SpringMVC(十三)：SpringMVC 与fastjson集成

1）fastjson jar包下载地址：https://sourceforge.net/projects/fastjson/
下载完成后需要把jar包拷贝到WEB-INF/lib文件夹中。
2）使用pom.xml配置：
如果你使用了Maven，maven repository配置如下：

<repository>
    <id>opensesame</id>
    <name>Alibaba OpenSource Repsoitory</name>
    <url>http://code.alibabatech.com/mvn/releases/</url>
    <snapshots>
        <enabled>false</enabled>
    </snapshots>
</repository>

pom.xml文件中加入依赖依赖：

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.1.34</version>
</dependency>

使用springmvc的情况下，需要在springmvc.xml中添加配置信息： 

    <!-- 基于Annotation的映射方式 -->  
    <mvc:annotation-driven >  
         <mvc:message-converters register-defaults="true">  
            <bean class="org.springframework.http.converter.StringHttpMessageConverter">  
                <constructor-arg value="UTF-8" />  
            </bean>  
            <!-- <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">  
                 <property name="supportedMediaTypes">  
                    <list>  
                        <value>text/html;charset=UTF-8</value>  
                    </list>  
                </property>  
            </bean> -->  
            <bean class="com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter">    
                <property name="supportedMediaTypes" value="text/html;charset=UTF-8"/>    
                <property name="features">    
                    <array>    
                        <value>WriteMapNullValue</value>    
                        <value>WriteNullStringAsEmpty</value>    
                    </array>    
                </property>    
           </bean>  
        </mvc:message-converters>  
    </mvc:annotation-driven>  

测试类：

public class User {
    private Long id;
    private String name;

    public Long getId() { return id; }
    public void setId(Long id) { this.id = id; }

    public String getName() { return name; }
    public void setName(String name) { this.name = name; }
}
public class Group {
    private Long id;
    private String name;
    private List<User> users = new ArrayList<User>();

    public Long getId() { return id; }
    public void setId(Long id) { this.id = id; }

    public String getName() { return name; }
    public void setName(String name) { this.name = name; }

    public List<User> getUsers() { return users; }
    public void setUsers(List<User> users) { this.users = users; }
}

import com.alibaba.fastjson.JSON;

Group group = new Group();
group.setId(0L);
group.setName("admin");

User guestUser = new User();
guestUser.setId(2L);
guestUser.setName("guest");

User rootUser = new User();
rootUser.setId(3L);
rootUser.setName("root");

group.getUsers().add(guestUser);
group.getUsers().add(rootUser);

String jsonString = JSON.toJSONString(group);
System.out.println(jsonString);

Group group2 = JSON.parseObject(jsonString, Group.class);

SpringMVC中使用：

package com.dx.springlearn.hanlders;

import java.io.IOException;
import java.io.PrintWriter;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.alibaba.fastjson.JSON;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.ModelAndView;

import com.dx.springlearn.entities.Account;
import com.dx.springlearn.entities.WSUserInfo;


@Controller
public class TestModelData {
    private final String SUCCESS = "success";

    @RequestMapping(name = "/postUser", method = RequestMethod.POST)
    public void postUser(String openid, String lng, String lat, HttpServletRequest request,
            HttpServletResponse response) {
        System.out.println("post user..." + openid + "," + lat + "," + lng);

    }

    @RequestMapping(name = "/getUserList", method = RequestMethod.GET)
    public void getUserList(String lng, String lat, HttpServletRequest request, HttpServletResponse response) {
        System.out.println("get user list...." + lat + "," + lng);
        
        List<WSUserInfo> userItems = new ArrayList<>();
        for (int i = 0; i < 10; i++) {
            userItems.add(new WSUserInfo("openid" + i, "120.082" + i, "30.238" + i));
        }

        try {
            //String jsonlist="[{"openid":"openid0","longitude":"120.0820","latitude":"30.2380"},{"openid":"openid1","longitude":"120.0821","latitude":"30.2381"}]";
            String jsonString = JSON.toJSONString(userItems);
            
            PrintWriter out = response.getWriter();
            out.print(jsonString);
            out.flush();
            out.close();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

package com.dx.springlearn.entities;

public class WSUserInfo {
    private String openid;
    private String longitude;
    private String latitude;

    public WSUserInfo(String openid, String longitude, String latitude) {
        super();
        this.openid = openid;
        this.longitude = longitude;
        this.latitude = latitude;
    }

    public String getOpenid() {
        return openid;
    }

    public void setOpenid(String openid) {
        this.openid = openid;
    }

    public String getLongitude() {
        return longitude;
    }

    public void setLongitude(String longitude) {
        this.longitude = longitude;
    }

    public String getLatitude() {
        return latitude;
    }

    public void setLatitude(String latitude) {
        this.latitude = latitude;
    }
}