/**
 * 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 com.huawei.streaming.expression;

/**
 * 
 * <表达式运算枚举类>
 * 
 */
public enum ExpressionOperator
{
    //Arithmetic Expression Operator
    /**
     * 加
     */
    ADD("+"),
    
    /**
     * 减
     */
    SUBTRACT("-"),
    
    /**
     * 乘
     */
    MULTIPLY("*"),
    
    /**
     * 除
     */
    DIVIDE("/"),
    
    /**
     * 余
     */
    MOD("%"),
    
    //relation Expression Operator
    /**
     * 小于
     */
    LESSTHAN("<"),
    
    /**
     * 大于
     */
    GREATERTHAN(">"),
    
    /**
     * 小于或等于
     */
    LESSTHAN_EQUAL("<="),
    
    /**
     * 大于或等于
     */
    GREATERTHAN_EQUAL(">="),
    
    /**
     * 等于
     */
    EQUAL("="),
    
    /**
     * 不等于
     * 或者是<>
     */
    NOT_EQUAL("!="),
    
    //logic
    /**
     * 与
     */
    LOGICAND("and"),
    
    /**
     * 或
     */
    LOGICOR("or");
    
    /**
     * 表达式枚举类型的描述
     */
    private String desc;
    
    /**
     * <默认构造函数>
     */
    private ExpressionOperator(String desc)
    {
        this.desc = desc;
    }
    
    public String getDesc()
    {
        return desc;
    }
}
