fastJson,jackJson,Gson 序列化和反序列化实例

直接看实例

import java.util.Map;
import org.codehaus.jackson.map.ObjectMapper;
import com.alibaba.fastjson.JSONObject;
import com.google.gson.Gson;
 
public class JsonTest {
 
    private static ObjectMapper objectMapper = new ObjectMapper();
     
    private static Gson gson=new Gson();
     
    private static JSONObject jsonObject=new JSONObject();
     
 
    private static long count=10000;
    /**
     * @param args
     * @throws Exception 
     */
    public static void main(String[] args) throws Exception {
        // TODO Auto-generated method stub
        gson();
        System.gc();
        jackJson();
        System.gc();
        fastJson();
        System.gc();
        System.out.println("---------------------------------------------------------------");
        gsonJson();
        System.gc();
        jackJsonJson();
        System.gc();
        fastJsonJson();
    }
     
    private static long gson(){
        Demo demo=new Demo();
        demo.setCmd("1");
        demo.setContent("dd");
        long endTime1=System.currentTimeMillis();
         
        for(int i=0;i<count;i++){
            gson.toJson(demo);
        }
        long endTime2=System.currentTimeMillis();
        System.out.println("gson--obj--json:"+(count*1000)/(endTime2-endTime1));
        return endTime2-endTime1;
    }
     
    private static long jackJson() throws Exception{
        Demo demo=new Demo();
        demo.setCmd("1");
        demo.setContent("dd");
        long endTime1=System.currentTimeMillis();
        for(int i=0;i<count;i++){
            objectMapper.writeValueAsString(demo);
        }
        long endTime2=System.currentTimeMillis();
        System.out.println("jackJson--obj--json:"+(count*1000)/(endTime2-endTime1));
        return endTime2-endTime1;
    }
     
     
    private static long fastJson(){
        Demo demo=new Demo();
        demo.setCmd("1");
        demo.setContent("dd");
 
        long endTime1=System.currentTimeMillis();
        for(int i=0;i<count;i++){
            jsonObject.toJSON(demo);
        }
        long endTime2=System.currentTimeMillis();
        System.out.println("fastJson--obj--json:"+(count*1000)/(endTime2-endTime1));
        return endTime2-endTime1;
    }
     
    private static long gsonJson(){
        String json="{\"cmd\":\"1\",\"sss\":\"dd\"}";
         
        long endTime1=System.currentTimeMillis();
         
        for(int i=0;i<count;i++){
           gson.fromJson(json,Map.class);
        }
        long endTime2=System.currentTimeMillis();
        System.out.println("gson--json--obj:"+(count*1000)/(endTime2-endTime1));
        return endTime2-endTime1;
    }
     
    private static long jackJsonJson() throws Exception{
        String json="{\"cmd\":\"1\",\"sss\":\"dd\"}";
     
        long endTime1=System.currentTimeMillis();
        for(int i=0;i<count;i++){
            objectMapper.readValue(json, Map.class);
        }
        long endTime2=System.currentTimeMillis();
        System.out.println("jackJson--json--obj:"+(count*1000)/(endTime2-endTime1));
        return endTime2-endTime1;
    }
     
     
    private static long fastJsonJson(){
        String json="{\"cmd\":\"1\",\"sss\":\"dd\"}";
     
        long endTime1=System.currentTimeMillis();
        for(int i=0;i<count;i++){
            jsonObject.parseObject(json, Map.class);
        }
        long endTime2=System.currentTimeMillis();
        System.out.println("fastJson--json--obj:"+(count*1000)/(endTime2-endTime1));
        return endTime2-endTime1;
    }
 
 
}
 
class Demo {
    private String cmd;
    private String content;
    public String getCmd() {
        return cmd;
    }
    public void setCmd(String cmd) {
        this.cmd = cmd;
    }
    public String getContent() {
        return content;
    }
    public void setContent(String content) {
        this.content = content;
    }
}

总结

把 Java 对象 JSON 序列化，Jackson 速度最快，在测试中比 Gson 快接近 50%，FastJSON 和 Gson 速度接近。

把 JSON 反序列化成 Java 对象，FastJSON、Jackson 速度接近，Gson 速度稍慢，不过差距很小。

参考知乎