com.blazebit.persistence.impl.JoinNodeGathererVisitor Maven / Gradle / Ivy
/*
* Copyright 2014 - 2020 Blazebit.
*
* Licensed 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 com.blazebit.persistence.impl;
import com.blazebit.persistence.parser.expression.PathExpression;
import com.blazebit.persistence.parser.expression.VisitorAdapter;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
/**
*
* @author Christian Beikov
* @since 1.3.0
*/
public class JoinNodeGathererVisitor extends VisitorAdapter {
private Collection joinNodes;
public JoinNodeGathererVisitor() {
}
public JoinNodeGathererVisitor(Collection joinNodes) {
this.joinNodes = joinNodes;
}
public Set collectNonRootJoinNodes(ResolvedExpression[] identifierExpressions) {
joinNodes = new ArrayList<>();
int size = identifierExpressions.length;
for (int i = 0; i < size; i++) {
identifierExpressions[i].getExpression().accept(this);
}
Set nonRootJoinNodeClosure = new HashSet<>();
List nodes = (List) joinNodes;
size = nodes.size();
for (int i = 0; i < size; i++) {
JoinNode n = nodes.get(i);
if (n.getParent() != null) {
nonRootJoinNodeClosure.add(n);
nonRootJoinNodeClosure.addAll(n.getDependencies());
}
}
return nonRootJoinNodeClosure;
}
@Override
public void visit(PathExpression expression) {
joinNodes.add((JoinNode) expression.getBaseNode());
}
}