JSP与JavaBean

JSP动态网页设计之JSP与JavaBean。编程环境：Java 5.0.8+eclipse 3.2 + MyEclipse 5.0 + Tomcat 5.5.17

好，学完理论，下面编写代码：

打开eclipse，新建一个MyEclipse下面J2EE类的web项目，如图：

项目名为：JspJiLinCh06，今天所有代码的树型图如下：

新建一个com.coderdream.bean 包，然后新建一个SampleBean1类，代码如下：

1 package com.coderdream.bean;
2
3 public class SampleBean1 {
4
5     private String str;
6
7     public SampleBean1() {
8         // TODO 自动生成构造函数存根
9     }
10
11     public String getStr() {
12         return str;
13     }
14
15     public void setStr(String str) {
16         this.str = str;
17     }
18
19 }

然后再新建一个sample1.jsp页面，代码如下：

<%@ page language="java" contentType="text/html; charset=GB2312"%>
2

<jsp:useBean id="smBean" class="com.coderdream.bean.SampleBean1"></jsp:useBean>
3

<html>
4

<head>
5

<title>一个简单的JavaBean程序</title>
6

</head>
7

<body>
8

<center>
9

<%
10

smBean.setStr("这是我的第一个JavaBean程序！");
11

%>
12

<%=smBean.getStr()%>
13

</center>
14

</body>
15

</html>

将项目发布后，打开Tomcat 服务器，输入网址，结果为：

下面来看看如何使用的两个标记：分别建立SampleBean2类和两个页面文件sample2.html和sample2.jsp，代码如下：

SampleBean2.java

1 package com.coderdream.bean;
2
3 public class SampleBean2 {
4
5     private String id;
6     private String age;
7
8     public SampleBean2() {
9         // TODO 自动生成构造函数存根
10     }
11
12     public String getAge() {
13         return age;
14     }
15
16     public void setAge(String age) {
17         this.age = age;
18     }
19
20     public String getId() {
21         return id;
22     }
23
24     public void setId(String id) {
25         this.id = id;
26     }
27
28 }

sample2.html

<html>
2

<head>
3

<title>使用<jsp:Property&gt和<jsp:setProperty&gt标记</title>
4

</head>
6

<body>
8

<form name="form1" action="sample2.jsp" method="post">
9

<table align="center" border="0">
10

<tr>
11

<td>编号:</td>
12

<td><input type="text" name="id" ></td>
13

</tr>
14

<tr>
15

<td>年龄:</td>
16

<td><input type="text" name="age"></td>
17

</tr>
18

<tr>
19

<td><input type="submit" value="提交"></td>
20

<td><input type="reset" value="重填"></td>
21

</tr>
22

</table>
23

</form>
24

</body>
25

</html>
26

sample2.jsp

<%@ page language="java" contentType="text/html; charset=GB2312"%>
<jsp:useBean id="splBean" class="com.coderdream.bean.SampleBean2"></jsp:useBean>
<html>
    <head>
        <title>My JSP 'sample1.jsp' starting page</title>
    </head>
    <body>
        

        
        

        
        

        <jsp:setProperty name="splBean" property="id" value="${param.id}"/>
        <jsp:setProperty name="splBean" property="age" value="${param.age}"/>

        
        

        <center>
            编号：<jsp:getProperty name="splBean" property="id"/>
            年龄：<jsp:getProperty name="splBean" property="age"/>
        </center>
    </body>
</html>

通过jsp代码可知，可用4种方式设置标记：

<jsp:setProperty name="splBean" property="*"/>

<jsp:setProperty name="splBean" property="id"/>
<jsp:setProperty name="splBean" property="age"/>

<jsp:setProperty name="splBean" property="id" param="id"/>
<jsp:setProperty name="splBean" property="age" param="age"/>

<jsp:setProperty name="splBean" property="id" value="${param.id}"/>

<jsp:setProperty name="splBean" property="age" value="${param.age}"/>

运行结果为：
①输入编号和姓名：

② 返回结果：

先建立一个JavaBean，JavaBean5.java

1 package com.coderdream.bean;
2
3 public class SampleBean4 {
4
5     private String sumIncome = "";
6
7     private String taxStart = "";
8
9     private double tax = 0;
10
11     public SampleBean4() {
12         // TODO 自动生成构造函数存根
13     }
14
15     public String getSumIncome() {
16         return sumIncome;
17     }
18
19     public void setSumIncome(String sumIncome) {
20         this.sumIncome = sumIncome;
21     }
22
23     public double getTax() {
24         return tax;
25     }
26
27     public void setTax(double tax) {
28         this.tax = tax;
29     }
30
31     public String getTaxStart() {
32         return taxStart;
33     }
34
35     public void setTaxStart(String taxStart) {
36         this.taxStart = taxStart;
37     }
38
39     public void calculate() {
40         double totalMoney = Double.parseDouble(sumIncome);
41         double baseMoney = Double.parseDouble(taxStart);
42         double balance = totalMoney - baseMoney;
43
44         System.out.println(totalMoney);
45         System.out.println(baseMoney);
46
47         try {
48             if (balance < 0)
49                 tax = 0;
50             if (balance > 0 && balance <= 500)
51                 tax = balance * 0.05;
52             if (balance > 500 && balance <= 2000)
53                 tax = balance * 0.1 - 25;
54             if (balance > 2000 && balance <= 5000)
55                 tax = balance * 0.15 - 125;
56             if (balance > 5000 && balance <= 20000)
57                 tax = balance * 0.2 - 375;
58             if (balance > 20000 && balance <= 40000)
59                 tax = balance * 0.25 - 1375;
60             if (balance > 40000 && balance <= 60000)
61                 tax = balance * 0.3 - 3375;
62             if (balance > 60000 && balance <= 80000)
63                 tax = balance * 0.35 - 6375;
64             if (balance > 80000 && balance <= 100000)
65                 tax = balance * 0.4 - 10375;
66             if (balance > 100000)
67                 tax = balance * 0.45 - 15375;
68         } catch (Exception e) {
69             System.out.println(e.toString());
70         }
71     }
72
73 }

然后建立两个测试页面：sample3.html和sample8.jsp

sample3.html

1 <html>
2     <head>
3         <title>个人所得税计算器</title>
4         <meta http-equiv="content-type" content="text/html; charset=GB2312">
5     </head>
6
7     <body>
8         <form name="form1" method="post" action="sample8.jsp">
9             <table width="358" height="140" border="0" cellpadding="0"
10                 cellspacing="0" bgcolor="#E6E6E6">
11                 <tr align="center">
12                     <td colspan="3">
13                         <strong>个人所得税计算器</strong>
14                     </td>
15                 </tr>
16                 <tr>
17                     <td colspan="2">
18                         当月个人总收入：
19                     </td>
20                     <td width="177">
21                         <input name="sumIncome" type="text">
22                     </td>
23                 </tr>
24                 <tr>
25                     <td colspan="2">
26                         当地个人所得税起征额：
27                     </td>
28                     <td>
29                         <input name="taxStart" type="text">
30                     </td>
31                 </tr>
32                 <tr align="center">
33                     <td width="161" align="right">
34                         <input type="submit" name="Submit" value="确定">
35                     </td>
36                     <td width="20"></td>
37                     <td align="left">
38                         <input type="reset" name="Reset" value="重填">
39                     </td>
40                 </tr>
41             </table>
42         </form>
43     </body>
44 </html>

sample8.jsp

1 <%@ page language="java" contentType="text/html; charset=GB2312"%>
2 <jsp:useBean id="splBean" class="com.coderdream.bean.SampleBean4" scope="request"></jsp:useBean>
3 <html>
4     <head>
5         <title>个人所得税计算器</title>
6     </head>
7     <body>
8         <%
9             String sumIncome = request.getParameter("sumIncome");
10             String taxStart = request.getParameter("taxStart");
11
12             splBean.setSumIncome(sumIncome);
13             splBean.setTaxStart(taxStart);
14
15             splBean.calculate();
16         %>
17         <center>
18             <p>
19                 当月应缴个人所得税为:
20                 <strong>
21                     <%
22                         out.println(splBean.getTax());
23                     %>
24                 </strong>
25             </p>
26         </center>
27     </body>
28 </html>

输出结果为：

最后，我们设计一个计算器，先建立一个JavaBean，然后新建一个测试页面：
JavaBean5.java

1 package com.coderdream.bean;
2
3 public class SampleBean5 {
4
5     private String first;
6     private String second;
7     private double result;
8     private String operator;
9
10     public SampleBean5() {
11         // TODO 自动生成构造函数存根
12     }
13
14     public String getFirst() {
15         return first;
16     }
17
18     public void setFirst(String first) {
19         this.first = first;
20     }
21
22     public String getOperator() {
23         return operator;
24     }
25
26     public void setOperator(String operator) {
27         this.operator = operator;
28     }
29
30     public double getResult() {
31         return result;
32     }
33
34     public void setResult(double result) {
35         this.result = result;
36     }
37
38     public String getSecond() {
39         return second;
40     }
41
42     public void setSecond(String second) {
43         this.second = second;
44     }
45
46     /*
47      * 根据不同操作符进行计算
48      */
49     public void calculate() {
50
51         try {
52             double one = Double.parseDouble(first);
53             double two = Double.parseDouble(second);
54
55             if (operator.equals("+")) {
56                 result = one + two;
57             } else if (operator.equals("-")) {
58                 result = one - two;
59             } else if (operator.equals("*")) {
60                 result = one * two;
61             } else if (operator.equals("/")) {
62                 result = one / two;
63             }
64         } catch (NumberFormatException e) {
65             // TODO 自动生成 catch 块
66             e.printStackTrace();
67         }
68
69
70     }
71
72 }

sample9.jsp

1 <%@ page language="java" contentType="text/html; charset=GB2312"%>
2 <jsp:useBean id="calculator" scope="request" class="com.coderdream.bean.SampleBean5" >
3     <jsp:setProperty name="calculator" property="*"/>
4 </jsp:useBean>
5 <html>
6   <head>
7     <title>简单计数器</title>
8     <meta http-equiv="content-type" content="text/html; charset=GB2312">
9   </head>
10   <body>
11       <p align="center">
12           <b>简单的计算器</b>
13           <hr>
14           计算结果：
15           <%
16               try {
17                   calculator.calculate();
18                   out.println(calculator.getFirst()
19                                           + calculator.getOperator()
20                                           + calculator.getSecond()
21                                           + " = " +
22                                           + calculator.getResult());
23               } catch (Exception e) {
24                   System.out.println(e);
25               }
26
27           %>
28
29       </p>
30       <hr>
31       <form action="sample9.jsp" method="get">
32           <table>
33               <tr>
34                   <td align="right">第一个参数</td>
35                   <td><input type="text" name="first"></td>
36               </tr>
37               <tr>
38                   <td align="right">操作符</td>
39                   <td>
40
41                       <select name="operator">
42                           <option value="+">+</option>
43                           <option value="-">-</option>
44                           <option value="*">*</option>
45                           <option value="/">/</option>
46                       </select>
47                   </td>
48               </tr>
49               <tr>
50                   <td align="right">第二个参数</td>
51                   <td><input type="text" name="second"></td>
52               </tr>
53             <tr>
54                   <td align="center" colspan="2">
55                       <input type="submit" value="计算">
56                   </td>
57               </tr>
58           </table>
59       </form>
60   </body>
61 </html>

运行结果：

《全文完》

posted on 2006-09-03 23:54 CoderDream 阅读(321) 评论(4) 编辑收藏所属分类: JSP