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Posted to commits@cayenne.apache.org by aa...@apache.org on 2008/05/06 12:55:05 UTC
svn commit: r653743 - in
/cayenne/main/trunk/framework/cayenne-jdk1.5-unpublished/src/main/java/org/apache/cayenne/access/trans:
JoinProcessor.java JoinTreeNode.java
Author: aadamchik
Date: Tue May 6 03:55:04 2008
New Revision: 653743
URL: http://svn.apache.org/viewvc?rev=653743&view=rev
Log:
CAY-802 Split Expressions
(standalone class for merging expressions into joins)
Added:
cayenne/main/trunk/framework/cayenne-jdk1.5-unpublished/src/main/java/org/apache/cayenne/access/trans/JoinProcessor.java
cayenne/main/trunk/framework/cayenne-jdk1.5-unpublished/src/main/java/org/apache/cayenne/access/trans/JoinTreeNode.java
Added: cayenne/main/trunk/framework/cayenne-jdk1.5-unpublished/src/main/java/org/apache/cayenne/access/trans/JoinProcessor.java
URL: http://svn.apache.org/viewvc/cayenne/main/trunk/framework/cayenne-jdk1.5-unpublished/src/main/java/org/apache/cayenne/access/trans/JoinProcessor.java?rev=653743&view=auto
==============================================================================
--- cayenne/main/trunk/framework/cayenne-jdk1.5-unpublished/src/main/java/org/apache/cayenne/access/trans/JoinProcessor.java (added)
+++ cayenne/main/trunk/framework/cayenne-jdk1.5-unpublished/src/main/java/org/apache/cayenne/access/trans/JoinProcessor.java Tue May 6 03:55:04 2008
@@ -0,0 +1,116 @@
+/*****************************************************************
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ ****************************************************************/
+package org.apache.cayenne.access.trans;
+
+import java.io.IOException;
+import java.util.List;
+
+import org.apache.cayenne.map.DbEntity;
+import org.apache.cayenne.map.DbJoin;
+import org.apache.cayenne.map.DbRelationship;
+import org.apache.cayenne.map.JoinType;
+
+/**
+ * Encapsulates join reuse/split logic used in SelectQuery processing. All expression
+ * path's that exist in the query (in the qualifier, etc.) are processed to produce a
+ * combined join tree.
+ *
+ * @since 3.0
+ * @author Andrus Adamchik
+ */
+class JoinProcessor {
+
+ private JoinTreeNode root;
+ private JoinTreeNode topNode;
+
+ JoinProcessor(SelectTranslator tableAliasSource) {
+ String rootAlias = tableAliasSource.aliasForTable(tableAliasSource
+ .getRootDbEntity());
+ this.root = new JoinTreeNode(tableAliasSource);
+ this.root.setTargetTableAlias(rootAlias);
+ resetStack();
+ }
+
+ /**
+ * Appends all configured joins to the provided output object.
+ */
+ void appendJoins(Appendable out) throws IOException {
+ appendJoinSubtree(out, root);
+ }
+
+ private void appendJoinSubtree(Appendable out, JoinTreeNode node) throws IOException {
+
+ DbRelationship relationship = node.getRelationship();
+
+ DbEntity targetEntity = (DbEntity) relationship.getTargetEntity();
+ String srcAlias = node.getSourceTableAlias();
+ String targetAlias = node.getTargetTableAlias();
+
+ switch (node.getJoinType()) {
+ case INNER:
+ out.append(" JOIN");
+ break;
+ case LEFT_OUTER:
+ out.append(" LEFT JOIN");
+ break;
+ default:
+ throw new IllegalArgumentException("Unsupported join type: "
+ + node.getJoinType());
+ }
+
+ out.append(' ').append(targetEntity.getFullyQualifiedName()).append(' ').append(
+ targetAlias).append(" ON (");
+
+ List<DbJoin> joins = relationship.getJoins();
+ int len = joins.size();
+ for (int i = 0; i < len; i++) {
+ DbJoin join = joins.get(i);
+
+ if (i > 0) {
+ out.append(" AND ");
+ }
+
+ out
+ .append(srcAlias)
+ .append('.')
+ .append(join.getSourceName())
+ .append(" = ")
+ .append(targetAlias)
+ .append('.')
+ .append(join.getTargetName());
+ }
+
+ out.append(')');
+ }
+
+ /**
+ * Pops the stack all the way to the root node.
+ */
+ void resetStack() {
+ topNode = root;
+ }
+
+ /**
+ * Finds or creates a JoinTreeNode for the given arguments and sets it as the next
+ * current join.
+ */
+ void pushJoin(DbRelationship relationship, JoinType joinType, String alias) {
+ topNode = topNode.findOrCreateChild(relationship, joinType, alias);
+ }
+}
Added: cayenne/main/trunk/framework/cayenne-jdk1.5-unpublished/src/main/java/org/apache/cayenne/access/trans/JoinTreeNode.java
URL: http://svn.apache.org/viewvc/cayenne/main/trunk/framework/cayenne-jdk1.5-unpublished/src/main/java/org/apache/cayenne/access/trans/JoinTreeNode.java?rev=653743&view=auto
==============================================================================
--- cayenne/main/trunk/framework/cayenne-jdk1.5-unpublished/src/main/java/org/apache/cayenne/access/trans/JoinTreeNode.java (added)
+++ cayenne/main/trunk/framework/cayenne-jdk1.5-unpublished/src/main/java/org/apache/cayenne/access/trans/JoinTreeNode.java Tue May 6 03:55:04 2008
@@ -0,0 +1,122 @@
+/*****************************************************************
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ ****************************************************************/
+package org.apache.cayenne.access.trans;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+
+import org.apache.cayenne.map.DbEntity;
+import org.apache.cayenne.map.DbRelationship;
+import org.apache.cayenne.map.JoinType;
+import org.apache.cayenne.util.Util;
+
+/**
+ * @since 3.0
+ * @author Andrus Adamchik
+ */
+final class JoinTreeNode {
+
+ private String targetTableAlias;
+ private String sourceTableAlias;
+ private DbRelationship relationship;
+ private String alias;
+ private JoinType joinType;
+ private Collection<JoinTreeNode> children;
+ private SelectTranslator tableAliasSource;
+
+ JoinTreeNode(SelectTranslator tableAliasSource) {
+ this.tableAliasSource = tableAliasSource;
+ }
+
+ JoinTreeNode(SelectTranslator tableAliasSource, DbRelationship relationship,
+ JoinType joinType, String alias) {
+ this(tableAliasSource);
+ this.relationship = relationship;
+ this.alias = alias;
+ this.joinType = joinType;
+ }
+
+ Collection<JoinTreeNode> getChildren() {
+ return children != null ? children : Collections.<JoinTreeNode> emptyList();
+ }
+
+ JoinTreeNode findOrCreateChild(
+ DbRelationship relationship,
+ JoinType joinType,
+ String alias) {
+
+ if (children == null) {
+ children = new ArrayList<JoinTreeNode>(4);
+ }
+ else {
+ for (JoinTreeNode child : children) {
+
+ if (child.equals(relationship, joinType, alias)) {
+ return child;
+ }
+ }
+ }
+
+ JoinTreeNode child = new JoinTreeNode(
+ tableAliasSource,
+ relationship,
+ joinType,
+ alias);
+ child.setSourceTableAlias(this.targetTableAlias);
+ child.setTargetTableAlias(tableAliasSource
+ .newAliasForTable((DbEntity) relationship.getTargetEntity()));
+ children.add(child);
+ return child;
+ }
+
+ private boolean equals(DbRelationship relationship, JoinType joinType, String alias) {
+ return this.relationship == relationship
+ && this.joinType == joinType
+ && Util.nullSafeEquals(this.alias, alias);
+ }
+
+ String getTargetTableAlias() {
+ return targetTableAlias;
+ }
+
+ void setTargetTableAlias(String targetTableAlias) {
+ this.targetTableAlias = targetTableAlias;
+ }
+
+ String getSourceTableAlias() {
+ return sourceTableAlias;
+ }
+
+ void setSourceTableAlias(String sourceTableAlias) {
+ this.sourceTableAlias = sourceTableAlias;
+ }
+
+ DbRelationship getRelationship() {
+ return relationship;
+ }
+
+ String getAlias() {
+ return alias;
+ }
+
+ JoinType getJoinType() {
+ return joinType;
+ }
+}
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