constant.java

来自「java与模式随书源码,作者阎宏博士,包括书中各个设计模式的实现,没有密码,」· Java 代码 · 共 36 行

package com.javapatterns.interpreter;

public class Constant extends Expression
{
    private boolean value;

    public Constant(boolean value)
    {
		this.value = value;
    }

    public boolean interpret(Context ctx)
    {
		return value;
    }

    public boolean equals(Object o)
    {
        if (o != null && o instanceof Constant)
        {
          return this.value == ((Constant) o).value;
        }
        return false;
    }

    public int hashCode()
    {
        return (this.toString()).hashCode();
    }

    public String toString()
    {
		return new Boolean(value).toString();
    }
}