org.apache.openjpa.kernel.exps.ContainsExpression Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
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* KIND, either express or implied. See the License for the
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*/
package org.apache.openjpa.kernel.exps;
import java.util.Collection;
import java.util.Collections;
import org.apache.openjpa.kernel.StoreContext;
/**
* Tests that a Collection contains a value.
*
* @author Abe White
*/
class ContainsExpression
extends Exp {
private final Val _val1;
private final Val _val2;
/**
* Constructor.
*
* @param val1 the container value
* @param val2 the containee to test
*/
public ContainsExpression(Val val1, Val val2) {
_val1 = val1;
_val2 = val2;
}
protected boolean eval(Object candidate, Object orig,
StoreContext ctx, Object[] params) {
Object obj = _val1.eval(candidate, orig, ctx, params);
Collection coll = getCollection(obj);
return coll != null && !coll.isEmpty()
&& coll.contains(_val2.eval(candidate, orig, ctx, params));
}
protected boolean eval(Collection candidates, StoreContext ctx,
Object[] params) {
Collection coll = _val1.eval(candidates, null, ctx, params);
if (coll == null || coll.isEmpty())
return false;
coll = getCollection(coll.iterator().next());
if (coll == null || coll.isEmpty())
return false;
Collection coll2 = _val2.eval(candidates, null, ctx, params);
if (coll2 == null || coll2.isEmpty())
return false;
return coll.contains(coll2.iterator().next());
}
/**
* Return the container collection for the given value.
*/
protected Collection getCollection(Object obj) {
return obj instanceof Collection ?
(Collection) obj : Collections.singleton(obj);
}
public void acceptVisit(ExpressionVisitor visitor) {
visitor.enter(this);
_val1.acceptVisit(visitor);
_val2.acceptVisit(visitor);
visitor.exit(this);
}
}