/**
*
* Copyright 2014 The Darks ORM Project (Liu lihua)
*
* 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 darks.orm.core.data.tags.express.impl;
import java.util.LinkedList;
import darks.orm.core.data.tags.express.ExpressException;
import darks.orm.core.data.tags.express.RPNOper;
/**
* �����������
* @author lihua.llh
*
*/
public abstract class LogicOper implements RPNOper
{
private String name;
public LogicOper(String name)
{
this.name = name;
}
/**
* {@inheritDoc}
*/
@Override
public void compute(LinkedList<Object> stack, Object param) throws ExpressException
{
if (stack.size() < 2)
{
throw new ExpressException(name + " oper Need two values. Which only has " + stack);
}
Object val2 = (Object) stack.pop();
Object val1 = (Object) stack.pop();
Object result = null;
if ((val1 instanceof Boolean) && (val2 instanceof Boolean))
{
result = compute((Boolean) val1, (Boolean) val2);
stack.push(result);
}
else
{
throw new ExpressException("Invalid data type when compute RPN express."
+ val1 + " " + name + " " + val2);
}
}
/**
* �Բ�����������������
* @param val1 Դ������
* @param val2 Ŀ�������
* @return ������
*/
public abstract Object compute(Boolean src, Boolean desc);
}