在Java里面,咱们常用JSON格式的工具包对字符串或者对象进行解析,通常用得比较普遍的三种分别为:fastJson,jackJson,Gson,关于各个工具包的性能比较网络上比比皆是,在这里我只阐述在我本机环境下的测试结果,而后在根据结果对三种工具包进行一个解析,首先先贴代码:java
import java.util.Map; import org.codehaus.jackson.map.ObjectMapper; import com.alibaba.fastjson.JSONObject; import com.google.gson.Gson; public class JsonTest1 { 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 gson=new Gson(); 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 objectMapper = new ObjectMapper(); 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 jsonObject=new JSONObject(); 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 gson=new Gson(); 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 objectMapper = new ObjectMapper(); 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 jsonObject=new JSONObject(); 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; } }
运行结果以下:json
咱们能够看到fastJson的速度明显高于其余两个,真的是这样的吗?咱们把代码在改进一下。安全
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; } }
运行结果以下:网络
看到差别了没?上面的第一部分的代码是每次都要去new新对象出来,在这点上致使了fastJson有绝对的优点,而当咱们初始化的时候就把该准备的资源准备好呢?fastJson的优点一下就体现不出来了,通过屡次测试发现最快的是gson。并且根据上面的结果咱们能够看出来fastJson的优点是在json转化为对象的时候比较快,而对象转化为json格式的字符串的时候性能上是没什么优点的,反而是最差的。app
结论:工具
在作了初始化的状况下GSON的速度都是最快的。性能
在使用GSON或jackJson作Json处理时最好有个全局的解析对象,不要每次调用的时候都去生成那样对性能的影响很大,另外通过测试,这里面没有线程安全问题。测试
fastJson在json转化为对象的应用场景下性能比较突出this
本次的jar版本为:google
fastJson版本为1.1.41
GSON:2.1
O
本文出自 “陈砚羲” 博客,请务必保留此出处http://chenyanxi.blog.51cto.com/4599355/1543445