拦截器的执行顺序实战

ゝ一世哀愁。 2021-07-25 01:45 341阅读 0赞

**一 视图**

1 loginForm.jsp

<%@ page contentType="text/html; charset=GBK" language="java" errorPage="" %>
    <%@ taglib prefix="s" uri="/struts-tags"%>
    <!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>
        <title>登录页面</title>
    </head>
    <body>
    <h3>用户登录</h3>
    <s:form action="login">
        <s:textfield name="username" label="用户名"/>
        <s:password name="password" label="密码"/>
        <s:submit value="登录"/>
    </s:form>
    </body>
    </html>

2 error.jsp

3 welcome.jsp

**二 配置**

<?xml version="1.0" encoding="GBK"?>
    <!DOCTYPE struts PUBLIC
        "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
        "http://struts.apache.org/dtds/struts-2.3.dtd">
    <struts>
        
        <constant name="struts.i18n.encoding" value="GBK"/>
        
        <package name="lee" extends="struts-default">
            
            <interceptors>
                
                <interceptor name="mySimple"
                class="org.crazyit.app.interceptor.SimpleInterceptor">
                    
                    <param name="name">简单拦截器</param>
                </interceptor>
            </interceptors>
    
            <action name="login" class="org.crazyit.app.action.LoginAction">
                <result name="error">/WEB-INF/content/error.jsp</result>
                <result>/WEB-INF/content/welcome.jsp</result>
                
                <interceptor-ref name="defaultStack"/>
                
                <interceptor-ref name="mySimple">
                    <param name="name">第一个</param>
                </interceptor-ref>
                <interceptor-ref name="mySimple">
                    <param name="name">第二个</param>
                </interceptor-ref>
            </action>
            <action name="*">
                <result>/WEB-INF/content/{1}.jsp</result>
            </action>
        </package>
    </struts>

**三 action**

package org.crazyit.app.action;
    
    import com.opensymphony.xwork2.ActionSupport;
    
    
    public class LoginAction
        extends ActionSupport
    {
        private String username;
        private String password;
        // username的setter和getter方法
        public void setUsername(String username)
        {
            this.username = username;
        }
        public String getUsername()
        {
            return username;
        }
        // password的setter和getter方法
        public void setPassword(String password)
        {
            this.password = password;
        }
        public String getPassword()
        {
            return password;
        }
    
        public String execute() throws Exception
        {
            System.out.println("进入execute方法执行体..........");
            Thread.sleep(1500);
            if (getUsername().equals("crazyit.org")
                && getPassword().equals("leegang") )
            {
                return SUCCESS;
            }
            return ERROR;
        }
    }

**四 拦截器**

package org.crazyit.app.interceptor;
    
    import com.opensymphony.xwork2.ActionInvocation;
    import com.opensymphony.xwork2.interceptor.AbstractInterceptor;
    import java.util.*;
    
    import org.crazyit.app.action.*;
    
    public class SimpleInterceptor
        extends AbstractInterceptor
    {
        // 简单拦截器的名字
        private String name;
        // 为该简单拦截器设置名字的setter方法
        public void setName(String name)
        {
            this.name = name;
        }
        public String intercept(ActionInvocation invocation)
            throws Exception
        {
            // 取得被拦截的Action实例
            LoginAction action = (LoginAction)invocation.getAction();
            // 打印执行开始的时间
            System.out.println(name + " 拦截器的动作---------" +
                "开始执行登录Action的时间为：" + new Date());
            // 取得开始执行Action的时间
            long start = System.currentTimeMillis();
            // 执行该拦截器的后一个拦截器
            // 如果该拦截器后没有其他拦截器，则直接执行Action的被拦截方法
            String result = invocation.invoke();
            // 打印执行结束的时间
            System.out.println(name + " 拦截器的动作---------" +
                "执行完登录Action的时间为：" + new Date());
            long end = System.currentTimeMillis();
            System.out.println(name + " 拦截器的动作---------" +
                "执行完该Action的时间为" + (end - start) + "毫秒");
            return result;
        }
    }

**五 测试**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70]: /images/20210724/3592f65c777548aab4a6247508ab66ac.png