jsp自定义标签获取@Autowride，调用dao层《四》

1.需求

　　自定义标签类中调用smm框架中的dao层，获取数据，在页面展示当前登陆用户的信息。

2.数据库

　　

3.MyTag.java继承RequestContextAwareTag类

package com.zy.tag;

import javax.servlet.jsp.JspWriter;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.servlet.tags.RequestContextAwareTag;
import com.zy.mapper.UserMapper;
import com.zy.pojo.User;

public class MyTag extends RequestContextAwareTag{
 private static final long serialVersionUID = 1L;
 @Autowired
 private UserMapper um;
 @Override
 protected int doStartTagInternal() throws Exception {
   JspWriter out = pageContext.getOut();
   //获取bean
   um =this.getRequestContext().getWebApplicationContext().getBean(UserMapper.class);
   String loginName = (String) pageContext.getSession().getAttribute("loginname");
   User u = um.selectByLoginName(loginName);
   out.write("当前用户的登陆名:"+u.getLoginname()+",性别:"+u.getSex()+",用户名:"+u.getUsername());
   out.flush();
  return 0;
 }

}

4.myTag.tld

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE taglib PUBLIC "-//Sun Microsystems, Inc.//DTD JSP Tag Library 1.2//EN" "http://java.sun.com/dtd/web-jsptaglibrary_1_2.dtd" >
<taglib>
  <tlib-version>1.0</tlib-version>
  <jsp-version>1.0</jsp-version>
  <short-name>myTag</short-name>
  <uri>http://www.zy.myTag</uri>
  <tag>
    <name>loginName</name>
    <tag-class>com.zy.tag.MyTag</tag-class>
    <body-content>scriptless</body-content>
  </tag>
</taglib>

5.jsp

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> 
<%@taglib uri="http://www.zy.myTag" prefix="myTag" %>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>首页</title>
</head>
<body background="../img/body-bg.png">
    <hr/>
    <myTag:loginName/>
</body>
</html>

6.效果

 

posted @ 2018-01-26 16:21  anionic  阅读(998)  评论(0)  编辑  收藏  举报