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Structs复习访问web元素

Structs帮我们在action和http里建立了联系

主要有四种方式我们主要用第二种（IOC 依赖容器注入）

Jar包

web.XML

<?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>
  
  <filter>
        <filter-name>struts2</filter-name>
        <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
    </filter>

    <filter-mapping>
        <filter-name>struts2</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
</web-app>

Struct.xml(每次换类名

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
    "http://struts.apache.org/dtds/struts-2.0.dtd">

<struts>
    <constant name="struts.devMode" value="true" />
    <package name="login" extends="struts-default" namespace="/login">
        <action name="login*" class="com.bjsxt.struts2.user.action.LoginAction{1}">
            <result>/user_login_success.jsp</result>
        </action>
    </package>
</struts>

拿的时候

index.jsp

<?xml version="1.0" encoding="GB18030" ?>
<%@ page language="java" contentType="text/html; charset=GB18030"
    pageEncoding="GB18030"%>

<% String context = request.getContextPath(); %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GB18030" />
<title>Insert title here</title>
</head>
<body>
取得Map类型request,session,application,真实类型 HttpServletRequest, HttpSession, ServletContext的引用:
<ol>
    <li>前三者：依赖于容器</li>
    <li>前三者：IOC</li> (只用这种)
    <li>后三者：依赖于容器</li>
    <li>后三者：IOC</li>
</ol>
<br />
<form name="f" action="" method="post">
用户名：<input type="text" name="name"/>
密码：<input type="text" name="password"/>
<br />
<input type="button" value="submit1" onclick="javascript:document.f.action='login/login1';document.f.submit();" />
<input type="button" value="submit2" onclick="javascript:document.f.action='login/login2';document.f.submit();" />
<input type="button" value="submit3" onclick="javascript:document.f.action='login/login3';document.f.submit();" />
<input type="button" value="submit4" onclick="javascript:document.f.action='login/login4';document.f.submit();" />
</form>
    
</body>
</html>

user_login_success.jsp

<?xml version="1.0" encoding="GB18030" ?>
<%@ page language="java" contentType="text/html; charset=GB18030"
    pageEncoding="GB18030"%>
    <%@taglib uri="/struts-tags" prefix="s" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GB18030" />
<title>Insert title here</title>
</head>
<body>
    User Login Success!
    <br />
    <s:property value="#request.r1"/> | <%=request.getAttribute("r1") %> <br />
    <s:property value="#session.s1"/> | <%=session.getAttribute("s1") %> <br />
    <s:property value="#application.a1"/> | <%=application.getAttribute("a1") %> <br />
    <s:property value="#attr.a1"/><br />     //不常用 无法精确的知道到底存在哪里 他是吧request application session 的全部存在里面
    <s:property value="#attr.s1"/><br />
    <s:property value="#attr.r1"/><br />
    <s:debug></s:debug>
    <br />
</body>
</html>

先介绍第一种‘

LoginAction1

package com.bjsxt.struts2.user.action;

import java.util.Map;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;

public class LoginAction1 extends ActionSupport {
    
    private Map request;
    private Map session;
    private Map application;
    
    public LoginAction1() {
        request = (Map)ActionContext.getContext().get("request");
        session = ActionContext.getContext().getSession();
        application = ActionContext.getContext().getApplication();
    }
    
    public String execute() {
        request.put("r1", "r1");
        session.put("s1", "s1");
        application.put("a1", "a1");
        return SUCCESS; 
    }
    
    
}

第二种： IOC控制反转依赖于容器

LoginAction2

package com.bjsxt.struts2.user.action;

import java.util.Map;

import org.apache.struts2.interceptor.ApplicationAware;
import org.apache.struts2.interceptor.RequestAware;
import org.apache.struts2.interceptor.SessionAware;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;

public class LoginAction2 extends ActionSupport implements RequestAware,SessionAware, ApplicationAware {
    
    private Map<String, Object> request;
    private Map<String, Object> session;
    private Map<String, Object> application;
    
    //DI dependency injection
    //IoC inverse of control
    public String execute() {
        request.put("r1", "r1");
        session.put("s1", "s1");
        application.put("a1", "a1");
        return SUCCESS; 
    }

    @Override
    public void setRequest(Map<String, Object> request) {
        this.request = request;
    }

    @Override
    public void setSession(Map<String, Object> session) {
        this.session = session;
    }

    @Override
    public void setApplication(Map<String, Object> application) {
        this.application = application;
    }
    
    
}

第三种

LoginAction3

package com.bjsxt.struts2.user.action;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;

import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionSupport;

public class LoginAction3 extends ActionSupport {
    
    private HttpServletRequest request;
    private HttpSession session;
    private ServletContext application;
    
    public LoginAction3() {
        request = ServletActionContext.getRequest();
        session = request.getSession();
        application = session.getServletContext();
    }
    
    public String execute() {
        request.setAttribute("r1", "r1");
        session.setAttribute("s1", "s1");
        application.setAttribute("a1", "a1");
        return SUCCESS; 
    }
    
}

第四种 IOC

package com.bjsxt.struts2.user.action;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;

import org.apache.struts2.interceptor.ServletRequestAware;

import com.opensymphony.xwork2.ActionSupport;

public class LoginAction4 extends ActionSupport implements ServletRequestAware {
    
    private HttpServletRequest request;
    private HttpSession session;
    private ServletContext application;
    
    
    
    public String execute() {
        request.setAttribute("r1", "r1");
        session.setAttribute("s1", "s1");
        application.setAttribute("a1", "a1");
        return SUCCESS; 
    }



    @Override
    public void setServletRequest(HttpServletRequest request) {
        this.request = request;
        this.session = request.getSession();
        this.application = session.getServletContext();
    }
    
}

LoginAction4

查看全文

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原文地址：https://www.cnblogs.com/frankzone/p/9467709.html

Structs复习 访问web元素

Structs复习访问web元素