oracle.toplink.essentials.internal.parsing.SubqueryNode Maven / Gradle / Ivy
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* of the Common Development and Distribution License
* (the "License"). You may not use this file except
* in compliance with the License.
*
* You can obtain a copy of the license at
* glassfish/bootstrap/legal/CDDLv1.0.txt or
* https://glassfish.dev.java.net/public/CDDLv1.0.html.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* HEADER in each file and include the License file at
* glassfish/bootstrap/legal/CDDLv1.0.txt. If applicable,
* add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your
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// Copyright (c) 1998, 2007, Oracle. All rights reserved.
package oracle.toplink.essentials.internal.parsing;
import java.util.Set;
import oracle.toplink.essentials.expressions.*;
import oracle.toplink.essentials.queryframework.ReportQuery;
/**
* INTERNAL
* Purpose: Represent a subquery.
*/
public class SubqueryNode extends Node {
private EJBQLParseTree subqueryParseTree;
/** Set of names of variables declared in an outer scope and used in teh
* subquery. */
private Set outerVars;
/**
* Return a new SubqueryNode.
*/
public SubqueryNode() {
super();
}
/** */
public ReportQuery getReportQuery(GenerationContext context) {
ReportQuery innerQuery = new ReportQuery();
GenerationContext innerContext =
subqueryParseTree.populateSubquery(innerQuery, context);
Expression joins = innerContext.joinVariables(outerVars);
if (joins != null) {
Expression where = innerQuery.getSelectionCriteria();
where = appendExpression(where, joins);
innerQuery.setSelectionCriteria(where);
}
return innerQuery;
}
/**
* INTERNAL
* If called the subquery is part of the WHERE clause of an UPDATE or
* DELETE statement that does not define an identification variable.
* The method checks the clauses of the subquery for unqualified fields
* accesses.
*/
public Node qualifyAttributeAccess(ParseTreeContext context) {
subqueryParseTree.getFromNode().qualifyAttributeAccess(context);
subqueryParseTree.getQueryNode().qualifyAttributeAccess(context);
if (subqueryParseTree.getWhereNode() != null) {
subqueryParseTree.getWhereNode().qualifyAttributeAccess(context);
}
if (subqueryParseTree.getGroupByNode() != null) {
subqueryParseTree.getGroupByNode().qualifyAttributeAccess(context);
}
if (subqueryParseTree.getHavingNode() != null) {
subqueryParseTree.getHavingNode().qualifyAttributeAccess(context);
}
return this;
}
/**
* INTERNAL
* Validate node and calculate its type.
*/
public void validate(ParseTreeContext context) {
subqueryParseTree.validate(context);
outerVars = context.getOuterScopeVariables();
SelectNode selectNode = (SelectNode)subqueryParseTree.getQueryNode();
// Get the select expression, subqueries only have one
Node selectExpr = (Node)selectNode.getSelectExpressions().get(0);
setType(selectExpr.getType());
}
/**
* INTERNAL
* Generate the TopLink expression for this node
*/
public Expression generateExpression(GenerationContext context) {
Expression base = context.getBaseExpression();
ReportQuery innerQuery = getReportQuery(context);
return base.subQuery(innerQuery);
}
/**
* INTERNAL
* Is this node a SubqueryNode
*/
public boolean isSubqueryNode() {
return true;
}
/** */
public void setParseTree(EJBQLParseTree parseTree) {
this.subqueryParseTree = parseTree;
}
/** */
public EJBQLParseTree getParseTree() {
return subqueryParseTree;
}
}