关键字:Netty解编码,JBoss Marshalling,
代码在 https://github.com/zhaikaishun/NettyTutorial 在SocketIO_02 kaishun.netty.serial下
Netty解编码技术
解编码技术,说白了就是java序列化技术,序列化的目的就两个,第一进行网络传输,第二对象持久化
虽然我们可以使用java进行对象序列化,netty去传输,但是java序列化的硬伤太多,比如java序列化没法跨语言、序列化够码流太大、序列化性能太低等等…
主流的编码解码框架:
JBoss 的 Marshalling包
google的Protobuf
给予Protobuf的Kyro
MessagePack框架
JBoss Marshalling
Jboss Marshalling是一个java对象序列化包,对jdk默认的序列化框架进行了优化,但又保持跟java.io.Serializable接口的兼容,同时增加了一些可调的参数和附加特性,
类库 jboss-marshalling-1.3.0、jboss-marshalling-serial-1.3.0
Jboss Marshalling与Netty结合后进行序列化对象的代码编写非常简单,我们一起来看一下
首先有个MarshallingCodeCFactory类
这个类不需要看懂,就要有一个这个类就好了
/**
* Marshalling工厂
* @author(alienware)
* @since 2014-12-16
*/
public final class MarshallingCodeCFactory {
/**
* 创建Jboss Marshalling解码器MarshallingDecoder
* @return MarshallingDecoder
*/
public static MarshallingDecoder buildMarshallingDecoder() {
//首先通过Marshalling工具类的精通方法获取Marshalling实例对象 参数serial标识创建的是java序列化工厂对象。
final MarshallerFactory marshallerFactory = Marshalling.getProvidedMarshallerFactory("serial");
//创建了MarshallingConfiguration对象,配置了版本号为5
final MarshallingConfiguration configuration = new MarshallingConfiguration();
configuration.setVersion(5);
//根据marshallerFactory和configuration创建provider
UnmarshallerProvider provider = new DefaultUnmarshallerProvider(marshallerFactory, configuration);
//构建Netty的MarshallingDecoder对象,俩个参数分别为provider和单个消息序列化后的最大长度
MarshallingDecoder decoder = new MarshallingDecoder(provider, 1024 * 1024 * 1);
return decoder;
}
/**
* 创建Jboss Marshalling编码器MarshallingEncoder
* @return MarshallingEncoder
*/
public static MarshallingEncoder buildMarshallingEncoder() {
final MarshallerFactory marshallerFactory = Marshalling.getProvidedMarshallerFactory("serial");
final MarshallingConfiguration configuration = new MarshallingConfiguration();
configuration.setVersion(5);
MarshallerProvider provider = new DefaultMarshallerProvider(marshallerFactory, configuration);
//构建Netty的MarshallingEncoder对象,MarshallingEncoder用于实现序列化接口的POJO对象序列化为二进制数组
MarshallingEncoder encoder = new MarshallingEncoder(provider);
return encoder;
}
}
Server端其他基本不变,就这里
.childHandler(new ChannelInitializer<SocketChannel>() {
protected void initChannel(SocketChannel sc) throws Exception {
sc.pipeline().addLast(MarshallingCodeCFactory.buildMarshallingDecoder());
sc.pipeline().addLast(MarshallingCodeCFactory.buildMarshallingEncoder());
sc.pipeline().addLast(new ServerHandler());
}
});
Client端也是这里有变化
.handler(new ChannelInitializer<SocketChannel>() {
@Override
protected void initChannel(SocketChannel sc) throws Exception {
sc.pipeline().addLast(MarshallingCodeCFactory.buildMarshallingDecoder());
sc.pipeline().addLast(MarshallingCodeCFactory.buildMarshallingEncoder());
sc.pipeline().addLast(new ClientHandler());
}
});
for(int i = 0; i < 5; i++ ){
Req req = new Req();
req.setId("" + i);
req.setName("pro" + i);
req.setRequestMessage("数据信息" + i);
// String path = System.getProperty("user.dir") + File.separatorChar + "sources" + File.separatorChar + "001.jpg";
// File file = new File(path);
// FileInputStream in = new FileInputStream(file);
// byte[] data = new byte[in.available()];
// in.read(data);
// in.close();
// req.setAttachment(GzipUtils.gzip(data));
cf.channel().writeAndFlush(req);
}
Req类
public class Req implements Serializable{
private static final long SerialVersionUID = 1L;
private String id ;
private String name ;
private String requestMessage ;
private byte[] attachment;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getRequestMessage() {
return requestMessage;
}
public void setRequestMessage(String requestMessage) {
this.requestMessage = requestMessage;
}
public byte[] getAttachment() {
return attachment;
}
public void setAttachment(byte[] attachment) {
this.attachment = attachment;
}
}
Resp类
public class Resp implements Serializable{
private static final long serialVersionUID = 1L;
private String id;
private String name;
private String responseMessage;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getResponseMessage() {
return responseMessage;
}
public void setResponseMessage(String responseMessage) {
this.responseMessage = responseMessage;
}
}
ClientHandler
@Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
try {
Resp resp = (Resp)msg;
System.out.println("Client : " + resp.getId() + ", " + resp.getName() + ", " + resp.getResponseMessage());
} finally {
ReferenceCountUtil.release(msg);
}
}
ServerHandler
@Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
Req req = (Req)msg;
System.out.println("Server : " + req.getId() + ", " + req.getName() + ", " + req.getRequestMessage());
// byte[] attachment = GzipUtils.ungzip(req.getAttachment());
//
// String path = System.getProperty("user.dir") + File.separatorChar + "receive" + File.separatorChar + "001.jpg";
// FileOutputStream fos = new FileOutputStream(path);
// fos.write(attachment);
// fos.close();
Resp resp = new Resp();
resp.setId(req.getId());
resp.setName("resp" + req.getId());
resp.setResponseMessage("响应内容" + req.getId());
ctx.writeAndFlush(resp);//.addListener(ChannelFutureListener.CLOSE);
}
总结上面的代码:
其实只需要在Server和Client端加上这两个,其他方法还是一样的。
sc.pipeline().addLast(MarshallingCodeCFactory.buildMarshallingDecoder());
sc.pipeline().addLast(MarshallingCodeCFactory.buildMarshallingEncoder());
补充: 如果还想进行大文件(例如图片视频等传输),将上面的注释的代码打开即可,这块代码还使用了Gzip进行压缩,压缩之后再进行传输,这是需要注意的。
特别感谢互联网架构师白鹤翔老师,本文大多出自他的视频讲解。
笔者主要是记录笔记,以便之后翻阅,正所谓好记性不如烂笔头,烂笔头不如云笔记