第八课 protocol buffer实战

• 1.protocol buff是一种协议，是谷歌推出的一种序列化协议

• 2.Java序列化协议也是一种协议

• 3.两者的目的是，将对象序列化成字节数组，或者说是二进制数据

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java序列化示例

public class JAVA2Bytes {    public static void main(String[] args) throws Exception {        byte[] bytes = toBytes();        toPlayer(bytes);    }    /**     * 序列化     * @throws IOException      */    public static byte[] toBytes() throws IOException{        //新建一个Player类        Player player = new Player(101, 20, "peter");        player.getSkills().add(1001);        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();        ObjectOutputStream objectOutputStream = new ObjectOutputStream(byteArrayOutputStream);        //写入对象        objectOutputStream.writeObject(player);        //获取 字节数组        byte[] byteArray = byteArrayOutputStream.toByteArray();        System.out.println(Arrays.toString(byteArray));        return byteArray;    }    /**     * 反序列化     * @param bs     * @throws Exception      */    public static void toPlayer(byte[] bs) throws Exception{        ObjectInputStream inputStream = new ObjectInputStream(new ByteArrayInputStream(bs));        Player player = (Player)inputStream.readObject();        //打印         System.out.println("playerId:" + player.getPlayerId());         System.out.println("age:" + player.getAge());         System.out.println("name:" + player.getName());         System.out.println("skills:" + (Arrays.toString(player.getSkills().toArray())));    }}

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protocol buffer序列化实例

1 定义要序列化的对象

option java_package = "com.proto";option java_outer_classname = "PlayerModule";message PBPlayer{    required int64 playerId = 1;    required int32 age = 2;    required string name = 3;    repeated int32 skills = 4;}message PBResource{    required int64 gold = 1;    required int32 energy = 2;}

2.使用protoc.exe生成PlayerModule类

3.使用protocol进行序列化

public class PB2Bytes {    public static void main(String[] args) throws Exception {        byte[] bytes = toBytes();        toPlayer(bytes);    }    /**     * 序列化     */    public static byte[] toBytes(){        //获取一个PBPlayer的构造器        Builder builder = PlayerModule.PBPlayer.newBuilder();        //设置数据        builder.setPlayerId(101).setAge(20).setName("jay").addSkills(1001);        //构造出对象        PBPlayer player = builder.build();        //序列化成字节数组        byte[] byteArray = player.toByteArray();        System.out.println("系列化后生成的数组:"+Arrays.toString(byteArray));        return byteArray;    }    /**     * 反序列化     * @param bs     * @throws Exception      */    public static void toPlayer(byte[] bs) throws Exception{         PBPlayer player = PlayerModule.PBPlayer.parseFrom(bs);         System.out.println("playerId:" + player.getPlayerId());         System.out.println("age:" + player.getAge());         System.out.println("name:" + player.getName());         System.out.println("skills:" + (Arrays.toString(player.getSkillsList().toArray())));    }}

根据打印的序列化后的数组可以看出protocol序列化后的数组长度远远小于java自带的序列化方式，因此protocol传输的字节就会少减少带宽消耗。