SpringMVC 返回值类型控制 / 跳转方式 / JSON响应

ゞ浴缸里的玫瑰 2022-02-15 09:23 220阅读 0赞

## 一、目录结构 ##

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3poYW5nMTUwMTE0_size_16_color_FFFFFF_t_70]

## 二、SpringMVC返回值类型控制/跳转方式/JSON响应 ##

**1.创建UserController.java**

package com.mollen.controller;
    
    import com.mollen.bean.User;
    import com.sun.deploy.net.HttpResponse;
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.RequestBody;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.ResponseBody;
    import org.springframework.web.servlet.ModelAndView;
    
    import javax.servlet.ServletException;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import javax.servlet.http.HttpSession;
    import java.io.IOException;
    
    /**
     * @ClassName: HelloController
     * @Auther:     Mollen
     * @CreateTime: 2018-11-09  14:49:58
     * @Description:
     */
    
    @Controller
    @RequestMapping(path="/user")
    public class UserController {
    
        /******************************【返回值类型控制】**************************************
    
        /**
         *
         * 1.返回值为字符串：
         *      视图解析器解析为jsp物理路径：/WEB-INF/pages/success.jsp
         */
        @RequestMapping("respStr1")
        public String respStr1(User user, HttpSession session){
            session.setAttribute("login",user);
            return "success";
        }
    
        /**
         *
         * 2.使用request转发页面
         */
        @RequestMapping("respStr2")
        public void respStr2(User user, HttpServletRequest  request, HttpServletResponse response) throws ServletException, IOException {
            request.setAttribute("login",user);
            request.getRequestDispatcher("/WEB-INF/pages/success.jsp").forward(request,response);
        }
    
        /**
         * 3.使用response重定向页面
         */
        @RequestMapping("/respStr3")
        public void respStr3(User user,  HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException {
            response.sendRedirect(request.getContextPath()+"/index.jsp");
        }
    
        /**
         * 4.使用response响应json结果
         */
        @RequestMapping("/respStr4")
        public void respStr4(User user,  HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException {
            //乱码处理
            response.setCharacterEncoding("utf-8");
            response.setContentType("application/json;charset=utf-8");
    
            response.getWriter().write("jsonData");
        }
    
        /**
         * 5.返回ModelAndView
         */
        @RequestMapping("/mv")
        public ModelAndView mv(User user) throws ServletException, IOException {
            ModelAndView mv = new ModelAndView();
            //将数据保存到Model中
            mv.addObject("logined", user);
            //设置视图名称
            mv.setViewName("success");
            return mv;
        }
    
    
        /******************************【页面跳转方式控制】**************************************/
    
        /**
         * 1.转发：forward
         */
         @RequestMapping("/forward")
         public String forward(User user,HttpSession session) throws ServletException, IOException {
             session.setAttribute("logined", user);
             return "forward:/WEB-INF/pages/success.jsp";
         }
    
    
        /**
         * 2.重定向：redirect
         */
        @RequestMapping("/redirect")
        public String redirect(User user,HttpSession session) throws ServletException, IOException {
            session.setAttribute("logined", user);
            return "redirect:/index.jsp";
        }
    
    
        /******************************【响应JSON数据格式】**************************************/
    
        /**
         * 1.接受请求/使用@RequestBody必须是post请求
         * @return
         */
        @RequestMapping(path="/json1")
        public @ResponseBody User  json(@RequestBody User user) {
            System.out.println(user);
            return user;
        }
    
    }

**2.创建response.jsp测试json响应**

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
    <html>
    <head>
        <title>Title</title>
        <script src="js/jquery.min.js"></script>
        <script>
            // 页面加载，绑定单击事件
            $(function(){
                $("#btn").click(function(){
                    // 发送ajax请求
                    $.ajax({
                        // 编写json格式，设置属性和值
                        url:"user/json",
                        contentType:"application/json;charset=UTF-8",
                        data:'{"username":"hehe","password":"123","age":30}',
                        dataType:"json",
                        type:"post",
                        success:function(data){
                            // data服务器端响应的json的数据，进行解析
                            console.log(data);
                        }
                    });
                });
            });
        </script>
    
    </head>
    <body>
    
    <a href="/user/json" >testJson</a>
    <br>
    <button id="btn">发送ajax的请求</button>
    
    </body>
    </html>

**3.web.xml配置**

<?xml version="1.0" encoding="UTF-8"?>
    <web-app>
        
        <servlet>
            <servlet-name>dispatcherServlet</servlet-name>
            <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    
            
            <init-param>
                <param-name>contextConfigLocation</param-name>
                <param-value>classpath:springmvc.xml</param-value>
            </init-param>
    
            
            <load-on-startup>1</load-on-startup>
        </servlet>
    
        <servlet-mapping>
            <servlet-name>dispatcherServlet</servlet-name>
            <url-pattern>/</url-pattern>
        </servlet-mapping>
    
        
        <servlet-mapping>
            <servlet-name>default</servlet-name>
            <url-pattern>*.html</url-pattern>
        </servlet-mapping>
    
        <servlet-mapping>
            <servlet-name>default</servlet-name>
            <url-pattern>*.js</url-pattern>
        </servlet-mapping>
    
        <servlet-mapping>
            <servlet-name>default</servlet-name>
            <url-pattern>*.css</url-pattern>
        </servlet-mapping>
    
        
        <filter>
            <filter-name>characterEncodingFilter</filter-name>
            <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
            <init-param>
                <param-name>encoding</param-name>
                <param-value>UTF-8</param-value>
            </init-param>
        </filter>
    
        <filter-mapping>
            <filter-name>characterEncodingFilter</filter-name>
            <url-pattern>/*</url-pattern>
        </filter-mapping>
    
    </web-app>

**4.pom.xml配置：**

<?xml version="1.0" encoding="UTF-8"?>
    <project xmlns="http://maven.apache.org/POM/4.0.0"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
        <modelVersion>4.0.0</modelVersion>
    
        <groupId>com.mollen</groupId>
        <artifactId>springmvc_exam</artifactId>
        <version>1.0-SNAPSHOT</version>
        <packaging>war</packaging>
    
        <dependencies>
    
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-context</artifactId>
                <version>5.0.3.RELEASE</version>
            </dependency>
    
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-web</artifactId>
                <version>5.0.3.RELEASE</version>
            </dependency>
    
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-webmvc</artifactId>
                <version>5.0.4.RELEASE</version>
            </dependency>
    
            <dependency>
                <groupId>org.apache.tomcat</groupId>
                <artifactId>tomcat-api</artifactId>
                <version>9.0.10</version>
                <scope>provided</scope>
            </dependency>
    
            
            <dependency>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-databind</artifactId>
                <version>2.9.0</version>
            </dependency>
    
            <dependency>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-core</artifactId>
                <version>2.9.0</version>
            </dependency>
    
            <dependency>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-annotations</artifactId>
                <version>2.9.0</version>
            </dependency>
            
        </dependencies>
    
    
    </project>

**5.springmvc.xml配置**

<?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
           xmlns:mvc="http://www.springframework.org/schema/mvc"
           xmlns:context="http://www.springframework.org/schema/context"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="
                http://www.springframework.org/schema/beans
                http://www.springframework.org/schema/beans/spring-beans.xsd
                http://www.springframework.org/schema/mvc
                http://www.springframework.org/schema/mvc/spring-mvc.xsd
                http://www.springframework.org/schema/context
                http://www.springframework.org/schema/context/spring-context.xsd">
    
        
        <context:component-scan base-package="com.mollen"></context:component-scan>
    
        
        <bean id="viewResolver"
              class="org.springframework.web.servlet.view.InternalResourceViewResolver">
            <property name="prefix" value="/WEB-INF/pages/"/>
            <property name="suffix" value=".jsp"></property>
        </bean>
    
        
        <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
            
            <property name="maxUploadSize">
                <value>5242880</value>
            </property>
        </bean>
    
        
        <mvc:annotation-driven></mvc:annotation-driven>
    
    </beans>

原文：[https://blog.csdn.net/mollen/article/details/83993240][https_blog.csdn.net_mollen_article_details_83993240]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3poYW5nMTUwMTE0_size_16_color_FFFFFF_t_70]: /images/20220215/8c35f97b52964d55a34fb88db7f13944.png
[https_blog.csdn.net_mollen_article_details_83993240]: https://blog.csdn.net/mollen/article/details/83993240