本文實例講述了jsp通過自定義標簽庫實現數據列表顯示的方法。分享給大家供大家參考，具體如下：
1. 定義標簽庫類 UserListTag.java
package com.yanek.cms.tag;import java.io.IOException;import java.util.ArrayList;import java.util.Iterator;import java.util.List;import javax.servlet.jsp.JspException;import javax.servlet.jsp.tagext.BodyTagSupport;import com.yanek.cms.vo.UserInfo;public class UserListTag extends BodyTagSupport { private String name;// 一個屬性名 private Iterator it;// 要迭代的對象 private int cateid; // 用戶類別id @Override public int doEndTag() throws JspException { try { if (bodyContent != null) { bodyContent.writeOut(bodyContent.getEnclosingWriter()); } } catch (IOException e) { e.printStackTrace(); } return EVAL_PAGE; } @Override public int doStartTag() throws JspException { //這里根據用戶類型,構造不同的列表數據,實現可以根據數據庫獲取 List<UserInfo> users = new ArrayList<UserInfo>(); if (cateid == 1) { users.add(new UserInfo("張三", 20, "Zhangsan@163.com")); users.add(new UserInfo("李四", 30, "Lisi@sina.com")); } else { users.add(new UserInfo("王五", 33, "Wangwu@qq.com")); users.add(new UserInfo("趙六", 33, "zhaoliu@qq.com")); } it = users.iterator(); if (it == null) { return SKIP_BODY; } else { return continueNext(); } } private int continueNext() { if (it.hasNext()) { pageContext.setAttribute(name, it.next(), pageContext.PAGE_SCOPE); return EVAL_BODY_TAG; } else { return SKIP_BODY; } } @Override public int doAfterBody() { return continueNext(); } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getCateid() { return cateid; } public void setCateid(int cateid) { this.cateid = cateid; }}2. 在WEB-INF目錄下 新建標簽庫描述文件my_cms_tag.tld：
my_cms_tag.tld
<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE taglib PUBLIC "-//Sun Microsystems, Inc.//DTD JSP Tag Library 1.1//EN" "http://java.sun.com/j2ee/dtds/web-jsptaglibrary_1_1.dtd"><taglib><tlibversion>1.0</tlibversion><jspversion>1.0</jspversion><shortname>cms</shortname><uri>http://www.58tech.cn/mystruts/tags-cms</uri><!-- userListTag start --> <tag> <name>userListTag</name> <tag-class>com.yanek.cms.tag.UserListTag</tag-class> <body-content>jsp</body-content> <variable> <!--<name-given>user_info</name-given>--> <name-from-attribute>name</name-from-attribute> <variable-class>com.yanek.cms.vo.UserInfo</variable-class> <declare>true</declare> <scope>NESTED</scope> </variable> <attribute> <name>name</name> <required>true</required> </attribute> <attribute> <name>cateid</name> <required>true</required> </attribute></tag><!-- userListTag end --></taglib>
3. web.xml配置
<?xml version="1.0" encoding="UTF-8"?><web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> <taglib> <taglib-uri>/tags/my-cms</taglib-uri> <taglib-location>/WEB-INF/my_cms_tag.tld</taglib-location> </taglib></web-app>
4. jsp調用
<%@ page language="java" import="java.util.*,com.yanek.cms.vo.*" pageEncoding="UTF-8"%><%@ taglib uri="/tags/my-cms" prefix="myTag" %><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html> <head> <base href="<%=basePath%>"> <title>My JSP 'test.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> </head> <body><table width='500px' border='1' align='center'> <tr> <td width='20%'>UserName</td> <td width='20%'>Age</td> <td>Email</td> </tr><myTag:userListTag name="user_info1" cateid="1"> <tr> <td><%=user_info1.getUserName() %></td> <td><%=user_info1.getAge() %></td> <td><%=user_info1.getEmail() %> </td> </tr> </myTag:userListTag></table><hr><table width='500px' border='1' align='center'> <tr> <td width='20%'>UserName</td> <td width='20%'>Age</td> <td>Email</td> </tr><myTag:userListTag name="user_info2" cateid="2"> <tr> <td><%=user_info2.getUserName() %></td> <td><%=user_info2.getAge() %></td> <td><%=user_info2.getEmail() %> </td> </tr> </myTag:userListTag></table> </body></html>
實體類定義
package com.yanek.cms.vo;public class UserInfo { private int age; private String userName; private String email; public int getAge() { return age; } public void setAge(int age) { this.age = age; } public String getUserName() { return userName; } public void setUserName(String userName) { this.userName = userName; } public String getEmail() { return email; } public void setEmail(String email) { this.email = email; } public UserInfo(String userName,int age, String email) { super(); this.age = age; this.userName = userName; this.email = email; } public UserInfo() { }}運行效果如下圖 （URL輸入：http://127.0.0.1:8080/TestCMS/page/userlist.jsp）
完整實例代碼代碼點擊此處本站下載。
希望本文所述對大家Android程序設計有所幫助。
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