JAVA网络爬虫
HttpClient

导航

 
SpringMVC响应数据的几种方式

SpringMVC响应数据的几种方式

项目结构

在这里插入图片描述

配置文件

  1. pom.xml

    <?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.xiaoge</groupId>
  <artifactId>springmvc_response</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>war</packaging>

  <name>springmvc_response Maven Webapp</name>
  <!-- FIXME change it to the project's website -->
  <url>http://www.example.com</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.7</maven.compiler.source>
    <maven.compiler.target>1.7</maven.compiler.target>
    <spring.version>5.0.2.RELEASE</spring.version>
  </properties>

  <dependencies>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-web</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>${spring.version}</version>
    </dependency>


    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>servlet-api</artifactId>
      <version>2.5</version>
      <scope>provided</scope>
    </dependency>

    <dependency>
      <groupId>javax.servlet.jsp</groupId>
      <artifactId>jsp-api</artifactId>
      <version>2.0</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>

  <build>
    <finalName>springmvc_response</finalName>
    <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
      <plugins>
        <plugin>
          <artifactId>maven-clean-plugin</artifactId>
          <version>3.1.0</version>
        </plugin>
        <!-- see http://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_war_packaging -->
        <plugin>
          <artifactId>maven-resources-plugin</artifactId>
          <version>3.0.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-compiler-plugin</artifactId>
          <version>3.8.0</version>
        </plugin>
        <plugin>
          <artifactId>maven-surefire-plugin</artifactId>
          <version>2.22.1</version>
        </plugin>
        <plugin>
          <artifactId>maven-war-plugin</artifactId>
          <version>3.2.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-install-plugin</artifactId>
          <version>2.5.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-deploy-plugin</artifactId>
          <version>2.8.2</version>
        </plugin>
      </plugins>
    </pluginManagement>
  </build>
</project>

  2. web.xml**(重点:配置解决中文乱码的过滤器)**

    <!DOCTYPE web-app PUBLIC
 "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
 "http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
  <display-name>Archetype Created Web Application</display-name>

  <!-- 前端控制器 -->
  <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:spring.xml</param-value>
    </init-param>

    <!-- 当启动服务器的时候创建servlet对象 -->
    <load-on-startup>1</load-on-startup>

  </servlet>

  <servlet-mapping>
    <servlet-name>dispatcherServlet</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

  <!-- 配置解决中文乱码的过滤器 -->
  <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>

  3. spring.xml

    <?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        https://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/mvc
        https://www.springframework.org/schema/mvc/spring-mvc.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd">

    <!-- 开启扫描注解 -->
    <context:component-scan base-package="com.xiaoge"></context:component-scan>

    <!-- 视图解析器 -->
    <bean id="internalResourceViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/pages/"></property>
        <property name="suffix" value=".jsp"></property>
    </bean>

    <!-- 前端控制器, 那些静态资源不拦截 -->
    <!-- css目录下的所有资源不拦截 -->
    <mvc:resources  location="/css/" mapping="/css/**" />
    <!-- images目录下的所有资源不拦截 -->
    <mvc:resources  location="/images/" mapping="/images/**" />
    <!-- js目录下的所有资源不拦截 -->
    <mvc:resources  location="/js/" mapping="/js/**" />

    <!-- 开启SpringMVC注解 -->
    <mvc:annotation-driven ></mvc:annotation-driven>
</beans>

实体类

  1. User

    package com.xiaoge.domain;

/**
 * @Author: 潇哥
 * @DateTime: 2020/4/20 下午8:32
 * @Description: 用户实体类
 */
public class User {

    private String username;
    private String password;
    private Integer age;

    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;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    @Override
    public String toString() {
        return "User{" +
                "username='" + username + '\'' +
                ", password='" + password + '\'' +
                ", age=" + age +
                '}';
    }
}

控制器

  1. UserController

    package com.xiaoge.controller;

import com.xiaoge.domain.User;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
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 java.io.IOException;

/**
 * @Author: 潇哥
 * @DateTime: 2020/4/20 下午8:29
 * @Description: 控制器
 */
@Controller
@RequestMapping("/user")
public class UserController {

    /**
     * 返回String
     * @param model
     * @return
     */
    @RequestMapping("testString")
    public String testString(Model model){
        System.out.println("testString执行了");

        // 模拟数据去查询
        User user = new User();
        user.setUsername("小美");
        user.setPassword("123");
        user.setAge(12);

        // 把数据存储到model, 就是request域中
        model.addAttribute("user", user);

        return "success";

    }

    /**
     * 返回void
     * 请求: 转发是一次请求, 不用编写项目的名称
     * @param request
     * @param response
     * @return
     */
    @RequestMapping("testVoid")
    public void testVoid(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        System.out.println("testVoid执行了");
        // 编写请求转发的程序
        // request.getRequestDispatcher("/WEB-INF/pages/success.jsp").forward(request, response);


        // 重定向
        // response.sendRedirect(request.getContextPath() + "/index.jsp");

        // 设置中文乱码
        response.setCharacterEncoding("utf-8");
        response.setContentType("text/html;charset=utf-8");

        // 直接进行响应
        response.getWriter().write("哈哈");

        return ;

    }


    /**
     * 返回ModelAndView
     * @return
     */
    @RequestMapping("testModelAndView")
    public ModelAndView testModelAndView(){
        System.out.println("testModelAndView执行了");

        ModelAndView mv = new ModelAndView();


        User user = new User();
        user.setUsername("小花");
        user.setPassword("456");
        user.setAge(123);

        // 把user对象存储到mv对象中, 也会把user对象存入到request域中
        mv.addObject("user", user);

        // 会根据视图解析器, 去找success对应的jsp页面
        mv.setViewName("success");

        return mv;

    }


    /**
     * 使用关键字的方式进行转发或者重定向
     * @return
     */
    @RequestMapping("testForwardOrRedirect")
    public String testForwardOrRedirect(){
        System.out.println("testForwardOrRedirect执行了");

        // SpringMVC内置的关键字转发和重定向

        // 转发 (forward: 固定写法)
        // return "forward:/WEB-INF/pages/success.jsp";

        // 重定向 (redirect: 固定写法, 这里不需要加项目名称, SpringMVC已经帮你处理好了)
        return "redirect:/index.jsp";

    }

    /**
     * 返回User json对象
     *
     * @RequestBody
     * 使用@ResponseBody 注解实现将 controller 方法返回对象转换为 json 响应给客户端。
     *
     * SpringMVC 默认用 MappingJacksonHttpMessageConverter 对 json 数据进行转换，
     * 需要加入 jackson 的包。
     *
     * @param user
     * @return
     */
    @RequestMapping("testAjax")
    public @ResponseBody User testAjax(@RequestBody User user){
        System.out.println("testAjax执行了");

        // 客户端发送ajax的请求, 传的是json字符串, 后端把json字符串封装到user对象中
        System.out.println(user);

        // 做响应, 模拟查询数据库
        user.setUsername("小张");
        user.setPassword("456");
        user.setAge(18);

        // 做响应
        return user;

    }


}

前台页面

  1. index.jsp

    <%--
  Created by IntelliJ IDEA.
  User: xiaoge
  Date: 2020/4/20
  Time: 下午8:19
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>重定向</title>
</head>
<body>
    重定向
</body>
</html>

  2. response.jsp

    <%--
  Created by IntelliJ IDEA.
  User: xiaoge
  Date: 2020/4/20
  Time: 下午8:30
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>测试</title>
    <script src="js/jquery.min.js"></script>
    <script>
        $(function(){
            $("#btn").click(function(){
                // 发送ajax请求
                $.ajax({
                    // 编写json格式, 设置属性和值
                    url: "user/testAjax",
                    type: "post",
                 contentType: "application/json",
                    data: '{"username": "张三", "password": "123", "age": 20}',
                    dataType: "json",
                    success: function(data){
                        // data服务器端响应的json的数据, 进行解析
                        alert(data);
                        alert(data.username);
                        alert(data.password);
                        alert(data.age);
                    }
                });
            })
        })
    </script>
</head>
<body>
    <%--返回值String--%>
    <a href="user/testString">testString</a>
    <br />


    <%--无返回值--%>
    <a href="user/testVoid">testVoid</a>
    <br />

    <%--返回值ModelAndView--%>
    <a href="user/testModelAndView">testModelAndView</a>
    <br />

    <%--关键字转发和重定向--%>
    <a href="user/testForwardOrRedirect">testForwardOrRedirect</a>
    <br />

    <%--发送ajax--%>
    <button id="btn">发送ajax</button>
    <br />

</body>
</html>

  3. success.jsp

    <%--
  Created by IntelliJ IDEA.
  User: xiaoge
  Date: 2020/4/20
  Time: 下午8:19
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" isELIgnored="false" %>
<html>
<head>
    <title>成功</title>
</head>
<body>
    <h3>成功</h3>
    ${user.username}
    ${user.password}
    ${user.age}
</body>
</html>
posted on 2020-04-25 18:49  gmlgxx  阅读(49)  评论(0)    收藏  举报
 
博客园  ©  2004-2025
浙公网安备 33010602011771号 浙ICP备2021040463号-3