jsp中利用javabean

来源：互联网发布：centos iso 本地yum 编辑：程序博客网时间：2024/05/16 08:18

用一个简单计算功能的javabean嵌入到jsp中去。javabean的代码如下：

package com.shizhan;public class Computer {private double shu1;private double shu2;private String operate;public Computer() {}public Computer(double shu1, double shu2, String operate) {super();this.shu1 = shu1;this.shu2 = shu2;this.operate = operate;}public double getShu1() {return shu1;}public void setShu1(double shu1) {this.shu1 = shu1;}public double getShu2() {return shu2;}public void setShu2(double shu2) {this.shu2 = shu2;}public String getOperate() {return operate;}public void setOperate(String operate) {this.operate = operate;}public double computer(){if(operate.equals("+")){return shu1+shu2;}if(operate.equals("-")){return shu1-shu2;}if(operate.equals("*")){return shu1*shu2;}if(operate.equals("/")){return shu1/shu2;}return 0;}}

jsp的代码如下：

<%@ page language="java" import="java.util.*" pageEncoding="gb2312"%><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%><html>  <head>    <base href="<%=basePath%>">  </head>    <body>   <jsp:useBean id="computer" class="com.shizhan.Computer"></jsp:useBean>   <form action="" method="post">                    操作数1<input type="text" name="shu1"/><BR>        <select name="operate">           <option  value="+">+</option>           <option  value="-">-</option>           <option  value="*">*</option>           <option  value="/">/</option>        </select>                            操作数2<input type="text" name="shu2"/>          <input type="submit" name="avas" value="计算">    </form>      <jsp:setProperty property="*" name="computer"/>    <%       double res;       if(request.getParameter("shu1")!=null && request.getParameter("shu2")!=null)       {          res=computer.computer();    %>           结果<input type="text" name="res" value=           <%=res%>           ><BR>      <%       }       else       {    %>         结果<input type="text" name="res" ><BR>      <%       }    %>   </body></html>