/*
* 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 2011-1-14)
*/
package com.alibaba.cobar.parser.ast.expression;
import java.util.Map;
import com.alibaba.cobar.parser.visitor.SQLASTVisitor;
/**
* @author <a href="mailto:shuo.qius@alibaba-inc.com">QIU Shuo</a>
*/
public abstract class UnaryOperatorExpression extends AbstractExpression {
private final Expression operand;
protected final int precedence;
public UnaryOperatorExpression(Expression operand, int precedence) {
if (operand == null)
throw new IllegalArgumentException("operand is null");
this.operand = operand;
this.precedence = precedence;
}
public Expression getOperand() {
return operand;
}
@Override
public int getPrecedence() {
return precedence;
}
public abstract String getOperator();
@Override
public Object evaluationInternal(Map<? extends Object, ? extends Object> parameters) {
return UNEVALUATABLE;
}
@Override
public void accept(SQLASTVisitor visitor) {
visitor.visit(this);
}
}