org.apache.openjpa.kernel.exps.UnaryMathVal 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 org.apache.openjpa.kernel.StoreContext;
/**
* Value produced by a mathematical operation on one value.
*
* @author Abe White
*/
abstract class UnaryMathVal
extends Val {
private final Val _val;
/**
* Constructor. Provide the value to operate on.
*/
public UnaryMathVal(Val val) {
_val = val;
}
public Class getType() {
return getType(_val.getType());
}
public void setImplicitType(Class type) {
}
protected Object eval(Object candidate, Object orig,
StoreContext ctx, Object[] params) {
Object o1 = _val.eval(candidate, orig, ctx, params);
return operate(o1, _val.getType());
}
/**
* Return the type of this value based on the numeric type being operated
* on.
*/
protected abstract Class getType(Class c);
/**
* Return the result of this mathematical operation on the given value.
*/
protected abstract Object operate(Object o, Class c);
public void acceptVisit(ExpressionVisitor visitor) {
visitor.enter(this);
_val.acceptVisit(visitor);
visitor.exit(this);
}
}