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Posted to common-commits@hadoop.apache.org by sj...@apache.org on 2016/02/08 21:18:49 UTC

[2/4] hadoop git commit: YARN-4409. Fix javadoc and checkstyle issues in timelineservice code (Varun Saxena via sjlee)

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/TimelineWriter.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/TimelineWriter.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/TimelineWriter.java
index 50136de..663a18a 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/TimelineWriter.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/TimelineWriter.java
@@ -42,12 +42,13 @@ public interface TimelineWriter extends Service {
    * @param userId context user ID
    * @param flowName context flow name
    * @param flowVersion context flow version
-   * @param flowRunId
-   * @param appId context app ID
+   * @param flowRunId run id for the flow.
+   * @param appId context app ID.
    * @param data
    *          a {@link TimelineEntities} object.
    * @return a {@link TimelineWriteResponse} object.
-   * @throws IOException
+   * @throws IOException if there is any exception encountered while storing
+   *     or writing entities to the backend storage.
    */
   TimelineWriteResponse write(String clusterId, String userId,
       String flowName, String flowVersion, long flowRunId, String appId,
@@ -65,8 +66,11 @@ public interface TimelineWriter extends Service {
    *          a {@link TimelineEntity} object
    *          a {@link TimelineAggregationTrack} enum
    *          value.
+   * @param track Specifies the track or dimension along which aggregation would
+   *     occur. Includes USER, FLOW, QUEUE, etc.
    * @return a {@link TimelineWriteResponse} object.
-   * @throws IOException
+   * @throws IOException if there is any exception encountered while aggregating
+   *     entities to the backend storage.
    */
   TimelineWriteResponse aggregate(TimelineEntity data,
       TimelineAggregationTrack track) throws IOException;
@@ -76,7 +80,8 @@ public interface TimelineWriter extends Service {
    * written to the storage when the method returns. This may be a potentially
    * time-consuming operation, and should be used judiciously.
    *
-   * @throws IOException
+   * @throws IOException if there is any exception encountered while flushing
+   *     entities to the backend storage.
    */
   void flush() throws IOException;
 }
\ No newline at end of file

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationColumn.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationColumn.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationColumn.java
index c03c9b6..5734389 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationColumn.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationColumn.java
@@ -34,7 +34,7 @@ import org.apache.hadoop.yarn.server.timelineservice.storage.flow.Attribute;
 public enum ApplicationColumn implements Column<ApplicationTable> {
 
   /**
-   * App id
+   * App id.
    */
   ID(ApplicationColumnFamily.INFO, "id"),
 
@@ -84,7 +84,7 @@ public enum ApplicationColumn implements Column<ApplicationTable> {
   /**
    * Retrieve an {@link ApplicationColumn} given a name, or null if there is no
    * match. The following holds true: {@code columnFor(x) == columnFor(y)} if
-   * and only if {@code x.equals(y)} or {@code (x == y == null)}
+   * and only if {@code x.equals(y)} or {@code (x == y == null)}.
    *
    * @param columnQualifier Name of the column to retrieve
    * @return the corresponding {@link ApplicationColumn} or null

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationColumnPrefix.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationColumnPrefix.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationColumnPrefix.java
index 056e51f..9120f3d 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationColumnPrefix.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationColumnPrefix.java
@@ -54,7 +54,7 @@ public enum ApplicationColumnPrefix implements ColumnPrefix<ApplicationTable> {
   INFO(ApplicationColumnFamily.INFO, "i"),
 
   /**
-   * Lifecycle events for an application
+   * Lifecycle events for an application.
    */
   EVENT(ApplicationColumnFamily.INFO, "e"),
 
@@ -214,7 +214,7 @@ public enum ApplicationColumnPrefix implements ColumnPrefix<ApplicationTable> {
    *         is to facilitate returning byte arrays of values that were not
    *         Strings. If they can be treated as Strings, you should use
    *         {@link #readResults(Result)} instead.
-   * @throws IOException
+   * @throws IOException if any problem occurs while reading results.
    */
   public Map<?, Object> readResultsHavingCompoundColumnQualifiers(Result result)
       throws IOException {
@@ -276,8 +276,8 @@ public enum ApplicationColumnPrefix implements ColumnPrefix<ApplicationTable> {
     for (ApplicationColumnPrefix acp : ApplicationColumnPrefix.values()) {
       // Find a match based column family and on name.
       if (acp.columnFamily.equals(columnFamily)
-          && (((columnPrefix == null) && (acp.getColumnPrefix() == null)) || (acp
-              .getColumnPrefix().equals(columnPrefix)))) {
+          && (((columnPrefix == null) && (acp.getColumnPrefix() == null)) ||
+          (acp.getColumnPrefix().equals(columnPrefix)))) {
         return acp;
       }
     }

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationRowKey.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationRowKey.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationRowKey.java
index 3c182b9..ad2aa7a 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationRowKey.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationRowKey.java
@@ -62,11 +62,11 @@ public class ApplicationRowKey {
 
   /**
    * Constructs a row key prefix for the application table as follows:
-   * {@code clusterId!userName!flowName!}
+   * {@code clusterId!userName!flowName!}.
    *
-   * @param clusterId
-   * @param userId
-   * @param flowName
+   * @param clusterId Cluster Id.
+   * @param userId User Id.
+   * @param flowName Flow Name.
    * @return byte array with the row key prefix
    */
   public static byte[] getRowKeyPrefix(String clusterId, String userId,
@@ -78,12 +78,12 @@ public class ApplicationRowKey {
 
   /**
    * Constructs a row key prefix for the application table as follows:
-   * {@code clusterId!userName!flowName!flowRunId!}
+   * {@code clusterId!userName!flowName!flowRunId!}.
    *
-   * @param clusterId
-   * @param userId
-   * @param flowName
-   * @param flowRunId
+   * @param clusterId Cluster Id.
+   * @param userId User Id.
+   * @param flowName Flow Name.
+   * @param flowRunId Run Id for the flow.
    * @return byte array with the row key prefix
    */
   public static byte[] getRowKeyPrefix(String clusterId, String userId,
@@ -96,13 +96,13 @@ public class ApplicationRowKey {
 
   /**
    * Constructs a row key for the application table as follows:
-   * {@code clusterId!userName!flowName!flowRunId!AppId}
+   * {@code clusterId!userName!flowName!flowRunId!AppId}.
    *
-   * @param clusterId
-   * @param userId
-   * @param flowName
-   * @param flowRunId
-   * @param appId
+   * @param clusterId Cluster Id.
+   * @param userId User Id.
+   * @param flowName Flow Name.
+   * @param flowRunId Run Id for the flow.
+   * @param appId App Id.
    * @return byte array with the row key
    */
   public static byte[] getRowKey(String clusterId, String userId,
@@ -119,6 +119,9 @@ public class ApplicationRowKey {
 
   /**
    * Given the raw row key as bytes, returns the row key as an object.
+   *
+   * @param rowKey Byte representation  of row key.
+   * @return An <cite>ApplicationRowKey</cite> object.
    */
   public static ApplicationRowKey parseRowKey(byte[] rowKey) {
     byte[][] rowKeyComponents = Separator.QUALIFIERS.split(rowKey);

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationTable.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationTable.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationTable.java
index 681c200..a02f768 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationTable.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/ApplicationTable.java
@@ -68,28 +68,28 @@ import org.apache.hadoop.yarn.server.timelineservice.storage.common.TimelineHBas
  * </pre>
  */
 public class ApplicationTable extends BaseTable<ApplicationTable> {
-  /** application prefix */
+  /** application prefix. */
   private static final String PREFIX =
       YarnConfiguration.TIMELINE_SERVICE_PREFIX + ".application";
 
-  /** config param name that specifies the application table name */
+  /** config param name that specifies the application table name. */
   public static final String TABLE_NAME_CONF_NAME = PREFIX + ".table.name";
 
   /**
    * config param name that specifies the TTL for metrics column family in
-   * application table
+   * application table.
    */
   private static final String METRICS_TTL_CONF_NAME = PREFIX
       + ".table.metrics.ttl";
 
-  /** default value for application table name */
+  /** default value for application table name. */
   private static final String DEFAULT_TABLE_NAME =
       "timelineservice.application";
 
-  /** default TTL is 30 days for metrics timeseries */
+  /** default TTL is 30 days for metrics timeseries. */
   private static final int DEFAULT_METRICS_TTL = 2592000;
 
-  /** default max number of versions */
+  /** default max number of versions. */
   private static final int DEFAULT_METRICS_MAX_VERSIONS = 1000;
 
   private static final Log LOG = LogFactory.getLog(ApplicationTable.class);
@@ -139,8 +139,8 @@ public class ApplicationTable extends BaseTable<ApplicationTable> {
     metricsCF.setMaxVersions(DEFAULT_METRICS_MAX_VERSIONS);
     metricsCF.setTimeToLive(hbaseConf.getInt(METRICS_TTL_CONF_NAME,
         DEFAULT_METRICS_TTL));
-    applicationTableDescp
-        .setRegionSplitPolicyClassName("org.apache.hadoop.hbase.regionserver.KeyPrefixRegionSplitPolicy");
+    applicationTableDescp.setRegionSplitPolicyClassName(
+        "org.apache.hadoop.hbase.regionserver.KeyPrefixRegionSplitPolicy");
     applicationTableDescp.setValue("KeyPrefixRegionSplitPolicy.prefix_length",
         TimelineHBaseSchemaConstants.USERNAME_SPLIT_KEY_PREFIX_LENGTH);
     admin.createTable(applicationTableDescp,

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/package-info.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/package-info.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/package-info.java
index c60e6f5..eda14e6 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/package-info.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/application/package-info.java
@@ -16,6 +16,10 @@
  * limitations under the License.
  */
 
+/**
+ * Package org.apache.hadoop.yarn.server.timelineservice.storage.application
+ * contains classes related to implementation for application table.
+ */
 @InterfaceAudience.Private
 @InterfaceStability.Unstable
 package org.apache.hadoop.yarn.server.timelineservice.storage.application;

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowColumn.java
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diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowColumn.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowColumn.java
index 7f1ecaf..a8e1c66 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowColumn.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowColumn.java
@@ -35,17 +35,17 @@ import java.io.IOException;
 public enum AppToFlowColumn implements Column<AppToFlowTable> {
 
   /**
-   * The flow ID
+   * The flow ID.
    */
   FLOW_ID(AppToFlowColumnFamily.MAPPING, "flow_id"),
 
   /**
-   * The flow run ID
+   * The flow run ID.
    */
   FLOW_RUN_ID(AppToFlowColumnFamily.MAPPING, "flow_run_id"),
 
   /**
-   * The user
+   * The user.
    */
   USER_ID(AppToFlowColumnFamily.MAPPING, "user_id");
 

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowColumnFamily.java
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diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowColumnFamily.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowColumnFamily.java
index d722d15..f3f045e 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowColumnFamily.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowColumnFamily.java
@@ -26,7 +26,7 @@ import org.apache.hadoop.yarn.server.timelineservice.storage.common.Separator;
  */
 public enum AppToFlowColumnFamily implements ColumnFamily<AppToFlowTable> {
   /**
-   * Mapping column family houses known columns such as flowName and flowRunId
+   * Mapping column family houses known columns such as flowName and flowRunId.
    */
   MAPPING("m");
 

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowRowKey.java
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diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowRowKey.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowRowKey.java
index 133952e..3085bb1 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowRowKey.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowRowKey.java
@@ -43,10 +43,10 @@ public class AppToFlowRowKey {
 
   /**
    * Constructs a row key prefix for the app_flow table as follows:
-   * {@code clusterId!AppId}
+   * {@code clusterId!AppId}.
    *
-   * @param clusterId
-   * @param appId
+   * @param clusterId Cluster Id.
+   * @param appId Application Id.
    * @return byte array with the row key
    */
   public static byte[] getRowKey(String clusterId, String appId) {
@@ -57,6 +57,9 @@ public class AppToFlowRowKey {
 
   /**
    * Given the raw row key as bytes, returns the row key as an object.
+   *
+   * @param rowKey a rowkey represented as a byte array.
+   * @return an <cite>AppToFlowRowKey</cite> object.
    */
   public static AppToFlowRowKey parseRowKey(byte[] rowKey) {
     byte[][] rowKeyComponents = Separator.QUALIFIERS.split(rowKey);

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowTable.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowTable.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowTable.java
index 868c6f3..301cf99 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowTable.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/AppToFlowTable.java
@@ -58,14 +58,14 @@ import java.io.IOException;
  * </pre>
  */
 public class AppToFlowTable extends BaseTable<AppToFlowTable> {
-  /** app_flow prefix */
+  /** app_flow prefix. */
   private static final String PREFIX =
       YarnConfiguration.TIMELINE_SERVICE_PREFIX + "app-flow";
 
-  /** config param name that specifies the app_flow table name */
+  /** config param name that specifies the app_flow table name. */
   public static final String TABLE_NAME_CONF_NAME = PREFIX + ".table.name";
 
-  /** default value for app_flow table name */
+  /** default value for app_flow table name. */
   private static final String DEFAULT_TABLE_NAME = "timelineservice.app_flow";
 
   private static final Log LOG = LogFactory.getLog(AppToFlowTable.class);

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/package-info.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/package-info.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/package-info.java
index df7ffc1..f01d982 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/package-info.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/apptoflow/package-info.java
@@ -15,6 +15,11 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
+/**
+ * Package org.apache.hadoop.yarn.server.timelineservice.storage.apptoflow
+ * contains classes related to implementation for app to flow table.
+ */
 @InterfaceAudience.Private
 @InterfaceStability.Unstable
 package org.apache.hadoop.yarn.server.timelineservice.storage.apptoflow;

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/BaseTable.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/BaseTable.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/BaseTable.java
index 9545438..8581aa4 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/BaseTable.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/BaseTable.java
@@ -39,7 +39,7 @@ import org.apache.hadoop.hbase.client.Table;
 public abstract class BaseTable<T> {
 
   /**
-   * Name of config variable that is used to point to this table
+   * Name of config variable that is used to point to this table.
    */
   private final String tableNameConfName;
 
@@ -52,6 +52,8 @@ public abstract class BaseTable<T> {
   /**
    * @param tableNameConfName name of config variable that is used to point to
    *          this table.
+   * @param defaultTableName Default table name if table from config is not
+   *          found.
    */
   protected BaseTable(String tableNameConfName, String defaultTableName) {
     this.tableNameConfName = tableNameConfName;
@@ -61,10 +63,11 @@ public abstract class BaseTable<T> {
   /**
    * Used to create a type-safe mutator for this table.
    *
-   * @param hbaseConf used to read table name
+   * @param hbaseConf used to read table name.
    * @param conn used to create a table from.
    * @return a type safe {@link BufferedMutator} for the entity table.
-   * @throws IOException
+   * @throws IOException if any exception occurs while creating mutator for the
+   *     table.
    */
   public TypedBufferedMutator<T> getTableMutator(Configuration hbaseConf,
       Connection conn) throws IOException {
@@ -88,7 +91,7 @@ public abstract class BaseTable<T> {
    * @param conn used to create table from
    * @param scan that specifies what you want to read from this table.
    * @return scanner for the table.
-   * @throws IOException
+   * @throws IOException if any exception occurs while getting the scanner.
    */
   public ResultScanner getResultScanner(Configuration hbaseConf,
       Connection conn, Scan scan) throws IOException {
@@ -102,7 +105,7 @@ public abstract class BaseTable<T> {
    * @param conn used to create table from
    * @param get that specifies what single row you want to get from this table
    * @return result of get operation
-   * @throws IOException
+   * @throws IOException if any exception occurs while getting the result.
    */
   public Result getResult(Configuration hbaseConf, Connection conn, Get get)
       throws IOException {
@@ -113,7 +116,8 @@ public abstract class BaseTable<T> {
   /**
    * Get the table name for this table.
    *
-   * @param hbaseConf
+   * @param hbaseConf HBase configuration from which table name will be fetched.
+   * @return A {@link TableName} object.
    */
   public TableName getTableName(Configuration hbaseConf) {
     TableName table =
@@ -126,8 +130,9 @@ public abstract class BaseTable<T> {
    * Used to create the table in HBase. Should be called only once (per HBase
    * instance).
    *
-   * @param admin
-   * @param hbaseConf
+   * @param admin Used for doing HBase table operations.
+   * @param hbaseConf Hbase configuration.
+   * @throws IOException if any exception occurs while creating the table.
    */
   public abstract void createTable(Admin admin, Configuration hbaseConf)
       throws IOException;

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/BufferedMutatorDelegator.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/BufferedMutatorDelegator.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/BufferedMutatorDelegator.java
index fe8f9c6..cf469a5 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/BufferedMutatorDelegator.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/BufferedMutatorDelegator.java
@@ -26,7 +26,7 @@ import org.apache.hadoop.hbase.client.BufferedMutator;
 import org.apache.hadoop.hbase.client.Mutation;
 
 /**
- * To be used to wrap an actual {@link BufferedMutator} in a type safe manner
+ * To be used to wrap an actual {@link BufferedMutator} in a type safe manner.
  *
  * @param <T> The class referring to the table to be written to.
  */

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/Column.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/Column.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/Column.java
index 64c1cda..1f0b48f 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/Column.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/Column.java
@@ -19,7 +19,6 @@ package org.apache.hadoop.yarn.server.timelineservice.storage.common;
 
 import java.io.IOException;
 
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.client.Result;
 import org.apache.hadoop.yarn.server.timelineservice.storage.flow.Attribute;
 
@@ -39,25 +38,26 @@ public interface Column<T> {
    *          column.
    * @param timestamp version timestamp. When null the server timestamp will be
    *          used.
-   * @param attributes Map of attributes for this mutation. used in the coprocessor
-   *          to set/read the cell tags. Can be null.
+   * @param attributes Map of attributes for this mutation. used in the
+   *     coprocessor to set/read the cell tags. Can be null.
    * @param inputValue the value to write to the rowKey and column qualifier.
    *          Nothing gets written when null.
-   * @throws IOException
+   * @throws IOException if there is any exception encountered during store.
    */
-  public void store(byte[] rowKey, TypedBufferedMutator<T> tableMutator,
+  void store(byte[] rowKey, TypedBufferedMutator<T> tableMutator,
       Long timestamp, Object inputValue, Attribute... attributes)
       throws IOException;
 
   /**
    * Get the latest version of this specified column. Note: this call clones the
-   * value content of the hosting {@link Cell}.
+   * value content of the hosting {@link org.apache.hadoop.hbase.Cell Cell}.
    *
    * @param result Cannot be null
    * @return result object (can be cast to whatever object was written to), or
    *         null when result doesn't contain this column.
-   * @throws IOException
+   * @throws IOException if there is any exception encountered while reading
+   *     result.
    */
-  public Object readResult(Result result) throws IOException;
+  Object readResult(Result result) throws IOException;
 
 }
\ No newline at end of file

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ColumnFamily.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ColumnFamily.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ColumnFamily.java
index c84c016..452adcd 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ColumnFamily.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ColumnFamily.java
@@ -29,6 +29,6 @@ public interface ColumnFamily<T> {
    *
    * @return a clone of the byte representation of the column family.
    */
-  public byte[] getBytes();
+  byte[] getBytes();
 
 }
\ No newline at end of file

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ColumnHelper.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ColumnHelper.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ColumnHelper.java
index 1e63ce5..15bb818 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ColumnHelper.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ColumnHelper.java
@@ -26,7 +26,6 @@ import java.util.TreeMap;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.client.Put;
 import org.apache.hadoop.hbase.client.Result;
 import org.apache.hadoop.hbase.util.Bytes;
@@ -82,7 +81,9 @@ public class ColumnHelper<T> {
    * @param inputValue
    *          the value to write to the rowKey and column qualifier. Nothing
    *          gets written when null.
-   * @throws IOException
+   * @param attributes Attributes to be set for HBase Put.
+   * @throws IOException if any problem occurs during store operation(sending
+   *          mutation to table).
    */
   public void store(byte[] rowKey, TypedBufferedMutator<?> tableMutator,
       byte[] columnQualifier, Long timestamp, Object inputValue,
@@ -140,13 +141,13 @@ public class ColumnHelper<T> {
 
   /**
    * Get the latest version of this specified column. Note: this call clones the
-   * value content of the hosting {@link Cell}.
+   * value content of the hosting {@link org.apache.hadoop.hbase.Cell Cell}.
    *
    * @param result from which to read the value. Cannot be null
    * @param columnQualifierBytes referring to the column to be read.
    * @return latest version of the specified column of whichever object was
    *         written.
-   * @throws IOException
+   * @throws IOException if any problem occurs while reading result.
    */
   public Object readResult(Result result, byte[] columnQualifierBytes)
       throws IOException {
@@ -167,9 +168,9 @@ public class ColumnHelper<T> {
    *          columns are returned.
    * @param <V> the type of the values. The values will be cast into that type.
    * @return the cell values at each respective time in for form
-   *         {idA={timestamp1->value1}, idA={timestamp2->value2},
-   *         idB={timestamp3->value3}, idC={timestamp1->value4}}
-   * @throws IOException
+   *         {@literal {idA={timestamp1->value1}, idA={timestamp2->value2},
+   *         idB={timestamp3->value3}, idC={timestamp1->value4}}}
+   * @throws IOException if any problem occurs while reading results.
    */
   @SuppressWarnings("unchecked")
   public <V> NavigableMap<String, NavigableMap<Long, V>>
@@ -180,8 +181,9 @@ public class ColumnHelper<T> {
         new TreeMap<String, NavigableMap<Long, V>>();
 
     if (result != null) {
-      NavigableMap<byte[], NavigableMap<byte[], NavigableMap<Long, byte[]>>> resultMap =
-          result.getMap();
+      NavigableMap<
+          byte[], NavigableMap<byte[], NavigableMap<Long, byte[]>>> resultMap =
+              result.getMap();
 
       NavigableMap<byte[], NavigableMap<Long, byte[]>> columnCellMap =
           resultMap.get(columnFamilyBytes);
@@ -240,7 +242,7 @@ public class ColumnHelper<T> {
    *         back and forth from Strings, you should use
    *         {@link #readResultsHavingCompoundColumnQualifiers(Result, byte[])}
    *         instead.
-   * @throws IOException
+   * @throws IOException if any problem occurs while reading results.
    */
   public Map<String, Object> readResults(Result result,
       byte[] columnPrefixBytes) throws IOException {
@@ -294,7 +296,7 @@ public class ColumnHelper<T> {
    *         non-null column prefix bytes, the column qualifier is returned as
    *         a list of parts, each part a byte[]. This is to facilitate
    *         returning byte arrays of values that were not Strings.
-   * @throws IOException
+   * @throws IOException if any problem occurs while reading results.
    */
   public Map<?, Object> readResultsHavingCompoundColumnQualifiers(Result result,
       byte[] columnPrefixBytes) throws IOException {

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ColumnPrefix.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ColumnPrefix.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ColumnPrefix.java
index 0f3ac4e..f221b31 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ColumnPrefix.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ColumnPrefix.java
@@ -21,7 +21,6 @@ import java.io.IOException;
 import java.util.Map;
 import java.util.NavigableMap;
 
-import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.client.Result;
 import org.apache.hadoop.yarn.server.timelineservice.storage.flow.Attribute;
 
@@ -48,7 +47,8 @@ public interface ColumnPrefix<T> {
    *          coprocessor to set/read the cell tags.
    * @param inputValue the value to write to the rowKey and column qualifier.
    *          Nothing gets written when null.
-   * @throws IOException
+   * @throws IOException if there is any exception encountered while doing
+   *     store operation(sending mutation to the table).
    */
   void store(byte[] rowKey, TypedBufferedMutator<T> tableMutator,
       byte[] qualifier, Long timestamp, Object inputValue,
@@ -69,7 +69,8 @@ public interface ColumnPrefix<T> {
    *          coprocessor to set/read the cell tags.
    * @param inputValue the value to write to the rowKey and column qualifier.
    *          Nothing gets written when null.
-   * @throws IOException
+   * @throws IOException if there is any exception encountered while doing
+   *     store operation(sending mutation to the table).
    */
   void store(byte[] rowKey, TypedBufferedMutator<T> tableMutator,
       String qualifier, Long timestamp, Object inputValue,
@@ -77,14 +78,15 @@ public interface ColumnPrefix<T> {
 
   /**
    * Get the latest version of this specified column. Note: this call clones the
-   * value content of the hosting {@link Cell}.
+   * value content of the hosting {@link org.apache.hadoop.hbase.Cell Cell}.
    *
    * @param result Cannot be null
    * @param qualifier column qualifier. Nothing gets read when null.
    * @return result object (can be cast to whatever object was written to) or
    *         null when specified column qualifier for this prefix doesn't exist
    *         in the result.
-   * @throws IOException
+   * @throws IOException if there is any exception encountered while reading
+   *     result.
    */
   Object readResult(Result result, String qualifier) throws IOException;
 
@@ -92,7 +94,8 @@ public interface ColumnPrefix<T> {
    * @param result from which to read columns
    * @return the latest values of columns in the column family with this prefix
    *         (or all of them if the prefix value is null).
-   * @throws IOException
+   * @throws IOException if there is any exception encountered while reading
+   *     results.
    */
   Map<String, Object> readResults(Result result) throws IOException;
 
@@ -100,9 +103,10 @@ public interface ColumnPrefix<T> {
    * @param result from which to reads data with timestamps
    * @param <V> the type of the values. The values will be cast into that type.
    * @return the cell values at each respective time in for form
-   *         {idA={timestamp1->value1}, idA={timestamp2->value2},
-   *         idB={timestamp3->value3}, idC={timestamp1->value4}}
-   * @throws IOException
+   *         {@literal {idA={timestamp1->value1}, idA={timestamp2->value2},
+   *         idB={timestamp3->value3}, idC={timestamp1->value4}}}
+   * @throws IOException if there is any exception encountered while reading
+   *     result.
    */
   <V> NavigableMap<String, NavigableMap<Long, V>>
       readResultsWithTimestamps(Result result) throws IOException;

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/LongConverter.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/LongConverter.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/LongConverter.java
index cdb8619..48c56f9 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/LongConverter.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/LongConverter.java
@@ -55,8 +55,9 @@ public final class LongConverter implements NumericValueConverter {
   /**
    * Compares two numbers as longs. If either number is null, it will be taken
    * as 0.
-   * @param num1
-   * @param num2
+   *
+   * @param num1 the first {@code Long} to compare.
+   * @param num2 the second {@code Long} to compare.
    * @return -1 if num1 is less than num2, 0 if num1 is equal to num2 and 1 if
    * num1 is greater than num2.
    */

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/NumericValueConverter.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/NumericValueConverter.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/NumericValueConverter.java
index 70964cd..8fb6536 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/NumericValueConverter.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/NumericValueConverter.java
@@ -29,9 +29,10 @@ public interface NumericValueConverter extends ValueConverter,
   /**
    * Adds two or more numbers. If either of the numbers are null, it is taken as
    * 0.
-   * @param num1
-   * @param num2
-   * @param numbers
+   *
+   * @param num1 the first number to add.
+   * @param num2 the second number to add.
+   * @param numbers Rest of the numbers to be added.
    * @return result after adding up the numbers.
    */
   Number add(Number num1, Number num2, Number...numbers);

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/OfflineAggregationInfo.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/OfflineAggregationInfo.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/OfflineAggregationInfo.java
index 16c03a3..3dc5f51 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/OfflineAggregationInfo.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/OfflineAggregationInfo.java
@@ -33,21 +33,24 @@ import java.sql.SQLException;
  */
 public final class OfflineAggregationInfo {
   /**
-   * Default flow level aggregation table name
+   * Default flow level aggregation table name.
    */
   @VisibleForTesting
   public static final String FLOW_AGGREGATION_TABLE_NAME
       = "yarn_timeline_flow_aggregation";
   /**
-   * Default user level aggregation table name
+   * Default user level aggregation table name.
    */
   public static final String USER_AGGREGATION_TABLE_NAME
       = "yarn_timeline_user_aggregation";
 
   // These lists are not taking effects in table creations.
-  private static final String[] FLOW_AGGREGATION_PK_LIST =
-      { "user", "cluster", "flow_name" };
-  private static final String[] USER_AGGREGATION_PK_LIST = { "user", "cluster"};
+  private static final String[] FLOW_AGGREGATION_PK_LIST = {
+      "user", "cluster", "flow_name"
+  };
+  private static final String[] USER_AGGREGATION_PK_LIST = {
+      "user", "cluster"
+  };
 
   private final String tableName;
   private final String[] primaryKeyList;
@@ -81,30 +84,32 @@ public final class OfflineAggregationInfo {
 
   public static final OfflineAggregationInfo FLOW_AGGREGATION =
       new OfflineAggregationInfo(FLOW_AGGREGATION_TABLE_NAME,
-          FLOW_AGGREGATION_PK_LIST, new PrimaryKeyStringSetter() {
-        @Override
-        public int setValues(PreparedStatement ps,
-            TimelineCollectorContext context, String[] extraInfo, int startPos)
-            throws SQLException {
-          int idx = startPos;
-          ps.setString(idx++, context.getUserId());
-          ps.setString(idx++, context.getClusterId());
-          ps.setString(idx++, context.getFlowName());
-          return idx;
-        }
-      });
+          FLOW_AGGREGATION_PK_LIST,
+          new PrimaryKeyStringSetter() {
+          @Override
+          public int setValues(PreparedStatement ps,
+              TimelineCollectorContext context, String[] extraInfo,
+              int startPos) throws SQLException {
+            int idx = startPos;
+            ps.setString(idx++, context.getUserId());
+            ps.setString(idx++, context.getClusterId());
+            ps.setString(idx++, context.getFlowName());
+            return idx;
+          }
+        });
 
   public static final OfflineAggregationInfo USER_AGGREGATION =
       new OfflineAggregationInfo(USER_AGGREGATION_TABLE_NAME,
-          USER_AGGREGATION_PK_LIST, new PrimaryKeyStringSetter() {
-        @Override
-        public int setValues(PreparedStatement ps,
-            TimelineCollectorContext context, String[] extraInfo, int startPos)
-            throws SQLException {
-          int idx = startPos;
-          ps.setString(idx++, context.getUserId());
-          ps.setString(idx++, context.getClusterId());
-          return idx;
-        }
-      });
+          USER_AGGREGATION_PK_LIST,
+          new PrimaryKeyStringSetter() {
+          @Override
+          public int setValues(PreparedStatement ps,
+              TimelineCollectorContext context, String[] extraInfo,
+              int startPos) throws SQLException {
+            int idx = startPos;
+            ps.setString(idx++, context.getUserId());
+            ps.setString(idx++, context.getClusterId());
+            return idx;
+          }
+        });
 }

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/Range.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/Range.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/Range.java
index 2cb6c08..8a2e01a 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/Range.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/Range.java
@@ -20,6 +20,9 @@ package org.apache.hadoop.yarn.server.timelineservice.storage.common;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
 
+/**
+ * Encapsulates a range with start and end indices.
+ */
 @InterfaceAudience.Private
 @InterfaceStability.Unstable
 public class Range {

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/Separator.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/Separator.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/Separator.java
index 1e82494..a81c717 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/Separator.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/Separator.java
@@ -30,7 +30,7 @@ import org.apache.hadoop.hbase.util.Bytes;
 public enum Separator {
 
   /**
-   * separator in key or column qualifier fields
+   * separator in key or column qualifier fields.
    */
   QUALIFIERS("!", "%0$"),
 
@@ -53,7 +53,7 @@ public enum Separator {
   private final String value;
 
   /**
-   * The URLEncoded version of this separator
+   * The URLEncoded version of this separator.
    */
   private final String encodedValue;
 
@@ -63,7 +63,7 @@ public enum Separator {
   private final byte[] bytes;
 
   /**
-   * The value quoted so that it can be used as a safe regex
+   * The value quoted so that it can be used as a safe regex.
    */
   private final String quotedValue;
 
@@ -99,7 +99,7 @@ public enum Separator {
   /**
    * Used to make token safe to be used with this separator without collisions.
    *
-   * @param token
+   * @param token Token to be encoded.
    * @return the token with any occurrences of this separator URLEncoded.
    */
   public String encode(String token) {
@@ -111,7 +111,9 @@ public enum Separator {
   }
 
   /**
-   * @param token
+   * Decode the token encoded using {@link #encode}.
+   *
+   * @param token Token to be decoded.
    * @return the token with any occurrences of the encoded separator replaced by
    *         the separator itself.
    */
@@ -193,7 +195,7 @@ public enum Separator {
    * Returns a single byte array containing all of the individual arrays
    * components separated by this separator.
    *
-   * @param components
+   * @param components Byte array components to be joined together.
    * @return byte array after joining the components
    */
   public byte[] join(byte[]... components) {
@@ -287,8 +289,8 @@ public enum Separator {
   public Collection<String> splitEncoded(String compoundValue) {
     List<String> result = new ArrayList<String>();
     if (compoundValue != null) {
-      for (String value : compoundValue.split(quotedValue)) {
-        result.add(decode(value));
+      for (String val : compoundValue.split(quotedValue)) {
+        result.add(decode(val));
       }
     }
     return result;
@@ -298,6 +300,7 @@ public enum Separator {
    * Splits the source array into multiple array segments using this separator,
    * up to a maximum of count items. This will naturally produce copied byte
    * arrays for each of the split segments.
+   *
    * @param source to be split
    * @param limit on how many segments are supposed to be returned. A
    *          non-positive value indicates no limit on number of segments.
@@ -311,6 +314,7 @@ public enum Separator {
    * Splits the source array into multiple array segments using this separator,
    * as many times as splits are found. This will naturally produce copied byte
    * arrays for each of the split segments.
+   *
    * @param source to be split
    * @return source split by this separator.
    */

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/TimelineHBaseSchemaConstants.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/TimelineHBaseSchemaConstants.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/TimelineHBaseSchemaConstants.java
index bbf498a..8e6c259 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/TimelineHBaseSchemaConstants.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/TimelineHBaseSchemaConstants.java
@@ -24,11 +24,13 @@ import org.apache.hadoop.hbase.util.Bytes;
 /**
  * contains the constants used in the context of schema accesses for
  * {@link org.apache.hadoop.yarn.api.records.timelineservice.TimelineEntity}
- * information
+ * information.
  */
 @InterfaceAudience.Private
 @InterfaceStability.Unstable
-public class TimelineHBaseSchemaConstants {
+public final class TimelineHBaseSchemaConstants {
+  private TimelineHBaseSchemaConstants() {
+  }
 
   /**
    * Used to create a pre-split for tables starting with a username in the
@@ -36,27 +38,28 @@ public class TimelineHBaseSchemaConstants {
    * separators) so that different installations can presplit based on their own
    * commonly occurring names.
    */
-  private final static byte[][] USERNAME_SPLITS = { Bytes.toBytes("a"),
-      Bytes.toBytes("ad"), Bytes.toBytes("an"), Bytes.toBytes("b"),
-      Bytes.toBytes("ca"), Bytes.toBytes("cl"), Bytes.toBytes("d"),
-      Bytes.toBytes("e"), Bytes.toBytes("f"), Bytes.toBytes("g"),
-      Bytes.toBytes("h"), Bytes.toBytes("i"), Bytes.toBytes("j"),
-      Bytes.toBytes("k"), Bytes.toBytes("l"), Bytes.toBytes("m"),
-      Bytes.toBytes("n"), Bytes.toBytes("o"), Bytes.toBytes("q"),
-      Bytes.toBytes("r"), Bytes.toBytes("s"), Bytes.toBytes("se"),
-      Bytes.toBytes("t"), Bytes.toBytes("u"), Bytes.toBytes("v"),
-      Bytes.toBytes("w"), Bytes.toBytes("x"), Bytes.toBytes("y"),
-      Bytes.toBytes("z") };
+  private final static byte[][] USERNAME_SPLITS = {
+      Bytes.toBytes("a"), Bytes.toBytes("ad"), Bytes.toBytes("an"),
+      Bytes.toBytes("b"), Bytes.toBytes("ca"), Bytes.toBytes("cl"),
+      Bytes.toBytes("d"), Bytes.toBytes("e"), Bytes.toBytes("f"),
+      Bytes.toBytes("g"), Bytes.toBytes("h"), Bytes.toBytes("i"),
+      Bytes.toBytes("j"), Bytes.toBytes("k"), Bytes.toBytes("l"),
+      Bytes.toBytes("m"), Bytes.toBytes("n"), Bytes.toBytes("o"),
+      Bytes.toBytes("q"), Bytes.toBytes("r"), Bytes.toBytes("s"),
+      Bytes.toBytes("se"), Bytes.toBytes("t"), Bytes.toBytes("u"),
+      Bytes.toBytes("v"), Bytes.toBytes("w"), Bytes.toBytes("x"),
+      Bytes.toBytes("y"), Bytes.toBytes("z")
+  };
 
   /**
-   * The length at which keys auto-split
+   * The length at which keys auto-split.
    */
   public static final String USERNAME_SPLIT_KEY_PREFIX_LENGTH = "4";
 
   /**
    * @return splits for splits where a user is a prefix.
    */
-  public final static byte[][] getUsernameSplits() {
+  public static byte[][] getUsernameSplits() {
     byte[][] kloon = USERNAME_SPLITS.clone();
     // Deep copy.
     for (int row = 0; row < USERNAME_SPLITS.length; row++) {

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/TimelineStorageUtils.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/TimelineStorageUtils.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/TimelineStorageUtils.java
index e30f699..2328bba 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/TimelineStorageUtils.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/TimelineStorageUtils.java
@@ -45,15 +45,17 @@ import org.apache.hadoop.yarn.util.ConverterUtils;
  */
 @Public
 @Unstable
-public class TimelineStorageUtils {
+public final class TimelineStorageUtils {
+  private TimelineStorageUtils() {
+  }
 
-  /** empty bytes */
+  /** empty bytes. */
   public static final byte[] EMPTY_BYTES = new byte[0];
 
-  /** indicator for no limits for splitting */
+  /** indicator for no limits for splitting. */
   public static final int NO_LIMIT_SPLIT = -1;
 
-  /** milliseconds in one day */
+  /** milliseconds in one day. */
   public static final long MILLIS_ONE_DAY = 86400000L;
 
   /**
@@ -62,9 +64,9 @@ public class TimelineStorageUtils {
    * copied byte arrays for each of the split segments. To identify the split
    * ranges without the array copies, see {@link #splitRanges(byte[], byte[])}.
    *
-   * @param source
-   * @param separator
-   * @return byte[] array after splitting the source
+   * @param source Source array.
+   * @param separator Separator represented as a byte array.
+   * @return byte[][] after splitting the source
    */
   public static byte[][] split(byte[] source, byte[] separator) {
     return split(source, separator, NO_LIMIT_SPLIT);
@@ -76,10 +78,10 @@ public class TimelineStorageUtils {
    * copied byte arrays for each of the split segments. To identify the split
    * ranges without the array copies, see {@link #splitRanges(byte[], byte[])}.
    *
-   * @param source
-   * @param separator
+   * @param source Source array.
+   * @param separator Separator represented as a byte array.
    * @param limit a non-positive value indicates no limit on number of segments.
-   * @return byte[][] after splitting the input source
+   * @return byte[][] after splitting the input source.
    */
   public static byte[][] split(byte[] source, byte[] separator, int limit) {
     List<Range> segments = splitRanges(source, separator, limit);
@@ -100,6 +102,10 @@ public class TimelineStorageUtils {
    * Returns a list of ranges identifying [start, end) -- closed, open --
    * positions within the source byte array that would be split using the
    * separator byte array.
+   *
+   * @param source Source array.
+   * @param separator Separator represented as a byte array.
+   * @return a list of ranges.
    */
   public static List<Range> splitRanges(byte[] source, byte[] separator) {
     return splitRanges(source, separator, NO_LIMIT_SPLIT);
@@ -113,6 +119,7 @@ public class TimelineStorageUtils {
    * @param source the source data
    * @param separator the separator pattern to look for
    * @param limit the maximum number of splits to identify in the source
+   * @return a list of ranges.
    */
   public static List<Range> splitRanges(byte[] source, byte[] separator,
       int limit) {
@@ -132,7 +139,7 @@ public class TimelineStorageUtils {
         // everything else goes in one final segment
         break;
       }
-	      segments.add(new Range(start, i));
+      segments.add(new Range(start, i));
       start = i + separator.length;
       // i will be incremented again in outer for loop
       i += separator.length - 1;
@@ -219,9 +226,9 @@ public class TimelineStorageUtils {
 
   /**
    * returns the timestamp of that day's start (which is midnight 00:00:00 AM)
-   * for a given input timestamp
+   * for a given input timestamp.
    *
-   * @param ts
+   * @param ts Timestamp.
    * @return timestamp of that day's beginning (midnight)
    */
   public static long getTopOfTheDayTimestamp(long ts) {
@@ -233,9 +240,9 @@ public class TimelineStorageUtils {
    * Combines the input array of attributes and the input aggregation operation
    * into a new array of attributes.
    *
-   * @param attributes
-   * @param aggOp
-   * @return array of combined attributes
+   * @param attributes Attributes to be combined.
+   * @param aggOp Aggregation operation.
+   * @return array of combined attributes.
    */
   public static Attribute[] combineAttributes(Attribute[] attributes,
       AggregationOperation aggOp) {
@@ -257,8 +264,8 @@ public class TimelineStorageUtils {
    * Returns a number for the new array size. The new array is the combination
    * of input array of attributes and the input aggregation operation.
    *
-   * @param attributes
-   * @param aggOp
+   * @param attributes Attributes.
+   * @param aggOp Aggregation operation.
    * @return the size for the new array
    */
   private static int getNewLengthCombinedAttributes(Attribute[] attributes,
@@ -283,16 +290,17 @@ public class TimelineStorageUtils {
   }
 
   /**
-   * checks if an application has finished
+   * checks if an application has finished.
    *
-   * @param te
+   * @param te TimlineEntity object.
    * @return true if application has finished else false
    */
   public static boolean isApplicationFinished(TimelineEntity te) {
     SortedSet<TimelineEvent> allEvents = te.getEvents();
     if ((allEvents != null) && (allEvents.size() > 0)) {
       TimelineEvent event = allEvents.last();
-      if (event.getId().equals(ApplicationMetricsConstants.FINISHED_EVENT_TYPE)) {
+      if (event.getId().equals(
+          ApplicationMetricsConstants.FINISHED_EVENT_TYPE)) {
         return true;
       }
     }
@@ -300,26 +308,27 @@ public class TimelineStorageUtils {
   }
 
   /**
-   * get the time at which an app finished
+   * get the time at which an app finished.
    *
-   * @param te
+   * @param te TimelineEntity object.
    * @return true if application has finished else false
    */
   public static long getApplicationFinishedTime(TimelineEntity te) {
     SortedSet<TimelineEvent> allEvents = te.getEvents();
     if ((allEvents != null) && (allEvents.size() > 0)) {
       TimelineEvent event = allEvents.last();
-      if (event.getId().equals(ApplicationMetricsConstants.FINISHED_EVENT_TYPE)) {
+      if (event.getId().equals(
+          ApplicationMetricsConstants.FINISHED_EVENT_TYPE)) {
         return event.getTimestamp();
       }
     }
-    return 0l;
+    return 0L;
   }
 
   /**
    * Checks if the input TimelineEntity object is an ApplicationEntity.
    *
-   * @param te
+   * @param te TimelineEntity object.
    * @return true if input is an ApplicationEntity, false otherwise
    */
   public static boolean isApplicationEntity(TimelineEntity te) {
@@ -329,7 +338,7 @@ public class TimelineStorageUtils {
   /**
    * Checks for the APPLICATION_CREATED event.
    *
-   * @param te
+   * @param te TimelineEntity object.
    * @return true is application event exists, false otherwise
    */
   public static boolean isApplicationCreated(TimelineEntity te) {
@@ -346,9 +355,9 @@ public class TimelineStorageUtils {
 
   /**
    * Returns the first seen aggregation operation as seen in the list of input
-   * tags or null otherwise
+   * tags or null otherwise.
    *
-   * @param tags
+   * @param tags list of HBase tags.
    * @return AggregationOperation
    */
   public static AggregationOperation getAggregationOperationFromTagsList(
@@ -366,8 +375,8 @@ public class TimelineStorageUtils {
   /**
    * Creates a {@link Tag} from the input attribute.
    *
-   * @param attribute
-   * @return Tag
+   * @param attribute Attribute from which tag has to be fetched.
+   * @return a HBase Tag.
    */
   public static Tag getTagFromAttribute(Entry<String, byte[]> attribute) {
     // attribute could be either an Aggregation Operation or
@@ -380,8 +389,9 @@ public class TimelineStorageUtils {
       return t;
     }
 
-    AggregationCompactionDimension aggCompactDim = AggregationCompactionDimension
-        .getAggregationCompactionDimension(attribute.getKey());
+    AggregationCompactionDimension aggCompactDim =
+        AggregationCompactionDimension.getAggregationCompactionDimension(
+            attribute.getKey());
     if (aggCompactDim != null) {
       Tag t = new Tag(aggCompactDim.getTagType(), attribute.getValue());
       return t;
@@ -475,7 +485,8 @@ public class TimelineStorageUtils {
 
   /**
    * Checks if passed object is of integral type(Short/Integer/Long).
-   * @param obj
+   *
+   * @param obj Object to be checked.
    * @return true if object passed is of type Short or Integer or Long, false
    * otherwise.
    */

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/TimestampGenerator.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/TimestampGenerator.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/TimestampGenerator.java
index 555b64e..7238efa 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/TimestampGenerator.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/TimestampGenerator.java
@@ -40,6 +40,8 @@ public class TimestampGenerator {
   /**
    * Returns the current wall clock time in milliseconds, multiplied by the
    * required precision.
+   *
+   * @return current timestamp.
    */
   public long currentTime() {
     // We want to align cell timestamps with current time.
@@ -58,6 +60,8 @@ public class TimestampGenerator {
    * sustained rate of more than 1M hbase writes per second AND if region fails
    * over within that time range of timestamps being generated then there may be
    * collisions writing to a cell version of the same column.
+   *
+   * @return unique timestamp.
    */
   public long getUniqueTimestamp() {
     long lastTs;
@@ -78,8 +82,8 @@ public class TimestampGenerator {
    * column at the same time, then say appId of 1001 will overlap with appId of
    * 001 and there may be collisions for that flow run's specific column.
    *
-   * @param incomingTS
-   * @param appId
+   * @param incomingTS Timestamp to be converted.
+   * @param appId Application Id.
    * @return a timestamp multiplied with TS_MULTIPLIER and last few digits of
    *         application id
    */
@@ -101,9 +105,9 @@ public class TimestampGenerator {
 
   /**
    * truncates the last few digits of the timestamp which were supplemented by
-   * the TimestampGenerator#getSupplementedTimestamp function
+   * the TimestampGenerator#getSupplementedTimestamp function.
    *
-   * @param incomingTS
+   * @param incomingTS Timestamp to be truncated.
    * @return a truncated timestamp value
    */
   public static long getTruncatedTimestamp(long incomingTS) {

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ValueConverter.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ValueConverter.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ValueConverter.java
index 2388ba5..757a6d3 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ValueConverter.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/common/ValueConverter.java
@@ -28,18 +28,20 @@ public interface ValueConverter {
 
   /**
    * Encode an object as a byte array depending on the converter implementation.
-   * @param value
+   *
+   * @param value Value to be encoded.
    * @return a byte array
-   * @throws IOException
+   * @throws IOException if any problem is encountered while encoding.
    */
   byte[] encodeValue(Object value) throws IOException;
 
   /**
    * Decode a byte array and convert it into an object depending on the
    * converter implementation.
-   * @param bytes
+   *
+   * @param bytes Byte array to be decoded.
    * @return an object
-   * @throws IOException
+   * @throws IOException if any problem is encountered while decoding.
    */
   Object decodeValue(byte[] bytes) throws IOException;
 }

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityColumn.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityColumn.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityColumn.java
index deb8bd5..f47ba93 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityColumn.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityColumn.java
@@ -39,7 +39,7 @@ public enum EntityColumn implements Column<EntityTable> {
   ID(EntityColumnFamily.INFO, "id"),
 
   /**
-   * The type of entity
+   * The type of entity.
    */
   TYPE(EntityColumnFamily.INFO, "type"),
 

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityColumnPrefix.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityColumnPrefix.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityColumnPrefix.java
index 5b71228..f3c7e7f 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityColumnPrefix.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityColumnPrefix.java
@@ -54,7 +54,7 @@ public enum EntityColumnPrefix implements ColumnPrefix<EntityTable> {
   INFO(EntityColumnFamily.INFO, "i"),
 
   /**
-   * Lifecycle events for an entity
+   * Lifecycle events for an entity.
    */
   EVENT(EntityColumnFamily.INFO, "e"),
 
@@ -215,7 +215,8 @@ public enum EntityColumnPrefix implements ColumnPrefix<EntityTable> {
    *         is to facilitate returning byte arrays of values that were not
    *         Strings. If they can be treated as Strings, you should use
    *         {@link #readResults(Result)} instead.
-   * @throws IOException
+   * @throws IOException if there is any exception encountered while reading
+   *     result.
    */
   public Map<?, Object> readResultsHavingCompoundColumnQualifiers(Result result)
           throws IOException {
@@ -277,8 +278,8 @@ public enum EntityColumnPrefix implements ColumnPrefix<EntityTable> {
     for (EntityColumnPrefix ecp : EntityColumnPrefix.values()) {
       // Find a match based column family and on name.
       if (ecp.columnFamily.equals(columnFamily)
-          && (((columnPrefix == null) && (ecp.getColumnPrefix() == null)) || (ecp
-              .getColumnPrefix().equals(columnPrefix)))) {
+          && (((columnPrefix == null) && (ecp.getColumnPrefix() == null)) ||
+          (ecp.getColumnPrefix().equals(columnPrefix)))) {
         return ecp;
       }
     }

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityRowKey.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityRowKey.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityRowKey.java
index 3eaa78c..04c633c 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityRowKey.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityRowKey.java
@@ -74,14 +74,14 @@ public class EntityRowKey {
 
   /**
    * Constructs a row key prefix for the entity table as follows:
-   * {@code userName!clusterId!flowName!flowRunId!AppId}
+   * {@code userName!clusterId!flowName!flowRunId!AppId}.
    *
-   * @param clusterId
-   * @param userId
-   * @param flowName
-   * @param flowRunId
-   * @param appId
-   * @return byte array with the row key prefix
+   * @param clusterId Context cluster id.
+   * @param userId User name.
+   * @param flowName Flow name.
+   * @param flowRunId Run Id for the flow.
+   * @param appId Application Id.
+   * @return byte array with the row key prefix.
    */
   public static byte[] getRowKeyPrefix(String clusterId, String userId,
       String flowName, Long flowRunId, String appId) {
@@ -97,15 +97,17 @@ public class EntityRowKey {
 
   /**
    * Constructs a row key prefix for the entity table as follows:
-   * {@code userName!clusterId!flowName!flowRunId!AppId!entityType!}
+   * {@code userName!clusterId!flowName!flowRunId!AppId!entityType!}.
+   * Typically used while querying multiple entities of a particular entity
+   * type.
    *
-   * @param clusterId
-   * @param userId
-   * @param flowName
-   * @param flowRunId
-   * @param appId
-   * @param entityType
-   * @return byte array with the row key prefix
+   * @param clusterId Context cluster id.
+   * @param userId User name.
+   * @param flowName Flow name.
+   * @param flowRunId Run Id for the flow.
+   * @param appId Application Id.
+   * @param entityType Entity type.
+   * @return byte array with the row key prefix.
    */
   public static byte[] getRowKeyPrefix(String clusterId, String userId,
       String flowName, Long flowRunId, String appId, String entityType) {
@@ -123,16 +125,17 @@ public class EntityRowKey {
 
   /**
    * Constructs a row key for the entity table as follows:
-   * {@code userName!clusterId!flowName!flowRunId!AppId!entityType!entityId}
+   * {@code userName!clusterId!flowName!flowRunId!AppId!entityType!entityId}.
+   * Typically used while querying a specific entity.
    *
-   * @param clusterId
-   * @param userId
-   * @param flowName
-   * @param flowRunId
-   * @param appId
-   * @param entityType
-   * @param entityId
-   * @return byte array with the row key
+   * @param clusterId Context cluster id.
+   * @param userId User name.
+   * @param flowName Flow name.
+   * @param flowRunId Run Id for the flow.
+   * @param appId Application Id.
+   * @param entityType Entity type.
+   * @param entityId Entity Id.
+   * @return byte array with the row key.
    */
   public static byte[] getRowKey(String clusterId, String userId,
       String flowName, Long flowRunId, String appId, String entityType,
@@ -151,6 +154,9 @@ public class EntityRowKey {
 
   /**
    * Given the raw row key as bytes, returns the row key as an object.
+   *
+   * @param rowKey byte representation of row key.
+   * @return An <cite>EntityRowKey</cite> object.
    */
   public static EntityRowKey parseRowKey(byte[] rowKey) {
     byte[][] rowKeyComponents = Separator.QUALIFIERS.split(rowKey);

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityTable.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityTable.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityTable.java
index d7d770b..3e3e3ab 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityTable.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/EntityTable.java
@@ -69,27 +69,27 @@ import org.apache.hadoop.yarn.server.timelineservice.storage.common.TimelineHBas
  * </pre>
  */
 public class EntityTable extends BaseTable<EntityTable> {
-  /** entity prefix */
+  /** entity prefix. */
   private static final String PREFIX =
       YarnConfiguration.TIMELINE_SERVICE_PREFIX + "entity";
 
-  /** config param name that specifies the entity table name */
+  /** config param name that specifies the entity table name. */
   public static final String TABLE_NAME_CONF_NAME = PREFIX + ".table.name";
 
   /**
    * config param name that specifies the TTL for metrics column family in
-   * entity table
+   * entity table.
    */
   private static final String METRICS_TTL_CONF_NAME = PREFIX
       + ".table.metrics.ttl";
 
-  /** default value for entity table name */
+  /** default value for entity table name. */
   private static final String DEFAULT_TABLE_NAME = "timelineservice.entity";
 
-  /** default TTL is 30 days for metrics timeseries */
+  /** default TTL is 30 days for metrics timeseries. */
   private static final int DEFAULT_METRICS_TTL = 2592000;
 
-  /** default max number of versions */
+  /** default max number of versions. */
   private static final int DEFAULT_METRICS_MAX_VERSIONS = 1000;
 
   private static final Log LOG = LogFactory.getLog(EntityTable.class);
@@ -139,8 +139,8 @@ public class EntityTable extends BaseTable<EntityTable> {
     metricsCF.setMaxVersions(DEFAULT_METRICS_MAX_VERSIONS);
     metricsCF.setTimeToLive(hbaseConf.getInt(METRICS_TTL_CONF_NAME,
         DEFAULT_METRICS_TTL));
-    entityTableDescp
-        .setRegionSplitPolicyClassName("org.apache.hadoop.hbase.regionserver.KeyPrefixRegionSplitPolicy");
+    entityTableDescp.setRegionSplitPolicyClassName(
+        "org.apache.hadoop.hbase.regionserver.KeyPrefixRegionSplitPolicy");
     entityTableDescp.setValue("KeyPrefixRegionSplitPolicy.prefix_length",
         TimelineHBaseSchemaConstants.USERNAME_SPLIT_KEY_PREFIX_LENGTH);
     admin.createTable(entityTableDescp,

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/package-info.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/package-info.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/package-info.java
index 26f1cc5..0e9578a 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/package-info.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/entity/package-info.java
@@ -16,6 +16,10 @@
  * limitations under the License.
  */
 
+/**
+ * Package org.apache.hadoop.yarn.server.timelineservice.storage.entity
+ * contains classes related to implementation for entity table.
+ */
 @InterfaceAudience.Private
 @InterfaceStability.Unstable
 package org.apache.hadoop.yarn.server.timelineservice.storage.entity;

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/AggregationCompactionDimension.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/AggregationCompactionDimension.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/AggregationCompactionDimension.java
index ff12c7b..4e2cf2d 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/AggregationCompactionDimension.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/AggregationCompactionDimension.java
@@ -26,7 +26,7 @@ import org.apache.hadoop.hbase.util.Bytes;
 public enum AggregationCompactionDimension {
 
   /**
-   * the application id
+   * the application id.
    */
   APPLICATION_ID((byte) 101);
 
@@ -50,8 +50,8 @@ public enum AggregationCompactionDimension {
     return this.inBytes.clone();
   }
 
-  public static AggregationCompactionDimension getAggregationCompactionDimension(
-      String aggCompactDimStr) {
+  public static AggregationCompactionDimension
+      getAggregationCompactionDimension(String aggCompactDimStr) {
     for (AggregationCompactionDimension aggDim : AggregationCompactionDimension
         .values()) {
       if (aggDim.name().equals(aggCompactDimStr)) {

http://git-wip-us.apache.org/repos/asf/hadoop/blob/db76a3ad/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/AggregationOperation.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/AggregationOperation.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/AggregationOperation.java
index c635ce6..6240e81 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/AggregationOperation.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/AggregationOperation.java
@@ -36,17 +36,17 @@ public enum AggregationOperation {
   MAX((byte) 73),
 
   /**
-   * The metrics of the flow
+   * The metrics of the flow.
    */
   SUM((byte) 79),
 
   /**
-   * application running
+   * application running.
    */
   SUM_FINAL((byte) 83),
 
   /**
-   * compact
+   * compact.
    */
   COMPACT((byte) 89);
 
@@ -71,8 +71,8 @@ public enum AggregationOperation {
   }
 
   /**
-   * returns the AggregationOperation enum that represents that string
-   * @param aggOpStr
+   * returns the AggregationOperation enum that represents that string.
+   * @param aggOpStr Aggregation operation.
    * @return the AggregationOperation enum that represents that string
    */
   public static AggregationOperation getAggregationOperation(String aggOpStr) {