org.apache.openjpa.kernel.exps.Exp Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* 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
* "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 org.apache.openjpa.kernel.exps;
import java.util.Collection;
import org.apache.openjpa.kernel.StoreContext;
/**
* An in-memory representation of an {@link Expression}.
*
* @author Abe White
*/
public class Exp
implements Expression {
/**
* Evaluate the expression for the given candidate.
*/
public final boolean evaluate(Object candidate, Object orig,
StoreContext ctx, Object[] params) {
try {
return eval(candidate, candidate, ctx, params);
} catch (ClassCastException cce) {
return false;
} catch (NullPointerException npe) {
return false;
}
}
/**
* Evaluate the expression for the given candidate group.
*/
public final boolean evaluate(Collection candidates,
StoreContext ctx, Object[] params) {
try {
return eval(candidates, ctx, params);
} catch (ClassCastException cce) {
return false;
} catch (NullPointerException npe) {
return false;
}
}
/**
* Evaluate the expression for the given context candidate and original
* candidate.
*/
protected boolean eval(Object candidate, Object orig,
StoreContext ctx, Object[] params) {
return true;
}
/**
* Evaluate the expression for the given group.
*/
protected boolean eval(Collection candidates, StoreContext ctx,
Object[] params) {
return true;
}
public void acceptVisit(ExpressionVisitor visitor) {
visitor.enter(this);
visitor.exit(this);
}
}