Struts2自解拦截器

电玩女神 2022-03-06 18:59 100阅读 0赞

关于Struts2中的拦截器，本人是通过一个跳转的小例子来理解的，详见下方代码：

**index.jsp**(首页)

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <%@ taglib prefix="s" uri="/struts-tags" %>    
    <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    <html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>Insert title here</title>
    </head>
    <body>
    	<form action="login.action">
    	 
    		用户：<input type="text" name="username"><br>
    		密码：<input type="password" name="password"><br>
    		<input type="submit" value="提交">
    	</form>
    </body>
    </html>

**struts.xml**(配置文件)

<?xml version="1.0" encoding="UTF-8"?>
    <!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.5//EN" "http://struts.apache.org/dtds/struts-2.5.dtd" >
    <struts>
    	
    	<constant name="struts.devMode" value="true"></constant>
    	<package name="a1" namespace="/" extends="struts-default">
    			
    			<interceptors>
    				
    				<interceptor name="loginCheck" class="com.zte.interceptor.LoginInterceptor">
    				</interceptor>
    				
    				<interceptor-stack name="check">
    					<interceptor-ref name="loginCheck"></interceptor-ref>
    				</interceptor-stack>
    			</interceptors>
    			
    			
    			<global-results>
    				<result name="login">/index.jsp</result>
    			</global-results>
    			
    		<action name="login" class="com.zte.LoginAction" method="execute">
    			
    			<result name="success" type="dispatcher">/success.jsp</result>
    
    		</action>
    		<action name="bookInput" class="com.zte.BookAction" >
    			 
    			
    			<interceptor-ref name="loginCheck"></interceptor-ref>
    
    			<result name="success">/book.jsp</result>
    		</action>
    	</package>
    	
    </struts>

**LoginAction.java**(属性驱动处理请求参数)

package com.zte;
    
    import com.opensymphony.xwork2.ActionContext;
    
    public class LoginAction { 
    	
    	private String username;
    	private String password;
    	
    	
    	public String execute(){ 
    		System.out.println("username:" + username);
    		if (username != null && !"".equals(username)){ 
    			ActionContext ctx = ActionContext.getContext();
    			ctx.getSession().put("user", username);
    			
    		}
    		return "success";
    	}
    	public String getUsername() { 
    		return username;
    	}
    	public void setUsername(String username) { 
    		this.username = username;
    	}
    	public String getPassword() { 
    		return password;
    	}
    	public void setPassword(String password) { 
    		this.password = password;
    	}
    
    }

**success.jsp**

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    <html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>Insert title here</title>
    </head>
    <body>
    	用户：${username }<br>
    	<a href="bookInput.action">图书信息</a>
    </body>
    </html>

**LoginInterceptor.java**(实现拦截)

package com.zte.interceptor;
    
    import com.opensymphony.xwork2.ActionContext;
    import com.opensymphony.xwork2.ActionInvocation;
    import com.opensymphony.xwork2.interceptor.Interceptor;
    
    public class LoginInterceptor implements Interceptor { 
    
    	@ Override
    	public String intercept(ActionInvocation invocation) throws Exception { 
    		System.out.println("aaaaaaaaa");
    		ActionContext ctx = ActionContext.getContext();
    		
    		System.out.println(ctx.getSession().get("user"));
    		if (ctx.getSession().get("user")== null) { 
    			return "login";
    		} else { 
    			return invocation.invoke();
    		}
    	}
    	
    	@Override
    	public void destroy() { 
    		// 销毁拦截器时做的工作
    		// 只做一次
    	}
    
    	@Override
    	public void init() { 
    		// 初始化拦截器时要做的工作
    		// 只做一次
    	}
    }

**BookAction.java**

package com.zte;
    
    import com.opensymphony.xwork2.ActionContext;
    
    public class BookAction { 
    	
    	public String execute(){ 
    		/* ActionContext ctx = ActionContext.getContext(); //用户未正常登陆 if (ctx.getSession().get("user") == null){ return "login"; } */
    		System.out.println("aaaaa");
    		return "success";
    	}
    }

整个流程就上述那么多，例外这是我的目录结构，方便大家查看。  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1lZeGlhb2JhbzA3MjY_size_16_color_FFFFFF_t_70]  
    有任何问题的请在下方评论留言，谢谢。

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