
-        shardingRuleConfig.getTables().add(tableRuleConfig);
-        return new ShardingRule(shardingRuleConfig, Collections.singletonList("ds"));
+        shardingRuleConfig.getTables().add(new ShardingTableRuleConfiguration("table", "ds.table_${0..2}"));
+        return new ShardingRule(shardingRuleConfig, Collections.singleton("ds"));
     }
     
-    private ShardingSphereSchema buildSchema() {
-        Map<String, TableMetaData> tableMetaDataMap = new HashMap<>(1, 1);
-        tableMetaDataMap.put("table", new TableMetaData("table", Collections.emptyList(), Collections.emptyList(), Collections.emptyList()));
-        return new ShardingSphereSchema(tableMetaDataMap);
+    @Test
+    public void assertNextForEmptyQueryResult() throws SQLException {
+        assertFalse(new LogicTablesMergedResult(shardingRule, mock(SQLStatementContext.class), schema, Collections.emptyList()).next());
+    }
+    
+    @Test
+    public void assertNextForActualTableNameInTableRule() throws SQLException {
+        assertTrue(new LogicTablesMergedResult(shardingRule, mock(SQLStatementContext.class), schema, Collections.singletonList(mockQueryResult("table_0"))).next());
     }
     
     private QueryResult mockQueryResult(final String value) throws SQLException {
@@ -70,16 +71,4 @@ public final class ShowTablesMergedResultTest {
         when(result.getMetaData().getColumnCount()).thenReturn(1);
         return result;
     }
-    
-    @Test
-    public void assertNextForEmptyQueryResult() throws SQLException {
-        LogicTablesMergedResult actual = new LogicTablesMergedResult(shardingRule, mock(SQLStatementContext.class), schema, Collections.emptyList());
-        assertFalse(actual.next());
-    }
-    
-    @Test
-    public void assertNextForActualTableNameInTableRule() throws SQLException {
-        LogicTablesMergedResult actual = new LogicTablesMergedResult(shardingRule, mock(SQLStatementContext.class), schema, Collections.singletonList(mockQueryResult("table_0")));
-        assertTrue(actual.next());
-    }
 }
diff --git a/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-distsql/shardingsphere-sharding-distsql-handler/src/main/java/org/apache/shardingsphere/scaling/distsql/handler/update/CreateShardingScalingRuleStatementUpdater.java b/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-distsql/shardingsphere-sharding-distsql-handler/src/main/java/org/apache/shardingsphere/scaling/distsql/handler/update/CreateShardingScalingRuleStatementUpdater.java
index 37ad0fa5ac6..a05ed434d5c 100644
--- a/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-distsql/shardingsphere-sharding-distsql-handler/src/main/java/org/apache/shardingsphere/scaling/distsql/handler/update/CreateShardingScalingRuleStatementUpdater.java
+++ b/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-distsql/shardingsphere-sharding-distsql-handler/src/main/java/org/apache/shardingsphere/scaling/distsql/handler/update/CreateShardingScalingRuleStatementUpdater.java
@@ -36,8 +36,6 @@ import org.apache.shardingsphere.sharding.api.config.ShardingRuleConfiguration;
 import org.apache.shardingsphere.spi.exception.ServiceProviderNotFoundException;
 
 import java.util.Collections;
-import java.util.HashMap;
-import java.util.Map;
 import java.util.Properties;
 
 /**
@@ -116,21 +114,12 @@ public final class CreateShardingScalingRuleStatementUpdater implements RuleDefi
     @Override
     public ShardingRuleConfiguration buildToBeCreatedRuleConfiguration(final CreateShardingScalingRuleStatement sqlStatement) {
         ShardingRuleConfiguration result = new ShardingRuleConfiguration();
-        Map<String, OnRuleAlteredActionConfiguration> scalingConfigurationMap = new HashMap<>(1, 1);
-        scalingConfigurationMap.put(sqlStatement.getScalingName(), buildScalingConfiguration(sqlStatement.getScalingRuleConfigSegment()));
-        result.setScaling(scalingConfigurationMap);
+        result.setScaling(Collections.singletonMap(sqlStatement.getScalingName(), buildScalingConfiguration(sqlStatement.getScalingRuleConfigSegment())));
         return result;
     }
     
     private OnRuleAlteredActionConfiguration buildScalingConfiguration(final ShardingScalingRuleConfigurationSegment segment) {
-        if (null == segment) {
-            return buildNullScalingConfiguration();
-        }
-        return ShardingScalingRuleStatementConverter.convert(segment);
-    }
-    
-    private OnRuleAlteredActionConfiguration buildNullScalingConfiguration() {
-        return null;
+        return null == segment ? null : ShardingScalingRuleStatementConverter.convert(segment);
     }
     
     @Override
diff --git a/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-distsql/shardingsphere-sharding-distsql-handler/src/test/java/org/apache/shardingsphere/scaling/distsql/handler/query/ShardingScalingRulesQueryResultSetTest.java b/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-distsql/shardingsphere-sharding-distsql-handler/src/test/java/org/apache/shardingsphere/scaling/distsql/handler/query/ShardingScalingRulesQueryResultSetTest.java
index 64e71059592..60f9ad0c5ee 100644
--- a/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-distsql/shardingsphere-sharding-distsql-handler/src/test/java/org/apache/shardingsphere/scaling/distsql/handler/query/ShardingScalingRulesQueryResultSetTest.java
+++ b/shardingsphere-features/shardingsphere-sharding/shardingsphere-sharding-distsql/shardingsphere-sharding-distsql-handler/src/test/java/org/apache/shardingsphere/scaling/distsql/handler/query/ShardingScalingRulesQueryResultSetTest.java
@@ -29,9 +29,7 @@ import org.junit.Test;
 
 import java.util.ArrayList;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.List;
-import java.util.Map;
 import java.util.Properties;
 
 import static org.hamcrest.CoreMatchers.containsString;
@@ -64,32 +62,26 @@ public final class ShardingScalingRulesQueryResultSetTest {
     }
     
     private RuleConfiguration createRuleConfiguration() {
-        Map<String, OnRuleAlteredActionConfiguration> scalingRuleConfigurationMap = new HashMap<>(1, 1);
-        scalingRuleConfigurationMap.put("scaling_name", buildCompleteConfiguration());
         ShardingRuleConfiguration result = new ShardingRuleConfiguration();
-        result.setScaling(scalingRuleConfigurationMap);
+        result.setScaling(Collections.singletonMap("scaling_name", buildCompleteConfiguration()));
         return result;
     }
     
     private OnRuleAlteredActionConfiguration buildCompleteConfiguration() {
         InputConfiguration inputConfig = createInputConfiguration("QPS", newProperties("qps", "50"));
         OutputConfiguration outputConfig = createOutputConfiguration("TPS", newProperties("tps", "2000"));
-        ShardingSphereAlgorithmConfiguration streamChannel = createAlgorithm("MEMORY", newProperties("block-queue-size", "10000"));
-        ShardingSphereAlgorithmConfiguration completionDetector = createAlgorithm("IDLE", newProperties("incremental-task-idle-seconds-threshold", "1800"));
-        ShardingSphereAlgorithmConfiguration dataConsistencyChecker = createAlgorithm("DATA_MATCH", newProperties("chunk-size", "1000"));
+        ShardingSphereAlgorithmConfiguration streamChannel = new ShardingSphereAlgorithmConfiguration("MEMORY", newProperties("block-queue-size", "10000"));
+        ShardingSphereAlgorithmConfiguration completionDetector = new ShardingSphereAlgorithmConfiguration("IDLE", newProperties("incremental-task-idle-seconds-threshold", "1800"));
+        ShardingSphereAlgorithmConfiguration dataConsistencyChecker = new ShardingSphereAlgorithmConfiguration("DATA_MATCH", newProperties("chunk-size", "1000"));
         return new OnRuleAlteredActionConfiguration(inputConfig, outputConfig, streamChannel, completionDetector, dataConsistencyChecker);
     }
     
     private InputConfiguration createInputConfiguration(final String type, final Properties props) {
-        return new InputConfiguration(10, 100, 10, createAlgorithm(type, props));
+        return new InputConfiguration(10, 100, 10, new ShardingSphereAlgorithmConfiguration(type, props));
     }
     
     private OutputConfiguration createOutputConfiguration(final String type, final Properties props) {
-        return new OutputConfiguration(10, 100, createAlgorithm(type, props));
-    }
-    
-    private ShardingSphereAlgorithmConfiguration createAlgorithm(final String type, final Properties props) {
-        return new ShardingSphereAlgorithmConfiguration(type, props);
+        return new OutputConfiguration(10, 100, new ShardingSphereAlgorithmConfiguration(type, props));
     }
     
     private Properties newProperties(final String key, final String value) {
diff --git a/shardingsphere-infra/shardingsphere-infra-binder/src/test/java/org/apache/shardingsphere/infra/binder/segment/insert/keygen/engine/GeneratedKeyContextEngineTest.java b/shardingsphere-infra/shardingsphere-infra-binder/src/test/java/org/apache/shardingsphere/infra/binder/segment/insert/keygen/engine/GeneratedKeyContextEngineTest.java
index 820645e303f..88ead2d06ec 100644
--- a/shardingsphere-infra/shardingsphere-infra-binder/src/test/java/org/apache/shardingsphere/infra/binder/segment/insert/keygen/engine/GeneratedKeyContextEngineTest.java
+++ b/shardingsphere-infra/shardingsphere-infra-binder/src/test/java/org/apache/shardingsphere/infra/binder/segment/insert/keygen/engine/GeneratedKeyContextEngineTest.java
@@ -44,10 +44,8 @@ import org.mockito.junit.MockitoJUnitRunner;
 
 import java.sql.Types;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.Iterator;
 import java.util.List;
-import java.util.Map;
 import java.util.Optional;
 import java.util.stream.Collectors;
 
@@ -63,10 +61,9 @@ public final class GeneratedKeyContextEngineTest {
     
     @Before
     public void setUp() {
-        TableMetaData tableMetaData = new TableMetaData("tbl", Collections.singletonList(new ColumnMetaData("id", Types.INTEGER, true, true, false)), Collections.emptyList(), Collections.emptyList());
-        Map<String, TableMetaData> tableMetaDataMap = new HashMap<>(1, 1);
-        tableMetaDataMap.put("tbl", tableMetaData);
-        schema = new ShardingSphereSchema(tableMetaDataMap);
+        TableMetaData tableMetaData = new TableMetaData(
+                "tbl", Collections.singletonList(new ColumnMetaData("id", Types.INTEGER, true, true, false)), Collections.emptyList(), Collections.emptyList());
+        schema = new ShardingSphereSchema(Collections.singletonMap("tbl", tableMetaData));
     }
     
     @Test
diff --git a/shardingsphere-infra/shardingsphere-infra-common/src/main/java/org/apache/shardingsphere/infra/yaml/config/pojo/rulealtered/YamlOnRuleAlteredActionConfiguration.java b/shardingsphere-infra/shardingsphere-infra-common/src/main/java/org/apache/shardingsphere/infra/yaml/config/pojo/rulealtered/YamlOnRuleAlteredActionConfiguration.java
index 5a1caa7dbef..80f510f2dac 100644
--- a/shardingsphere-infra/shardingsphere-infra-common/src/main/java/org/apache/shardingsphere/infra/yaml/config/pojo/rulealtered/YamlOnRuleAlteredActionConfiguration.java
+++ b/shardingsphere-infra/shardingsphere-infra-common/src/main/java/org/apache/shardingsphere/infra/yaml/config/pojo/rulealtered/YamlOnRuleAlteredActionConfiguration.java
@@ -105,7 +105,7 @@ public final class YamlOnRuleAlteredActionConfiguration implements YamlConfigura
         public static YamlOutputConfiguration buildWithDefaultValue() {
             return new YamlOutputConfiguration();
         }
-    
+        
         /**
          * Fill in null fields with default value.
          */
diff --git a/shardingsphere-infra/shardingsphere-infra-common/src/test/java/org/apache/shardingsphere/infra/datasource/pool/creator/DataSourcePoolCreatorTest.java b/shardingsphere-infra/shardingsphere-infra-common/src/test/java/org/apache/shardingsphere/infra/datasource/pool/creator/DataSourcePoolCreatorTest.java
index 6f8ff695071..62f1587a655 100644
--- a/shardingsphere-infra/shardingsphere-infra-common/src/test/java/org/apache/shardingsphere/infra/datasource/pool/creator/DataSourcePoolCreatorTest.java
+++ b/shardingsphere-infra/shardingsphere-infra-common/src/test/java/org/apache/shardingsphere/infra/datasource/pool/creator/DataSourcePoolCreatorTest.java
@@ -22,7 +22,7 @@ import org.apache.shardingsphere.test.mock.MockedDataSource;
 import org.junit.Test;
 
 import javax.sql.DataSource;
-import java.util.HashMap;
+import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.Map;
 
@@ -34,17 +34,14 @@ public final class DataSourcePoolCreatorTest {
     
     @Test
     public void assertCreateMap() {
-        Map<String, DataSourceProperties> dataSourcePropsMap = new HashMap<>(1, 1);
-        dataSourcePropsMap.put("foo_ds", new DataSourceProperties(MockedDataSource.class.getName(), createProperties()));
-        Map<String, DataSource> actual = DataSourcePoolCreator.create(dataSourcePropsMap);
+        Map<String, DataSource> actual = DataSourcePoolCreator.create(Collections.singletonMap("foo_ds", new DataSourceProperties(MockedDataSource.class.getName(), createProperties())));
         assertThat(actual.size(), is(1));
         assertDataSource((MockedDataSource) actual.get("foo_ds"));
     }
     
     @Test
     public void assertCreate() {
-        MockedDataSource actual = (MockedDataSource) DataSourcePoolCreator.create(new DataSourceProperties(MockedDataSource.class.getName(), createProperties()));
-        assertDataSource(actual);
+        assertDataSource((MockedDataSource) DataSourcePoolCreator.create(new DataSourceProperties(MockedDataSource.class.getName(), createProperties())));
     }
     
     private Map<String, Object> createProperties() {
diff --git a/shardingsphere-infra/shardingsphere-infra-common/src/test/java/org/apache/shardingsphere/infra/datasource/pool/metadata/fixture/MockedDataSourcePoolMetaData.java b/shardingsphere-infra/shardingsphere-infra-common/src/test/java/org/apache/shardingsphere/infra/datasource/pool/metadata/fixture/MockedDataSourcePoolMetaData.java
index 5f6b2b7f575..cd53a7bf19a 100644
--- a/shardingsphere-infra/shardingsphere-infra-common/src/test/java/org/apache/shardingsphere/infra/datasource/pool/metadata/fixture/MockedDataSourcePoolMetaData.java
+++ b/shardingsphere-infra/shardingsphere-infra-common/src/test/java/org/apache/shardingsphere/infra/datasource/pool/metadata/fixture/MockedDataSourcePoolMetaData.java
@@ -28,9 +28,7 @@ public final class MockedDataSourcePoolMetaData implements DataSourcePoolMetaDat
     
     @Override
     public Map<String, Object> getDefaultProperties() {
-        Map<String, Object> result = new HashMap<>(1, 1);
-        result.put("maxPoolSize", 100);
-        return result;
+        return Collections.singletonMap("maxPoolSize", 100);
     }
     
     @Override
diff --git a/shardingsphere-infra/shardingsphere-infra-common/src/test/java/org/apache/shardingsphere/infra/metadata/schema/util/IndexMetaDataUtilTest.java b/shardingsphere-infra/shardingsphere-infra-common/src/test/java/org/apache/shardingsphere/infra/metadata/schema/util/IndexMetaDataUtilTest.java
index a92fa884c9f..cc8cf952eea 100644
--- a/shardingsphere-infra/shardingsphere-infra-common/src/test/java/org/apache/shardingsphere/infra/metadata/schema/util/IndexMetaDataUtilTest.java
+++ b/shardingsphere-infra/shardingsphere-infra-common/src/test/java/org/apache/shardingsphere/infra/metadata/schema/util/IndexMetaDataUtilTest.java
@@ -37,7 +37,6 @@ import org.junit.Test;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.Map;
 
 import static org.hamcrest.CoreMatchers.is;
@@ -93,8 +92,7 @@ public final class IndexMetaDataUtilTest {
     
     private ShardingSphereMetaData buildMetaData() {
         TableMetaData tableMetaData = new TableMetaData(TABLE_NAME, Collections.emptyList(), Collections.singletonList(new IndexMetaData(INDEX_NAME)), Collections.emptyList());
-        Map<String, TableMetaData> tables = new HashMap<>(1, 1);
-        tables.put(TABLE_NAME, tableMetaData);
+        Map<String, TableMetaData> tables = Collections.singletonMap(TABLE_NAME, tableMetaData);
         Map<String, ShardingSphereSchema> schemas = Collections.singletonMap(DefaultDatabase.LOGIC_NAME, new ShardingSphereSchema(tables));
         return new ShardingSphereMetaData(DefaultDatabase.LOGIC_NAME, mock(DatabaseType.class), mock(ShardingSphereResource.class), mock(ShardingSphereRuleMetaData.class), schemas);
     }
diff --git a/shardingsphere-infra/shardingsphere-infra-rewrite/src/test/java/org/apache/shardingsphere/infra/rewrite/context/SQLRewriteContextTest.java b/shardingsphere-infra/shardingsphere-infra-rewrite/src/test/java/org/apache/shardingsphere/infra/rewrite/context/SQLRewriteContextTest.java
index 8089f7e02b5..99e7e75768d 100644
--- a/shardingsphere-infra/shardingsphere-infra-rewrite/src/test/java/org/apache/shardingsphere/infra/rewrite/context/SQLRewriteContextTest.java
+++ b/shardingsphere-infra/shardingsphere-infra-rewrite/src/test/java/org/apache/shardingsphere/infra/rewrite/context/SQLRewriteContextTest.java
@@ -35,8 +35,6 @@ import org.mockito.Mock;
 import org.mockito.junit.MockitoJUnitRunner;
 
 import java.util.Collections;
-import java.util.HashMap;
-import java.util.Map;
 
 import static org.hamcrest.CoreMatchers.instanceOf;
 import static org.junit.Assert.assertFalse;
@@ -49,7 +47,7 @@ import static org.mockito.Mockito.when;
 public final class SQLRewriteContextTest {
     
     @Mock
-    private SQLStatementContext sqlStatementContext;
+    private SQLStatementContext<?> sqlStatementContext;
     
     @Mock
     private SQLToken sqlToken;
@@ -60,6 +58,7 @@ public final class SQLRewriteContextTest {
     @Mock
     private CollectionSQLTokenGenerator collectionSQLTokenGenerator;
     
+    @SuppressWarnings("unchecked")
     @Before
     public void setUp() {
         when(optionalSQLTokenGenerator.generateSQLToken(sqlStatementContext)).thenReturn(sqlToken);
@@ -72,7 +71,7 @@ public final class SQLRewriteContextTest {
         when(((TableAvailable) statementContext).getTablesContext().getDatabaseName().isPresent()).thenReturn(false);
         when(statementContext.getInsertSelectContext()).thenReturn(null);
         SQLRewriteContext sqlRewriteContext = new SQLRewriteContext(DefaultDatabase.LOGIC_NAME,
-                mockSchemaMap(), statementContext, "INSERT INTO tbl VALUES (?)", Collections.singletonList(1));
+                Collections.singletonMap("test", mock(ShardingSphereSchema.class)), statementContext, "INSERT INTO tbl VALUES (?)", Collections.singletonList(1));
         assertThat(sqlRewriteContext.getParameterBuilder(), instanceOf(GroupedParameterBuilder.class));
     }
     
@@ -81,14 +80,14 @@ public final class SQLRewriteContextTest {
         SelectStatementContext statementContext = mock(SelectStatementContext.class, RETURNS_DEEP_STUBS);
         when(((TableAvailable) statementContext).getTablesContext().getDatabaseName().isPresent()).thenReturn(false);
         SQLRewriteContext sqlRewriteContext = new SQLRewriteContext(DefaultDatabase.LOGIC_NAME,
-                mockSchemaMap(), statementContext, "SELECT * FROM tbl WHERE id = ?", Collections.singletonList(1));
+                Collections.singletonMap("test", mock(ShardingSphereSchema.class)), statementContext, "SELECT * FROM tbl WHERE id = ?", Collections.singletonList(1));
         assertThat(sqlRewriteContext.getParameterBuilder(), instanceOf(StandardParameterBuilder.class));
     }
     
     @Test
     public void assertGenerateOptionalSQLToken() {
         SQLRewriteContext sqlRewriteContext = new SQLRewriteContext(DefaultDatabase.LOGIC_NAME,
-                mockSchemaMap(), sqlStatementContext, "INSERT INTO tbl VALUES (?)", Collections.singletonList(1));
+                Collections.singletonMap("test", mock(ShardingSphereSchema.class)), sqlStatementContext, "INSERT INTO tbl VALUES (?)", Collections.singletonList(1));
         sqlRewriteContext.addSQLTokenGenerators(Collections.singleton(optionalSQLTokenGenerator));
         sqlRewriteContext.generateSQLTokens();
         assertFalse(sqlRewriteContext.getSqlTokens().isEmpty());
@@ -98,16 +97,10 @@ public final class SQLRewriteContextTest {
     @Test
     public void assertGenerateCollectionSQLToken() {
         SQLRewriteContext sqlRewriteContext = new SQLRewriteContext(DefaultDatabase.LOGIC_NAME,
-                mockSchemaMap(), sqlStatementContext, "INSERT INTO tbl VALUES (?)", Collections.singletonList(1));
+                Collections.singletonMap("test", mock(ShardingSphereSchema.class)), sqlStatementContext, "INSERT INTO tbl VALUES (?)", Collections.singletonList(1));
         sqlRewriteContext.addSQLTokenGenerators(Collections.singleton(collectionSQLTokenGenerator));
         sqlRewriteContext.generateSQLTokens();
         assertFalse(sqlRewriteContext.getSqlTokens().isEmpty());
         assertThat(sqlRewriteContext.getSqlTokens().get(0), instanceOf(SQLToken.class));
     }
-    
-    private Map<String, ShardingSphereSchema> mockSchemaMap() {
-        Map<String, ShardingSphereSchema> result = new HashMap<>(1, 1);
-        result.put("test", mock(ShardingSphereSchema.class));
-        return result;
-    }
 }
diff --git a/shardingsphere-infra/shardingsphere-infra-rewrite/src/test/java/org/apache/shardingsphere/infra/rewrite/sql/token/generator/SQLTokenGeneratorsTest.java b/shardingsphere-infra/shardingsphere-infra-rewrite/src/test/java/org/apache/shardingsphere/infra/rewrite/sql/token/generator/SQLTokenGeneratorsTest.java
index e72c29e133c..0854b9ffb4c 100644
--- a/shardingsphere-infra/shardingsphere-infra-rewrite/src/test/java/org/apache/shardingsphere/infra/rewrite/sql/token/generator/SQLTokenGeneratorsTest.java
+++ b/shardingsphere-infra/shardingsphere-infra-rewrite/src/test/java/org/apache/shardingsphere/infra/rewrite/sql/token/generator/SQLTokenGeneratorsTest.java
@@ -29,7 +29,6 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.Map;
 
 import static org.hamcrest.CoreMatchers.is;
@@ -77,7 +76,8 @@ public final class SQLTokenGeneratorsTest {
         sqlTokenGenerators.addAll(Collections.singleton(optionalSQLTokenGenerator));
         SQLToken expectedToken = mock(SQLToken.class);
         when(optionalSQLTokenGenerator.generateSQLToken(any(SQLStatementContext.class))).thenReturn(expectedToken);
-        Collection<SQLToken> actualSqlTokens = sqlTokenGenerators.generateSQLTokens("sharding_db", mockSchemaMap(), mock(SQLStatementContext.class), Collections.emptyList());
+        Collection<SQLToken> actualSqlTokens = sqlTokenGenerators.generateSQLTokens(
+                "sharding_db", Collections.singletonMap("test", mock(ShardingSphereSchema.class)), mock(SQLStatementContext.class), Collections.emptyList());
         assertThat(actualSqlTokens.size(), is(1));
         assertThat(actualSqlTokens.iterator().next(), is(expectedToken));
     }
@@ -90,7 +90,8 @@ public final class SQLTokenGeneratorsTest {
         sqlTokenGenerators.addAll(Collections.singleton(collectionSQLTokenGenerator));
         Collection<SQLToken> expectedSQLTokens = Arrays.asList(mock(SQLToken.class), mock(SQLToken.class));
         doReturn(expectedSQLTokens).when(collectionSQLTokenGenerator).generateSQLTokens(any());
-        Collection<SQLToken> actualSQLTokens = sqlTokenGenerators.generateSQLTokens("sharding_db", mockSchemaMap(), mock(SQLStatementContext.class), Collections.emptyList());
+        Collection<SQLToken> actualSQLTokens = sqlTokenGenerators.generateSQLTokens(
+                "sharding_db", Collections.singletonMap("test", mock(ShardingSphereSchema.class)), mock(SQLStatementContext.class), Collections.emptyList());
         assertThat(actualSQLTokens.size(), is(2));
         assertThat(actualSQLTokens, is(expectedSQLTokens));
     }
@@ -101,10 +102,4 @@ public final class SQLTokenGeneratorsTest {
         field.setAccessible(true);
         return (Map<Class<?>, SQLTokenGenerator>) field.get(sqlTokenGenerators);
     }
-    
-    private Map<String, ShardingSphereSchema> mockSchemaMap() {
-        Map<String, ShardingSphereSchema> result = new HashMap<>(1, 1);
-        result.put("test", mock(ShardingSphereSchema.class));
-        return result;
-    }
 }
diff --git a/shardingsphere-jdbc/shardingsphere-jdbc-core/src/main/java/org/apache/shardingsphere/driver/api/yaml/YamlShardingSphereDataSourceFactory.java b/shardingsphere-jdbc/shardingsphere-jdbc-core/src/main/java/org/apache/shardingsphere/driver/api/yaml/YamlShardingSphereDataSourceFactory.java
index 4720eb36975..70f42844527 100644
--- a/shardingsphere-jdbc/shardingsphere-jdbc-core/src/main/java/org/apache/shardingsphere/driver/api/yaml/YamlShardingSphereDataSourceFactory.java
+++ b/shardingsphere-jdbc/shardingsphere-jdbc-core/src/main/java/org/apache/shardingsphere/driver/api/yaml/YamlShardingSphereDataSourceFactory.java
@@ -35,7 +35,8 @@ import java.io.File;
 import java.io.IOException;
 import java.sql.SQLException;
 import java.util.Collection;
-import java.util.HashMap;
+import java.util.Collections;
+import java.util.LinkedHashMap;
 import java.util.Map;
 
 /**
@@ -133,8 +134,8 @@ public final class YamlShardingSphereDataSourceFactory {
     }
     
     private static DataSource createDataSource(final DataSource dataSource, final YamlRootConfiguration rootConfig) throws SQLException {
-        Map<String, DataSource> dataSourceMap = new HashMap<>(1, 1);
-        dataSourceMap.put(Strings.isNullOrEmpty(rootConfig.getDatabaseName()) ? DefaultDatabase.LOGIC_NAME : rootConfig.getDatabaseName(), dataSource);
+        Map<String, DataSource> dataSourceMap = new LinkedHashMap<>(
+                Collections.singletonMap(Strings.isNullOrEmpty(rootConfig.getDatabaseName()) ? DefaultDatabase.LOGIC_NAME : rootConfig.getDatabaseName(), dataSource));
         return createDataSource(dataSourceMap, rootConfig);
     }
 }
diff --git a/shardingsphere-jdbc/shardingsphere-jdbc-core/src/test/java/org/apache/shardingsphere/driver/jdbc/core/datasource/metadata/ShardingSphereDatabaseMetaDataTest.java b/shardingsphere-jdbc/shardingsphere-jdbc-core/src/test/java/org/apache/shardingsphere/driver/jdbc/core/datasource/metadata/ShardingSphereDatabaseMetaDataTest.java
index d7ca624ab6d..9c3986bde23 100644
--- a/shardingsphere-jdbc/shardingsphere-jdbc-core/src/test/java/org/apache/shardingsphere/driver/jdbc/core/datasource/metadata/ShardingSphereDatabaseMetaDataTest.java
+++ b/shardingsphere-jdbc/shardingsphere-jdbc-core/src/test/java/org/apache/shardingsphere/driver/jdbc/core/datasource/metadata/ShardingSphereDatabaseMetaDataTest.java
@@ -77,7 +77,7 @@ public final class ShardingSphereDatabaseMetaDataTest {
     @Mock
     private MetaDataContexts metaDataContexts;
     
-    private final Map<String, DataSource> dataSourceMap = new HashMap<>(1, 1);
+    private final Map<String, DataSource> dataSourceMap = new HashMap<>();
     
     private ShardingSphereDatabaseMetaData shardingSphereDatabaseMetaData;
     
diff --git a/shardingsphere-kernel/shardingsphere-single-table/shardingsphere-single-table-core/src/main/java/org/apache/shardingsphere/singletable/rule/SingleTableRule.java b/shardingsphere-kernel/shardingsphere-single-table/shardingsphere-single-table-core/src/main/java/org/apache/shardingsphere/singletable/rule/SingleTableRule.java
index 347d1bb8da2..4227e34a0bb 100644
--- a/shardingsphere-kernel/shardingsphere-single-table/shardingsphere-single-table-core/src/main/java/org/apache/shardingsphere/singletable/rule/SingleTableRule.java
+++ b/shardingsphere-kernel/shardingsphere-single-table/shardingsphere-single-table-core/src/main/java/org/apache/shardingsphere/singletable/rule/SingleTableRule.java
@@ -38,7 +38,6 @@ import org.apache.shardingsphere.singletable.datanode.SingleTableDataNodeLoader;
 import javax.sql.DataSource;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.HashSet;
 import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
@@ -270,8 +269,6 @@ public final class SingleTableRule implements SchemaRule, DataNodeContainedRule,
     
     @Override
     public Map<String, Supplier<Object>> getExportedMethods() {
-        Map<String, Supplier<Object>> result = new HashMap<>(1, 1);
-        result.put(ExportableConstants.EXPORTABLE_KEY_SINGLE_TABLES, tableNames::keySet);
-        return result;
+        return Collections.singletonMap(ExportableConstants.EXPORTABLE_KEY_SINGLE_TABLES, tableNames::keySet);
     }
 }
diff --git a/shardingsphere-kernel/shardingsphere-traffic/shardingsphere-traffic-core/src/test/java/org/apache/shardingsphere/traffic/rule/TrafficRuleTest.java b/shardingsphere-kernel/shardingsphere-traffic/shardingsphere-traffic-core/src/test/java/org/apache/shardingsphere/traffic/rule/TrafficRuleTest.java
index 81bff3ad1af..56f4a8ff1fe 100644
--- a/shardingsphere-kernel/shardingsphere-traffic/shardingsphere-traffic-core/src/test/java/org/apache/shardingsphere/traffic/rule/TrafficRuleTest.java
+++ b/shardingsphere-kernel/shardingsphere-traffic/shardingsphere-traffic-core/src/test/java/org/apache/shardingsphere/traffic/rule/TrafficRuleTest.java
@@ -17,7 +17,6 @@
 
 package org.apache.shardingsphere.traffic.rule;
 
-import com.google.common.collect.Sets;
 import org.apache.shardingsphere.infra.binder.LogicSQL;
 import org.apache.shardingsphere.infra.binder.statement.SQLStatementContext;
 import org.apache.shardingsphere.infra.binder.statement.dml.SelectStatementContext;
@@ -34,10 +33,8 @@ import org.apache.shardingsphere.traffic.api.config.TrafficStrategyConfiguration
 import org.junit.Test;
 
 import java.util.Arrays;
-import java.util.Collection;
 import java.util.Collections;
-import java.util.HashMap;
-import java.util.Map;
+import java.util.HashSet;
 import java.util.Optional;
 import java.util.Properties;
 
@@ -57,16 +54,14 @@ public final class TrafficRuleTest {
         Optional<TrafficStrategyRule> actual = trafficRule.findMatchedStrategyRule(createLogicSQL(true), false);
         assertTrue(actual.isPresent());
         assertThat(actual.get().getName(), is("sql_hint_traffic"));
-        assertThat(actual.get().getLabels(), is(Sets.newHashSet("OLTP", "OLAP")));
+        assertThat(actual.get().getLabels(), is(new HashSet<>(Arrays.asList("OLTP", "OLAP"))));
         assertThat(actual.get().getTrafficAlgorithm(), instanceOf(SQLHintTrafficAlgorithm.class));
         assertThat(actual.get().getLoadBalancer(), instanceOf(RandomTrafficLoadBalanceAlgorithm.class));
     }
     
     @Test
     public void assertFindMatchedStrategyRuleWhenSQLHintNotMatch() {
-        TrafficRule trafficRule = new TrafficRule(createTrafficRuleConfig());
-        Optional<TrafficStrategyRule> actual = trafficRule.findMatchedStrategyRule(createLogicSQL(false), false);
-        assertFalse(actual.isPresent());
+        assertFalse(new TrafficRule(createTrafficRuleConfig()).findMatchedStrategyRule(createLogicSQL(false), false).isPresent());
     }
     
     @Test
@@ -75,37 +70,28 @@ public final class TrafficRuleTest {
         Optional<TrafficStrategyRule> actual = trafficRule.findMatchedStrategyRule(createLogicSQL(false), true);
         assertTrue(actual.isPresent());
         assertThat(actual.get().getName(), is("transaction_traffic"));
-        assertThat(actual.get().getLabels(), is(Sets.newHashSet("OLAP")));
+        assertThat(actual.get().getLabels(), is(Collections.singleton("OLAP")));
         assertThat(actual.get().getTrafficAlgorithm(), instanceOf(ProxyTrafficAlgorithm.class));
         assertThat(actual.get().getLoadBalancer(), instanceOf(RandomTrafficLoadBalanceAlgorithm.class));
     }
     
     @Test
     public void assertGetLabels() {
-        TrafficRule trafficRule = new TrafficRule(createTrafficRuleConfig());
-        Collection<String> actual = trafficRule.getLabels();
-        assertThat(actual, is(Sets.newHashSet("OLAP", "OLTP")));
+        assertThat(new TrafficRule(createTrafficRuleConfig()).getLabels(), is(new HashSet<>(Arrays.asList("OLAP", "OLTP"))));
     }
     
     @SuppressWarnings({"rawtypes", "unchecked"})
     private LogicSQL createLogicSQL(final boolean includeComments) {
         LogicSQL result = mock(LogicSQL.class);
         MySQLSelectStatement sqlStatement = mock(MySQLSelectStatement.class);
-        Collection<CommentSegment> comments = includeComments ? Collections.singletonList(
-                new CommentSegment("/* ShardingSphere hint: useTraffic=true */", 0, 0)) : Collections.emptyList();
-        when(sqlStatement.getCommentSegments()).thenReturn(comments);
+        when(sqlStatement.getCommentSegments()).thenReturn(includeComments ? Collections.singleton(new CommentSegment("/* ShardingSphere hint: useTraffic=true */", 0, 0)) : Collections.emptyList());
         when(sqlStatement.getProjections()).thenReturn(new ProjectionsSegment(0, 0));
-        SQLStatementContext statementContext = new SelectStatementContext(createMetaDataMap(), Collections.emptyList(), sqlStatement, "sharding_db");
+        SQLStatementContext statementContext = new SelectStatementContext(
+                Collections.singletonMap("sharding_db", mock(ShardingSphereMetaData.class)), Collections.emptyList(), sqlStatement, "sharding_db");
         when(result.getSqlStatementContext()).thenReturn(statementContext);
         return result;
     }
     
-    private Map<String, ShardingSphereMetaData> createMetaDataMap() {
-        Map<String, ShardingSphereMetaData> result = new HashMap<>(1, 1);
-        result.put("sharding_db", mock(ShardingSphereMetaData.class));
-        return result;
-    }
-    
     private TrafficRuleConfiguration createTrafficRuleConfig() {
         TrafficRuleConfiguration result = new TrafficRuleConfiguration();
         result.getTrafficStrategies().add(new TrafficStrategyConfiguration("sql_hint_traffic", Arrays.asList("OLTP", "OLAP"), "sql_hint_match", "random"));
diff --git a/shardingsphere-proxy/shardingsphere-proxy-backend/src/test/java/org/apache/shardingsphere/proxy/backend/text/distsql/ral/common/queryable/ExportDatabaseConfigurationHandlerTest.java b/shardingsphere-proxy/shardingsphere-proxy-backend/src/test/java/org/apache/shardingsphere/proxy/backend/text/distsql/ral/common/queryable/ExportDatabaseConfigurationHandlerTest.java
index 7d347fc5ab1..6970c27dc22 100644
--- a/shardingsphere-proxy/shardingsphere-proxy-backend/src/test/java/org/apache/shardingsphere/proxy/backend/text/distsql/ral/common/queryable/ExportDatabaseConfigurationHandlerTest.java
+++ b/shardingsphere-proxy/shardingsphere-proxy-backend/src/test/java/org/apache/shardingsphere/proxy/backend/text/distsql/ral/common/queryable/ExportDatabaseConfigurationHandlerTest.java
@@ -44,7 +44,6 @@ import javax.sql.DataSource;
 import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
@@ -72,7 +71,7 @@ public final class ExportDatabaseConfigurationHandlerTest {
     
     @Test
     public void assertExportDatabaseExecutor() throws SQLException {
-        ExportDatabaseConfigurationHandler handler = new ExportDatabaseConfigurationHandler().init(getParameter(createSQLStatement(), mock(ConnectionSession.class)));
+        ExportDatabaseConfigurationHandler handler = new ExportDatabaseConfigurationHandler().init(createParameter(createSQLStatement(), mock(ConnectionSession.class)));
         handler.execute();
         handler.next();
         List<Object> data = new ArrayList<>(handler.getRowData());
@@ -119,11 +118,9 @@ public final class ExportDatabaseConfigurationHandlerTest {
     }
     
     private Map<String, TableMetaData> createTableMap() {
-        Map<String, TableMetaData> result = new HashMap<>(1, 1);
         List<ColumnMetaData> columns = Collections.singletonList(new ColumnMetaData("order_id", 0, false, false, false));
         List<IndexMetaData> indexes = Collections.singletonList(new IndexMetaData("primary"));
-        result.put("t_order", new TableMetaData("t_order", columns, indexes, Collections.emptyList()));
-        return result;
+        return Collections.singletonMap("t_order", new TableMetaData("t_order", columns, indexes, Collections.emptyList()));
     }
     
     private ShardingTableRuleConfiguration createTableRuleConfiguration() {
@@ -136,7 +133,7 @@ public final class ExportDatabaseConfigurationHandlerTest {
         return new ExportDatabaseConfigurationStatement(new SchemaSegment(0, 0, new IdentifierValue("sharding_db")), null);
     }
     
-    private HandlerParameter<ExportDatabaseConfigurationStatement> getParameter(final ExportDatabaseConfigurationStatement statement, final ConnectionSession connectionSession) {
+    private HandlerParameter<ExportDatabaseConfigurationStatement> createParameter(final ExportDatabaseConfigurationStatement statement, final ConnectionSession connectionSession) {
         return new HandlerParameter<>(statement, new MySQLDatabaseType(), connectionSession);
     }
 }
diff --git a/shardingsphere-test/shardingsphere-rewrite-test/src/test/java/org/apache/shardingsphere/sharding/rewrite/parameterized/scenario/MixSQLRewriterParameterizedTest.java b/shardingsphere-test/shardingsphere-rewrite-test/src/test/java/org/apache/shardingsphere/sharding/rewrite/parameterized/scenario/MixSQLRewriterParameterizedTest.java
index 7ccc3382476..deda6f71dcb 100644
--- a/shardingsphere-test/shardingsphere-rewrite-test/src/test/java/org/apache/shardingsphere/sharding/rewrite/parameterized/scenario/MixSQLRewriterParameterizedTest.java
+++ b/shardingsphere-test/shardingsphere-rewrite-test/src/test/java/org/apache/shardingsphere/sharding/rewrite/parameterized/scenario/MixSQLRewriterParameterizedTest.java
@@ -34,12 +34,10 @@ import javax.sql.DataSource;
 import java.io.File;
 import java.io.IOException;
 import java.net.URL;
-import java.sql.SQLException;
 import java.sql.Types;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.Map;
 
@@ -73,9 +71,7 @@ public final class MixSQLRewriterParameterizedTest extends AbstractSQLRewriterPa
         when(result.getAllTableNames()).thenReturn(Arrays.asList("t_account", "t_account_bak", "t_account_detail"));
         TableMetaData accountTableMetaData = mock(TableMetaData.class);
         when(accountTableMetaData.getColumns()).thenReturn(createColumnMetaDataMap());
-        Map<String, IndexMetaData> indexMetaDataMap = new HashMap<>(1, 1);
-        indexMetaDataMap.put("index_name", new IndexMetaData("index_name"));
-        when(accountTableMetaData.getIndexes()).thenReturn(indexMetaDataMap);
+        when(accountTableMetaData.getIndexes()).thenReturn(Collections.singletonMap("index_name", new IndexMetaData("index_name")));
         when(result.containsTable("t_account")).thenReturn(true);
         when(result.get("t_account")).thenReturn(accountTableMetaData);
         TableMetaData accountBakTableMetaData = mock(TableMetaData.class);
@@ -93,7 +89,7 @@ public final class MixSQLRewriterParameterizedTest extends AbstractSQLRewriterPa
     }
     
     @Override
-    protected void mockDataSource(final Map<String, DataSource> dataSources) throws SQLException {
+    protected void mockDataSource(final Map<String, DataSource> dataSources) {
     }
     
     private Map<String, ColumnMetaData> createColumnMetaDataMap() {
diff --git a/shardingsphere-test/shardingsphere-rewrite-test/src/test/java/org/apache/shardingsphere/sharding/rewrite/parameterized/scenario/ShardingSQLRewriterParameterizedTest.java b/shardingsphere-test/shardingsphere-rewrite-test/src/test/java/org/apache/shardingsphere/sharding/rewrite/parameterized/scenario/ShardingSQLRewriterParameterizedTest.java
index acdc26b9d16..b1e944e3b4f 100644
--- a/shardingsphere-test/shardingsphere-rewrite-test/src/test/java/org/apache/shardingsphere/sharding/rewrite/parameterized/scenario/ShardingSQLRewriterParameterizedTest.java
+++ b/shardingsphere-test/shardingsphere-rewrite-test/src/test/java/org/apache/shardingsphere/sharding/rewrite/parameterized/scenario/ShardingSQLRewriterParameterizedTest.java
@@ -35,13 +35,11 @@ import javax.sql.DataSource;
 import java.io.File;
 import java.io.IOException;
 import java.net.URL;
-import java.sql.SQLException;
 import java.sql.Types;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.Optional;
@@ -85,9 +83,7 @@ public final class ShardingSQLRewriterParameterizedTest extends AbstractSQLRewri
         when(result.getAllTableNames()).thenReturn(Arrays.asList("t_account", "t_account_detail"));
         TableMetaData accountTableMetaData = mock(TableMetaData.class);
         when(accountTableMetaData.getColumns()).thenReturn(createColumnMetaDataMap());
-        Map<String, IndexMetaData> indexMetaDataMap = new HashMap<>(1, 1);
-        indexMetaDataMap.put("status_idx_exist", new IndexMetaData("status_idx_exist"));
-        when(accountTableMetaData.getIndexes()).thenReturn(indexMetaDataMap);
+        when(accountTableMetaData.getIndexes()).thenReturn(Collections.singletonMap("status_idx_exist", new IndexMetaData("status_idx_exist")));
         when(accountTableMetaData.getPrimaryKeyColumns()).thenReturn(Collections.singletonList("account_id"));
         when(result.containsTable("t_account")).thenReturn(true);
         when(result.get("t_account")).thenReturn(accountTableMetaData);
@@ -108,6 +104,6 @@ public final class ShardingSQLRewriterParameterizedTest extends AbstractSQLRewri
     }
     
     @Override
-    protected void mockDataSource(final Map<String, DataSource> dataSources) throws SQLException {
+    protected void mockDataSource(final Map<String, DataSource> dataSources) {
     }
 }