SpringMVC05 return (Json)

这里要主要的是js文件要引入，文中不做解释

　　1.导入包

<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/maven-v4_0_0.xsd">
    <parent>
        <artifactId>SpringMVC</artifactId>
        <groupId>cn.happy</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>
    <artifactId>SpringMVC05Return</artifactId>
    <packaging>war</packaging>
    <name>SpringMVC05Return Maven Webapp</name>
    <url>http://maven.apache.org</url>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <!--spring对应的版本号-->
        <spring.version>4.2.1.RELEASE</spring.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.0</version>
            <scope>test</scope>
        </dependency>
        <!--引入需要的spring 核心jar-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-expression</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.alibaba/fastjson -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.1.15</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.8.1</version>
        </dependency>

        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.5.1</version>
        </dependency>
    </dependencies>
    <build>
        <finalName>SpringMVC05Return</finalName>
    </build>
</project>

　　2.配置中央调度器（web.xml）

<!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>
    <!--编码的过滤器-->
    <filter>
        <filter-name>CharactorEncoding</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>
        <init-param>
            <param-name>forceEncoding</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>CharactorEncoding</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
    <!--context-param-->
    <!--config a forward controller-->
    <servlet>
        <servlet-name>springmvc</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <!--init-param-->
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:spring-mvc.xml</param-value>
        </init-param>
        <!--load-on-startup-->
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>springmvc</servlet-name>
        <!--/  it means  we can intercept every request (contains  and *.do and *.css and *.jpg)-->
        <url-pattern>/</url-pattern>
    </servlet-mapping>
</web-app>

　　3.配置映射器（spring-mvc.xml）

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:context="http://www.springframework.org/schema/context"
       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">
    <!--扫描包下的路径-->
    <context:component-scan base-package="cn.happy.controller"/>
    <!--根据注解来寻找路径-->
    <mvc:annotation-driven/>
</beans>

　　4.实体类

public class UserInfo {
    private String name;
    private Integer age;

    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public Integer getAge() {
        return age;
    }
    public void setAge(Integer age) {
        this.age = age;
    }
}

　　5.1：视图页面index.jsp

<%@page contentType="text/html" pageEncoding="UTF-8" isELIgnored="false" %>
<html>
<script type="text/javascript" src="js/jQuery1.11.1.js"></script>
<script tpye="text/javascript">
    $(function () {
        $("[type=button]").click(function () {
            $.ajax({
                url: "/firstJson",　　　　　　　　这个访问路径可以根据需求更换
                type: "post",
                success: function (data) {
                    $.each(data, function (i, dom) {
                        alert(dom.name);
                    })
                }
            })
        })
    })
</script>
<body>
<h2>Hello World!</h2>
<input type="button" value="点我发送Ajax"/>
</body>
</html>

　　5.2：视图页面list.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
<h1>List</h1>
</body>
</html>

　　5.3：视图页面login.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
<form action="/second" method="post">
    用户名：<input name="name"/>
    年龄：<input name="age"/>
    <input type="submit" value="登录"/>
</form>
</body>
</html>

　　5.4视图页面welcome.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" isELIgnored="false" %>
<html>
<body>
<h2>Hello World!</h2>
<h1>欢迎${param.name},年龄：${param.age}</h1>
</body>
</html>

　　6.处理器（一）

import cn.happy.bean.UserInfo;
import com.alibaba.fastjson.JSON;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
@Controller
public class FirstController {
    @RequestMapping("/toJson")
    public void getJson(HttpServletRequest request,HttpServletResponse response) throws IOException {
        List<UserInfo> list=new ArrayList<UserInfo>();
        UserInfo u1=new UserInfo();
        u1.setName("微冷的雨");
        u1.setAge(18);
        UserInfo u2=new UserInfo();
        u2.setName("训练营");
        u2.setAge(28);
        list.add(u1);
        list.add(u2);

        //泛型转json
        String data = JSON.toJSONString(list);

        //我想将data打回浏览器
        response.getWriter().write(data);
    }

}

　　6.2处理器（二）

import cn.happy.bean.UserInfo;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
@Controller
public class JaksonController {
    //返回List集合
    @RequestMapping("/firstJson")
    @ResponseBody
    public Object doFirst() {
        List<UserInfo> list = new ArrayList<UserInfo>();
        UserInfo u1 = new UserInfo();
        u1.setName("微冷的雨");
        u1.setAge(18);
        UserInfo u2 = new UserInfo();
        u2.setName("训练营");
        u2.setAge(28);
        list.add(u1);
        list.add(u2);
        return list;
    }

//返回整型
    @RequestMapping("/secondJson")
    @ResponseBody
    public Object doSecond() {
        return 1;
    }

//返回数字型字符串
    @RequestMapping("/thirdJson")
    @ResponseBody
    public Object doThird() {
        return "1";
    }

//返回对象
    @RequestMapping("/fourJson")
    @ResponseBody
    public Object doFour() {
        UserInfo u1 = new UserInfo();
        u1.setName("微冷的雨");
        u1.setAge(19);
        return u1;
    }

    @RequestMapping("/fiveJson")
    @ResponseBody
    public Object doFive() {
        Map<String, Integer> map = new HashMap<String, Integer>();
        map.put("1", 12);
        map.put("2", 23);
        Map<String, UserInfo> map1 = new HashMap<String, UserInfo>();
        UserInfo u1 = new UserInfo();
        u1.setName("微冷的雨");
        u1.setAge(32);
        UserInfo u2 = new UserInfo();
        u2.setName("训练营");
        u2.setAge(34);
        map1.put(u1.getName(), u1);
        map1.put(u2.getName(), u2);
        return map1;
    }

    @RequestMapping("/six")
    public String doSix(Model model) {
        model.addAttribute("msg", "微冷的雨");
        //转发到页面（默认值）
        return "/index.jsp";
    }

//转换到另外一个控制器方法①
    @RequestMapping("/seven")
    public String doSeven(Model model) {
        model.addAttribute("msg", "微冷的雨");
        return "forward:targetMethod";
    }

//转发到页面②
    @RequestMapping("/targetMethod")
    public String doEight(Model model) {
        System.out.println("=============");
        return "/list.jsp";
    }

//重定向
@RequestMapping("/second")
public String doSecond(Model model, UserInfo info) {
    model.addAttribute("name", info.getName());
    model.addAttribute("age", info.getAge());
    return "redirect:/welcome.jsp";
}

}