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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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* KIND, either express or implied. See the License for the
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package org.apache.cayenne.exp.parser;
import org.apache.cayenne.exp.Expression;
import org.apache.commons.collections.Transformer;
/**
* "In" expression.
*
*/
public class ASTIn extends ConditionNode {
private static final long serialVersionUID = -211084571117172965L;
/**
* Constructor used by expression parser. Do not invoke directly.
*/
ASTIn(int id) {
super(id);
}
public ASTIn() {
super(ExpressionParserTreeConstants.JJTIN);
}
public ASTIn(SimpleNode path, ASTList list) {
super(ExpressionParserTreeConstants.JJTIN);
jjtAddChild(path, 0);
jjtAddChild(list, 1);
connectChildren();
}
@Override
protected int getRequiredChildrenCount() {
return 2;
}
@Override
protected Boolean evaluateSubNode(Object o, Object[] evaluatedChildren) throws Exception {
if (o == null || evaluatedChildren[1] == null) {
// Even if there is NULL value in list we should return false,
// as check against NULL can be done only with IS NULL operator
// and moreover not all DB accept syntax like 'value IN (NULL)'
return Boolean.FALSE;
}
Object[] objects = (Object[]) evaluatedChildren[1];
for (Object object : objects) {
if (object != null && Evaluator.evaluator(o).eq(o, object)) {
return Boolean.TRUE;
}
}
return Boolean.FALSE;
}
/**
* Creates a copy of this expression node, without copying children.
*/
@Override
public Expression shallowCopy() {
return new ASTIn(id);
}
@Override
protected String getExpressionOperator(int index) {
return "in";
}
@Override
public int getType() {
return Expression.IN;
}
@Override
protected Object transformExpression(Transformer transformer) {
Object transformed = super.transformExpression(transformer);
// transform empty ASTIn to ASTFalse
if (transformed instanceof ASTIn) {
ASTIn exp = (ASTIn) transformed;
if (exp.jjtGetNumChildren() == 2) {
ASTList list = (ASTList) exp.jjtGetChild(1);
Object[] objects = (Object[]) list.evaluate(null);
if (objects.length == 0) {
transformed = new ASTFalse();
}
}
}
return transformed;
}
}