简介

最近几年，各种新的高效序列化方式层出不穷，不断刷新序列化性能的上限，最典型的包括：

专门针对Java语言的：Kryo，FST等等

跨语言的：Protostuff，ProtoBuf，Thrift，Avro，MsgPack等等

这些序列化方式的性能多数都显著优于hessian2(甚至包括尚未成熟的dubbo序列化)。有鉴于此，我们为dubbo引入Kryo和FST这 两种高效Java序列化实现，来逐步取代hessian2。其中，Kryo是一种非常成熟的序列化实现，已经在Twitter、Groupon、 Yahoo以及多个著名开源项目(如Hive、Storm)中广泛的使用。而FST是一种较新的序列化实现，目前还缺乏足够多的成熟使用案例，但它还是非 常有前途的，下面我们比较下，java原生序列化Kryo序列化性能比较

1、实体类 Simple.java

packagebhz.entity;importjava.io.Serializable;importjava.util.Map;public class Simple implementsSerializable

{private static final long serialVersionUID = -4914434736682797743L;privateString name;private intage;private Mapmap;publicSimple(){

}public Simple(String name,int age,Mapmap){this.name =name;this.age =age;this.map =map;

}publicString getName() {returnname;

}public voidsetName(String name) {this.name =name;

}public intgetAge() {returnage;

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

}public MapgetMap() {returnmap;

}public void setMap(Mapmap) {this.map =map;

}

}

2、java原生序列化 OriginalSerializable.java

packagebhz.test;importjava.io.FileInputStream;importjava.io.FileNotFoundException;importjava.io.FileOutputStream;importjava.io.IOException;importjava.io.ObjectInputStream;importjava.io.ObjectOutputStream;importjava.util.HashMap;importjava.util.Map;importbhz.entity.Simple;public classOriginalSerializable {public static void main(String[] args) throwsIOException, ClassNotFoundException {long start =System.currentTimeMillis();

setSerializableObject();

System.out.println("java原生序列化时间:" + (System.currentTimeMillis() - start) + " ms" );start=System.currentTimeMillis();

getSerializableObject();

System.out.println("java原生反序列化时间:" + (System.currentTimeMillis() - start) + " ms");}public static void setSerializableObject() throwsIOException{

FileOutputStream fo= new FileOutputStream("D:/file2.bin");

ObjectOutputStream so= newObjectOutputStream(fo);for (int i = 0; i < 100000; i++) {

Map map = new HashMap(2);

map.put("zhang0", i);

map.put("zhang1", i);

so.writeObject(new Simple("zhang"+i,(i+1),map));

}

so.flush();

so.close();

}public static voidgetSerializableObject(){

FileInputStream fi;try{

fi= new FileInputStream("D:/file2.bin");

ObjectInputStream si= newObjectInputStream(fi);

Simple simple=null;while((simple=(Simple)si.readObject()) != null){//System.out.println(simple.getAge() + " " + simple.getName());

}

fi.close();

si.close();

}catch(FileNotFoundException e) {

e.printStackTrace();

}catch(IOException e) {//e.printStackTrace();

} catch(ClassNotFoundException e) {

e.printStackTrace();

}

}

}

3、kyro序列化 KyroSerializable.java

packagebhz.test;importjava.io.FileInputStream;importjava.io.FileNotFoundException;importjava.io.FileOutputStream;importjava.io.IOException;importjava.util.HashMap;importjava.util.Map;importorg.objenesis.strategy.StdInstantiatorStrategy;importbhz.entity.Simple;importcom.esotericsoftware.kryo.Kryo;importcom.esotericsoftware.kryo.KryoException;importcom.esotericsoftware.kryo.io.Input;importcom.esotericsoftware.kryo.io.Output;public classKyroSerializable {public static void main(String[] args) throwsIOException {long start =System.currentTimeMillis();

setSerializableObject();

System.out.println("Kryo 序列化时间:" + (System.currentTimeMillis() - start) + " ms");

start=System.currentTimeMillis();

getSerializableObject();

System.out.println("Kryo 反序列化时间:" + (System.currentTimeMillis() - start) + " ms");

}public static void setSerializableObject() throwsFileNotFoundException{

Kryo kryo= newKryo();

kryo.setReferences(false);

kryo.setRegistrationRequired(false);

kryo.setInstantiatorStrategy(newStdInstantiatorStrategy());

kryo.register(Simple.class);

Output output= new Output(new FileOutputStream("D:/file1.bin"));for (int i = 0; i < 100000; i++) {

Map map = new HashMap(2);

map.put("zhang0", i);

map.put("zhang1", i);

kryo.writeObject(output,new Simple("zhang"+i,(i+1),map));

}

output.flush();

output.close();

}public static voidgetSerializableObject(){

Kryo kryo= newKryo();

kryo.setReferences(false);

kryo.setRegistrationRequired(false);

kryo.setInstantiatorStrategy(newStdInstantiatorStrategy());

Input input;try{

input= new Input(new FileInputStream("D:/file1.bin"));

Simple simple=null;while((simple=kryo.readObject(input, Simple.class)) != null){//System.out.println(simple.getAge() + " " + simple.getName() + " " + simple.getMap().toString());

}

input.close();

}catch(FileNotFoundException e) {

e.printStackTrace();

}catch(KryoException e){

}

}

}

4、测试结果对比

java原生序列化时间:8281 ms java原生反序列化时间:5899 ms

和

Kryo 序列化时间:630 ms Kryo 反序列化时间:15 ms

经过对比，可以发现kryo是java原生序列化性能十几倍