/*
* Copyright 1999-2012 Alibaba Group.
*
* 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.
*/
/**
* (created at 2011-1-12)
*/
package com.alibaba.cobar.parser.ast.expression.logical;
import java.util.Map;
import com.alibaba.cobar.parser.ast.expression.BinaryOperatorExpression;
import com.alibaba.cobar.parser.ast.expression.Expression;
import com.alibaba.cobar.parser.ast.expression.primary.literal.LiteralBoolean;
import com.alibaba.cobar.parser.util.ExprEvalUtils;
import com.alibaba.cobar.parser.visitor.SQLASTVisitor;
/**
* @author <a href="mailto:shuo.qius@alibaba-inc.com">QIU Shuo</a>
*/
public class LogicalXORExpression extends BinaryOperatorExpression {
public LogicalXORExpression(Expression left, Expression right){
super(left, right, PRECEDENCE_LOGICAL_XOR);
}
@Override
public String getOperator() {
return "XOR";
}
@Override
public Object evaluationInternal(Map<? extends Object, ? extends Object> parameters) {
Object left = leftOprand.evaluation(parameters);
Object right = rightOprand.evaluation(parameters);
if (left == null || right == null) return null;
if (left == UNEVALUATABLE || right == UNEVALUATABLE) return UNEVALUATABLE;
boolean b1 = ExprEvalUtils.obj2bool(left);
boolean b2 = ExprEvalUtils.obj2bool(right);
return b1 != b2 ? LiteralBoolean.TRUE : LiteralBoolean.FALSE;
}
@Override
public void accept(SQLASTVisitor visitor) {
visitor.visit(this);
}
}