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* 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
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package org.apache.cayenne.access.translator.ejbql;
import org.apache.cayenne.ejbql.EJBQLBaseVisitor;
import org.apache.cayenne.ejbql.EJBQLExpression;
import org.apache.cayenne.ejbql.parser.EJBQLFromItem;
import org.apache.cayenne.ejbql.parser.EJBQLInnerFetchJoin;
import org.apache.cayenne.ejbql.parser.EJBQLJoin;
import org.apache.cayenne.ejbql.parser.EJBQLOuterFetchJoin;
/**
* @since 3.0
*/
public class EJBQLFromTranslator extends EJBQLBaseVisitor {
protected EJBQLTranslationContext context;
private String lastId;
private EJBQLJoinAppender joinAppender;
public EJBQLFromTranslator(EJBQLTranslationContext context) {
super(true);
this.context = context;
this.joinAppender = context.getTranslatorFactory().getJoinAppender(context);
}
@Override
public boolean visitFrom(EJBQLExpression expression, int finishedChildIndex) {
if (finishedChildIndex + 1 == expression.getChildrenCount()) {
if (lastId != null) {
context.markCurrentPosition(EJBQLJoinAppender.makeJoinTailMarker(lastId));
}
}
return true;
}
@Override
public boolean visitFromItem(EJBQLFromItem expression, int finishedChildIndex) {
String id = expression.getId();
if (lastId != null) {
context.append(',');
context.markCurrentPosition(EJBQLJoinAppender.makeJoinTailMarker(lastId));
}
this.lastId = id;
joinAppender.appendTable(new EJBQLTableId(id));
return false;
}
@Override
public boolean visitInnerFetchJoin(EJBQLJoin join) {
joinAppender.appendInnerJoin(
null,
new EJBQLTableId(join.getLeftHandSideId()),
new EJBQLTableId(((EJBQLInnerFetchJoin) join).getRightHandSideId()));
context.markCurrentPosition(EJBQLJoinAppender
.makeJoinTailMarker(((EJBQLInnerFetchJoin) join).getRightHandSideId()));
return false;
}
@Override
public boolean visitInnerJoin(EJBQLJoin join) {
joinAppender.appendInnerJoin(
null,
new EJBQLTableId(join.getLeftHandSideId()),
new EJBQLTableId(join.getRightHandSideId()));
//fix 1341-mark current join position for probable future joins to this join
context.markCurrentPosition(EJBQLJoinAppender.makeJoinTailMarker(join.getRightHandSideId()));
return false;
}
@Override
public boolean visitOuterFetchJoin(EJBQLJoin join) {
joinAppender.appendOuterJoin(
null,
new EJBQLTableId(join.getLeftHandSideId()),
new EJBQLTableId(((EJBQLOuterFetchJoin) join).getRightHandSideId()));
context.markCurrentPosition(EJBQLJoinAppender
.makeJoinTailMarker(((EJBQLOuterFetchJoin) join).getRightHandSideId()));
return false;
}
@Override
public boolean visitOuterJoin(EJBQLJoin join) {
joinAppender.appendOuterJoin(
null,
new EJBQLTableId(join.getLeftHandSideId()),
new EJBQLTableId(join.getRightHandSideId()));
context.markCurrentPosition(EJBQLJoinAppender.makeJoinTailMarker(join.getRightHandSideId()));
return false;
}
}