SymbolExpression.java

package com.cheng.zenofdesignpatterns.patterns.interpreter.calculator;

/**
 * 抽象运算符号解析器
 */
public abstract class SymbolExpression extends Expression {

    protected Expression left;
    protected Expression right;

    // 所有的解析公式都应只关心自己左右两个表达式的结果
    public SymbolExpression(Expression _left, Expression _right) {
        this.left = _left;
        this.right = _right;
    }
}