JavaWeb_(Struts2框架)拦截器interceptor

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　　JavaWeb_(Struts2框架)拦截器interceptor　　传送门

创建拦截器的两种方式

　　第一种：继承MethodFilterInterceptor父类【推荐】

package com.Gary.web.intercept;

import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.MethodFilterInterceptor;

//第一种创建拦截器的方式
public class MyIntercept extends MethodFilterInterceptor{

    @Override
    protected String doIntercept(ActionInvocation invocation) throws Exception {
        

        //放行
        return invocation.invoke();
    }

}

　　

　　第二种：实现Interceptor接口

package com.Gary.web.intercept;

import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.Interceptor;

//第二种创建拦截器的方法
public class Intercept implements Interceptor{

    @Override
    public void destroy() {
        // TODO Auto-generated method stub
        
    }

    @Override
    public void init() {
        // TODO Auto-generated method stub
        
    }

    @Override
    public String intercept(ActionInvocation invocation) throws Exception {
        // TODO Auto-generated method stub
        //放行
        return invocation.invoke();
    }

}

　　在struts.xml中配置拦截器

　　　　<interceptors>
            <!-- 注册拦截器 -->
            <interceptor name="myIntercept" class="com.Gary.web.intercept.MyIntercept"></interceptor>
            <!-- 注册拦截器栈 -->
            <interceptor-stack name="myStack">
                <!-- 引入自己创建的拦截器 -->
                <interceptor-ref name="myIntercept"></interceptor-ref>
                <!-- 引入strtus给你写好的拦截器(20个拦截器) -->
                <interceptor-ref name="defaultStack"></interceptor-ref>
            </interceptor-stack>
        </interceptors>
        
        <!-- 指定包中的默认拦截器栈 -->
        <default-interceptor-ref name="myStack"></default-interceptor-ref>

<?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>
    <constant name="struts.enable.DynamicMethodInvocation" value="true"></constant>

    <!-- name:配置包名 namespace:给action的访问路径定义一个命名空间 -->
    <package name="MyPackage" namespace="/" extends="struts-default">
    
        
        <interceptors>
            <!-- 注册拦截器 -->
            <interceptor name="myIntercept" class="com.Gary.web.intercept.MyIntercept"></interceptor>
            <!-- 注册拦截器栈 -->
            <interceptor-stack name="myStack">
                <!-- 引入自己创建的拦截器 -->
                <interceptor-ref name="myIntercept"></interceptor-ref>
                <!-- 引入strtus给你写好的拦截器(20个拦截器) -->
                <interceptor-ref name="defaultStack"></interceptor-ref>
            </interceptor-stack>
        </interceptors>
        
        <!-- 指定包中的默认拦截器栈 -->
        <default-interceptor-ref name="myStack"></default-interceptor-ref>
    
        <!-- 增加动态方法调用的安全性 -->
        <global-allowed-methods>regex:.*</global-allowed-methods>
    
        <!-- action:配置action类
            name：决定了action访问的资源名称  servlet:url-pattern 
            class:action的完整类名
            method:指定调用action中的哪个方法来去处理请求  -->
            
        <action name="LoginAction_*" class="com.Gary.web.UserAction" method="{1}">
            <!-- 默认为转发  redirect设置为重定向  -->
            <result name="success" type="redirect">/index.html</result>
            <!-- 默认为转发 -->
            <result name="error">/login.jsp</result>
        </action>


        <action name="LoginActionDefault" class="com.Gary.web.DefaultAction" method="execute">
        
        </action>
        
        <action name="LoginActionImpl_*" class="com.Gary.web.ImplAction" method="{1}">
            <!-- 转发到LoginActionDefault -->
            <result name="defaultAction" type="chain">LoginActionDefault</result>

            <!-- 重定向到Action(LoginAction_*) -->
            <result name="toLogin" type="redirectAction">
                <param name="actionName">LoginAction_login</param>
                
                <param name="username">${username}</param>
                <param name="password">${password}</param>
            </result>
            
        </action>
    </package>
    
    
    <package name="PastePackage" namespace="/" extends="struts-default">
        <global-allowed-methods>regex:.*</global-allowed-methods>
        <action name="PasteAction_*" class="com.Gary.web.PasteAction" method="{1}">
            <result name="index">/index.jsp</result>
        </action>
    
    </package>
    
    
    
    
    
</struts>

　　配置拦截器(拦截器只能控制访问Action,不能控制访问jsp)

　　在UserAction.java中当用户登陆成功时，放置user到ActionContext域中

boolean success = userService.findUser(user);
        
        if(success)
        {
            ActionContext.getContext().getSession().put("user", user);
            return "success";
        }else{
            ServletActionContext.getRequest().setAttribute("error", "用户名或密码错误！！！");
            return "error";
        }

　　实现MyIntercept.java拦截器

protected String doIntercept(ActionInvocation invocation) throws Exception {
        
        System.out.println("MyIntercept");
        
        
        //获取session
        Map<String, Object> session = ActionContext.getContext().getSession();
        //获取session中的user
        Object object = session.get("user");
        //判断session中是否有数据
        if(object!=null)
        {
            //有，放行
            return invocation.invoke();
        }
        else
        {
            //没有，重定向到login.jsp
            return "toLogin";
        }
            
    }

　　局部拦截器

        <action name="LoginActionDefault" class="com.Gary.web.DefaultAction" method="execute">
            <result name="tologin" type="redirect">/login.jsp</result>
        </action>

　　全局拦截器：如果每一个action都要单独配置一个局部兰机器，就会显得很麻烦，这时就可以使用<global-results>标签配置全局拦截器

        <default-interceptor-ref name="myStack"></default-interceptor-ref>
        <global-results>
            <result name="toLogin" type="redirect">/login.jsp</result>
        </global-results>

　　配置放行登陆方法login的拦截器

        <interceptors>
            <!-- 注册拦截器 -->
            <interceptor name="myIntercept" class="com.Gary.web.intercept.MyIntercept"></interceptor>
            <!-- 注册拦截器栈 -->
            <interceptor-stack name="myStack">
                <!-- 引入自己创建的拦截器 -->
                <interceptor-ref name="myIntercept">
                    <param name="excludeMethods">login</param>
                </interceptor-ref>
                <!-- 引入strtus给你写好的拦截器(20个拦截器) -->
                <interceptor-ref name="defaultStack"></interceptor-ref>
            </interceptor-stack>
        </interceptors>

　　此时，当用户未登录时，拦截器会拦截LoginActionDefault请求，并重定向到login.jsp中。当用户登陆后，会放行LoginActionDefault请求，并在控制台输出通过System.err.println("这是一个普通的action");输出红色的【这是一个普通的action】

　　

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@taglib uri="/struts-tags" prefix="s"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
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</head>
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                </s:iterator>

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                    <div class="userdeital">大牛6级 豆:14006</div>
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                <image class="userface" src="images/2.gif" />
                <div class="dvuser">
                    <div class="userTitle">陈有龙</div>
                    <div class="userdeital">大牛6级 豆:14006</div>
                </div>
            </div>
            <div class="users">
                <image class="userface" src="images/3.gif" />
                <div class="dvuser">
                    <div class="userTitle">陈有龙</div>
                    <div class="userdeital">大牛6级 豆:14006</div>
                </div>
            </div>
            <div class="users">
                <image class="userface" src="images/4.gif" />
                <div class="dvuser">
                    <div class="userTitle">陈有龙</div>
                    <div class="userdeital">大牛6级 豆:14006</div>
                </div>
            </div>
            <div class="users">
                <image class="userface" src="images/5.gif" />
                <div class="dvuser">
                    <div class="userTitle">陈有龙</div>
                    <div class="userdeital">大牛6级 豆:14006</div>
                </div>
            </div>
            <div class="users">
                <image class="userface" src="images/6.gif" />
                <div class="dvuser">
                    <div class="userTitle">陈有龙</div>
                    <div class="userdeital">大牛6级 豆:14006</div>
                </div>
            </div>


        </div>

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</div>
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    {

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        {
            $(".tabheads").removeClass("tabcurrent").eq($(this).index()).addClass("tabcurrent");
            $(".tab").hide().eq($(this).index()).show();
        });
    });
</script>
<body>
</body>
</html>

<?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>
    <constant name="struts.enable.DynamicMethodInvocation" value="true"></constant>

    <!-- name:配置包名 namespace:给action的访问路径定义一个命名空间 -->
    <package name="MyPackage" namespace="/" extends="struts-default">
    
        
        <interceptors>
            <!-- 注册拦截器 -->
            <interceptor name="myIntercept" class="com.Gary.web.intercept.MyIntercept"></interceptor>
            <!-- 注册拦截器栈 -->
            <interceptor-stack name="myStack">
                <!-- 引入自己创建的拦截器 -->
                <interceptor-ref name="myIntercept">
                    <param name="excludeMethods">login</param>
                </interceptor-ref>
                <!-- 引入strtus给你写好的拦截器(20个拦截器) -->
                <interceptor-ref name="defaultStack"></interceptor-ref>
            </interceptor-stack>
        </interceptors>
        
        <!-- 指定包中的默认拦截器栈 -->
        <default-interceptor-ref name="myStack"></default-interceptor-ref>
        <global-results>
            <result name="toLogin" type="redirect">/login.jsp</result>
        </global-results>
    
        <!-- 增加动态方法调用的安全性 -->
        <global-allowed-methods>regex:.*</global-allowed-methods>
    
        <!-- action:配置action类
            name：决定了action访问的资源名称  servlet:url-pattern 
            class:action的完整类名
            method:指定调用action中的哪个方法来去处理请求  -->
            
        <action name="LoginAction_*" class="com.Gary.web.UserAction" method="{1}">
            <!-- 默认为转发  redirect设置为重定向  -->
            <result name="success" type="redirect">/index.html</result>
            <!-- 默认为转发 -->
            <result name="error">/login.jsp</result>
        </action>


        <action name="LoginActionDefault" class="com.Gary.web.DefaultAction" method="execute">
            
        </action>
        
        <action name="LoginActionImpl_*" class="com.Gary.web.ImplAction" method="{1}">
            <!-- 转发到LoginActionDefault -->
            <result name="defaultAction" type="chain">LoginActionDefault</result>

            <!-- 重定向到Action(LoginAction_*) -->
            <result name="toLogin" type="redirectAction">
                <param name="actionName">LoginAction_login</param>
                
                <param name="username">${username}</param>
                <param name="password">${password}</param>
            </result>
            
        </action>
    </package>
    
    
    <package name="PastePackage" namespace="/" extends="struts-default">
        <global-allowed-methods>regex:.*</global-allowed-methods>
        <action name="PasteAction_*" class="com.Gary.web.PasteAction" method="{1}">
            <result name="index">/index.jsp</result>
        </action>
    
    </package>
    
    
    
    
    
</struts>

package com.Gary.web.intercept;

import java.util.Map;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.MethodFilterInterceptor;

//第一种创建拦截器的方式
public class MyIntercept extends MethodFilterInterceptor{

    @Override
    protected String doIntercept(ActionInvocation invocation) throws Exception {
        
        System.out.println("MyIntercept");
        
        
        //获取session
        Map<String, Object> session = ActionContext.getContext().getSession();
        //获取session中的user
        Object object = session.get("user");
        //判断session中是否有数据
        if(object!=null)
        {
            //有，放行
            return invocation.invoke();
        }
        else
        {
            //没有，重定向到login.jsp
            return "toLogin";
        }
            
    }

}