zoukankan      html  css  js  c++  java
  • Struts2初步认识

    Struts2 由 struts.xml  xxx.java  web.xml xxx.jsp 组成

    执行的规则是:首先访问 xxx1.jsp ,显示 xx1.jsp 界面,一番操作后访问服务器的请求被 web.xml 拦截,然后对应的 struts.xml 中 action 被激活,action 中相应的类 xxx.java 执行,执行后放回一个 String 类型的值,然后继续查找 action 中 result 的 name 属性,执行相应 result 对应的 xxx2.jsp

    项目图:

    web.xml 是配置拦截器的。

    <?xml version="1.0" encoding="UTF-8"?>
    <web-app version="3.0" 
        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_3_0.xsd">
      <display-name></display-name>    
      <welcome-file-list>  未指定打开界面时,系统自动选择的最开始的界面(这里是列表,可以有多项)
        <welcome-file>index.jsp</welcome-file>  欢迎界面,优先级从上到下
      </welcome-file-list>
      <filter> 拦截器
          <filter-name>struts2</filter-name>拦截器名称
          <filter-class> 拦截器使用的拦截类类
              org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter
          </filter-class>
      </filter>
      <filter-mapping>拦截器映射
          <filter-name>struts2</filter-name>要对应前面的名称
          <url-pattern>/*</url-pattern>拦截的类型
      </filter-mapping></web-app>

    xxx.jsp

    <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
    <%
    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 'index.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>
        <form action="zhua">   此处的action要对应Struts.xml中配置的action名称!!!!!!!!!!!!!!
            <ul style="list-style-type: none;"> 
                <li>账号:<input type="text" name="zhanghao"> </li>
                <li>密码:<input type="text" name="mima"> </li>
                <li><input type="submit" value="提交"> </li>
            </ul>
        </form>  
      </body>
    </html>

    struts.xml

    <?xml version="1.0" encoding="UTF-8" ?>
    <!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.1//EN" "http://struts.apache.org/dtds/struts-2.1.dtd">
    <struts>
        <package name="sss" extends="struts-default"> 包名可以自己定,扩展 struts-default(默认的)(不知道原因)
            <action name="zhua" class="text.Zhua"> action!!名称为 zhua ,对应的类为 text.Zhua (action的名称应与 xxx.jsp中form标签的action一致)
                <result name="ok">/ok.jsp</result> 对应返回值,显示相应的界面
                <result name="no">/no.jsp</result>
            </action>
        </package>
    </struts>    

    xxx.java

    package text;
    
    import com.opensymphony.xwork2.ActionSupport;
    
    public class Zhua extends ActionSupport 继承类
    {
        private String zhanghao; 定义账号与密码
        private String mima;
        public String getZhanghao()
        {
            return zhanghao;
        }
        public void setZhanghao(String zhanghao)
        {
            this.zhanghao = zhanghao;
        }
        public String getMima()
        {
            return mima;
        }
        public void setMima(String mima)
        {
            this.mima = mima;
        }
        @Override
        public String execute() throws Exception 重要的方法
        {
            System.out.println(zhanghao+mima);
            // TODO Auto-generated method stub
            if(zhanghao.equals("chen"))
            {
                if(mima.equals("chang"))
                {
                    return "ok"; 返回值ok
                }
            }
            return "xx"; 返回值no
        }
    }

    ok.jsp 跳转的界面 ,基本不用改动

    <%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
    <%
    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 'ok.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>
        ok <br> 唯一更改的地方
      </body>
    </html>
  • 相关阅读:
    设计模式-观察者模式
    ps一寸照的编辑
    ps剪切蒙版的使用
    ps扣头发
    mysql索引优化
    ES6 $ ES5
    sping-mybatis集成
    多线程--volatile
    eclipse.exe打开是报错
    Spring Aop 详解二
  • 原文地址:https://www.cnblogs.com/cchjl/p/6504771.html
Copyright © 2011-2022 走看看