Struts2(六)result

一、result简述

result：输出结果；第个Action返回一个字符串，Struts2根据这个值来决定响应结果

name属性：result的逻辑名。和Actin里的返回值匹配，默认"success"

值 ：指定对应的实际资源位置

二、Action中返回其它值

如果Action中返回其它扯，result中的Name属性要与之对应才可以找到指定的资源

Action默认定义了一些常量，可以拿来使用

package com.opensymphony.xwork2;

public interface Action {

    public static final String SUCCESS = "success";

    public static final String NONE = "none";

    public static final String ERROR = "error";

    public static final String INPUT = "input";

    public static final String LOGIN = "login";

}

三、type属性

 <result-types>
            <result-type name="chain" class="com.opensymphony.xwork2.ActionChainResult"/>
            <result-type name="dispatcher" class="org.apache.struts2.dispatcher.ServletDispatcherResult" default="true"/>
            <result-type name="freemarker" class="org.apache.struts2.views.freemarker.FreemarkerResult"/>
            <result-type name="httpheader" class="org.apache.struts2.dispatcher.HttpHeaderResult"/>
            <result-type name="redirect" class="org.apache.struts2.dispatcher.ServletRedirectResult"/>
            <result-type name="redirectAction" class="org.apache.struts2.dispatcher.ServletActionRedirectResult"/>
            <result-type name="stream" class="org.apache.struts2.dispatcher.StreamResult"/>
            <result-type name="velocity" class="org.apache.struts2.dispatcher.VelocityResult"/>
            <result-type name="xslt" class="org.apache.struts2.views.xslt.XSLTResult"/>
            <result-type name="plainText" class="org.apache.struts2.dispatcher.PlainTextResult" />
        </result-types>

这个配置显示了几种常见的结果类型，关于这些以及其他结果类型，各自作用简介如下：
dispatcher: 将请求转发（forward）到本应用程序中指定的资源(JSP 或Servlet)
chain: Action 链式处理，将请求转发（forward）到指定的Action
redirect: 请求重定向到指定的 URL(页面或者Action)
redirectAction: 请求重定向到指定的Action
json：实现Ajax 时返回JSON 对象
freemarker：处理FreeMarker 模板
httpheader：控制特殊HTTP 行为的结果类型
stream：像浏览器发送InputStream 对象，通常用来处理文件下载，还可用于返回Ajax
数据
velocity：处理Velocity 模板
xslt：处理XML/XLST 模板
plainText：显示原始文件内容，例如文件源代码

package com.pb.web.action;
import com.opensymphony.xwork2.ActionSupport;
import com.pb.entity.User;
/*
 * 登录响应action 以javaBean方式接收用户登录输入的用户名和密码
 */
public class LoginAction extends ActionSupport {

    private static final long serialVersionUID = 1L;
    //实例化对象
    private User user;

    //要有execute方法
public String execute(){
    return SUCCESS;
}
public String login(){
    if(user.getUserName().equals("accp") && user.getPassWord().equals("accp")){
        return SUCCESS;
    }else{
        return INPUT;
    }
}

public User getUser() {
    return user;
}

public void setUser(User user) {
    this.user = user;
}

}

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

    <package name="default" namespace="/" extends="struts-default">

    <action name="login" class="com.pb.web.action.LoginAction" method="login">
    <result name="success" type="redirect">
    /loginSuccess.jsp
    </result>
    <result name="input" type="dispatcher">
    /login.jsp
    </result>
    </action>

<package name="user" namespace="/user" extends="struts-default">
<action name="login" class="com.pb.web.action.UserAction">
<result type="chain">
<param name="actionName"> houseAction </param>
<param name="namespace"> / house </param>
</result>
</action>
</package>
<package name="house" namespace="/house" extends="struts-default">
<action name=" houseAction " class="com.pb.web.action.HouseAction">
<result>
/houseSuccess.jsp
</result>
</action>
</package>

四、全局结果

package com.pb.web.action;

import com.opensymphony.xwork2.ActionSupport;

public class HourseAction extends ActionSupport {

    /**
     *
     */
    private static final long serialVersionUID = 1L;
    public String add(){
        System.out.println("执行添加操作！");
    try{
        if(1==1){
        //调用service的方法
            throw new Exception();
        }
    }catch (Exception e){
        e.printStackTrace();
        return ERROR;
    }

        return "success";
    }
    public String update(){
        System.out.println("执行更新操作！");
        try{
            if(1==1){
            //调用service的方法
                throw new Exception();
            }
        }catch (Exception e){
            e.printStackTrace();
            return ERROR;
        }
        return "success";
    }
    public String delete(){
        System.out.println("执行删除操作！");
        try{
            if(1==1){
            //调用service的方法
                throw new Exception();
            }
        }catch (Exception e){
            e.printStackTrace();
            return ERROR;
        }
        return "success";
    }

}

 <global-results>
    <result name="error">/error.jsp</result>
    </global-results>
<!-- <action name="hourse_*" class="com.pb.web.action.HourseAction" method="{1}">
    <result name="success" type="dispatcher">
    {1}success.jsp
    </result>
    </action> -->
    <action name="hourse_add" class="com.pb.web.action.HourseAction" method="add">
    <result name="success" type="dispatcher">
    /loginSuccess.jsp
    </result>
    </action>
    <action name="hourse_update" class="com.pb.web.action.HourseAction" method="update">
    <result name="success" type="dispatcher">
    /loginSuccess.jsp
    </result>
    </action>
    <action name="hourse_delete" class="com.pb.web.action.HourseAction" method="delete">
    <result name="success" type="dispatcher">
    /loginSuccess.jsp
    </result>
    <result name="error">/error1.jsp</result>
    </action>
    </package>

五、动态结果

<%@ 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>登录页面</title>
</head>
<body>
<form action="user/login.action" method="post">
<table>
<tr>
<td>用户名:</td>
<!--这里的name要和提交的地址中声明的实体类.属性来用  -->
<td><input type="text" name="user.username" /></td>
</tr>
<tr>
<td>密码:</td>
<!--这里的name要和提交的地址中声明的实体类.属性来用  -->
<td><input type="password" name="user.password" /></td>
</tr>
<tr>
<td><input type="submit" value="登录" /></td>
<td><input type="reset" value="重置" /></td>
</tr>
</table>
</form>
</body>
</html>

<%@ 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>管理员用户页面</title>
</head>
<body>
管理员用户页面

</body>
</html>

<%@ 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>普通用户</title>
</head>
<body>
普通用户页面
</body>
</html>

User实体类

package com.pb.enity;

public class User {

    private String username;
    private String password;
    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;
    }

}

UserAction

package com.pb.web.action;

import com.opensymphony.xwork2.ActionSupport;
import com.pb.enity.User;

public class UserAction extends ActionSupport {

    private static final long serialVersionUID = 1L;
    private User user;
    //下一个中转的Action
    private String nextDispose;
    public User getUser() {
        return user;
    }
    public void setUser(User user) {
        this.user = user;
    }
    public String getNextDispose() {
        return nextDispose;
    }
    public void setNextDispose(String nextDispose) {
        this.nextDispose = nextDispose;
    }

    public String login(){
        //用户是admin就转到adminAction
        if(user.getUsername().equals("admin") && user.getPassword().equals("admin")){
            nextDispose="admin";
            return SUCCESS;
            //用户是admin就转到commonAction
        }else if(user.getUsername().equals("common") && user.getPassword().equals("common")){
            nextDispose="common";
            return SUCCESS;
            //其它就跳转到登录页面
        }else{
            return INPUT;
        }
    }

}

CommonAction

package com.pb.web.action;

import com.opensymphony.xwork2.ActionSupport;

public class CommonAction extends ActionSupport {

    /**
     *
     */
    private static final long serialVersionUID = 1L;

    @Override
    public String execute() throws Exception {

        return SUCCESS;
    }

}

AdminAction

package com.pb.web.action;

import com.opensymphony.xwork2.ActionSupport;

public class AdminAction extends ActionSupport {

    /**
     *
     */
    private static final long serialVersionUID = 1L;

    @Override
    public String execute() throws Exception {
        // TODO Auto-generated method stub
        return SUCCESS;
    }

}

struts.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!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.enable.DynamicMethodInvocation" value="false" />
    <constant name="struts.devMode" value="true" />

    <!-- Add packages here -->
    <package name="user" namespace="/user" extends="struts-default">
    <action name="login" class="com.pb.web.action.UserAction" method="login">
    <!-- 通过${}取出在UserAciton中定义的变量对应下面的action name -->
    <result name="success" type="redirectAction">${nextDispose}</result>
    <result name="input">/login.jsp</result>
    </action>
    <action name="admin" class="com.pb.web.action.AdminAction">
    <result name="success">/admin.jsp</result>
    </action>
     <action name="common" class="com.pb.web.action.CommonAction">
    <result name="success">/common.jsp</result>
    </action>
    </package>

</struts>