Introducción a IO no bloqueante y sus ventajas. Como hacer servidores con netty

1. Non-Blocking IO with
Netty
Mariano Cortesi Fernando Zunino
@marianocortesi @fzunino

2. Por que Non Blocking IO?

3. Por que Non Blocking IO?

4. Por que Non Blocking IO?

5. Por que Non Blocking IO?

6. Construyendo servidores
Estructura básica
Leer Decodificar Codificar Enviar
Procesar
Request Request Respuesta Respuesta

7. El Camino Tradicional
✓ Thread por conexión
✓ Uso de IO bloqueante
✓ Modelo sencillo de programación
Leer Decodificar Procesar Codificar Enviar
Cliente
Handler
Cliente Servidor Leer Decodificar Procesar Codificar Enviar
Handler
Cliente
Leer Decodificar Procesar Codificar Enviar
Handler

8. An Echo Server • Java OIO
public class ThreadPoolEchoServer {
public static void main(String[] args) throws IOException {
ServerSocket servSock = new ServerSocket(20007);
Executor service = Executors.newCachedThreadPool();
while (!Thread.interrupted()) {
Socket clntSock = servSock.accept();
service.execute(new EchoWorker(clntSock));
}
}
}

9. An Echo Server • Java OIO
public class ThreadPoolEchoServer { Inicialización de socket
para escucha
public static void main(String[] args) throws IOException {
ServerSocket servSock = new ServerSocket(20007);
Executor service = Executors.newCachedThreadPool();
while (!Thread.interrupted()) {
Socket clntSock = servSock.accept();
service.execute(new EchoWorker(clntSock));
}
}
}

10. An Echo Server • Java OIO
public class ThreadPoolEchoServer {
public static void main(String[] args) throws IOException {
Inicialización de ServerSocket servSock = new ServerSocket(20007);
pool de threads
Executor service = Executors.newCachedThreadPool();
while (!Thread.interrupted()) {
Socket clntSock = servSock.accept();
service.execute(new EchoWorker(clntSock));
}
}
}

11. An Echo Server • Java OIO
public class ThreadPoolEchoServer {
public static void main(String[] args) throws IOException {
ServerSocket servSock = new ServerSocket(20007);
Executor service = Executors.newCachedThreadPool();
while (!Thread.interrupted()) {
Se acepta conexión
Socket clntSock = servSock.accept();
service.execute(new EchoWorker(clntSock));
}
}
}

12. An Echo Server • Java OIO
public class ThreadPoolEchoServer {
public static void main(String[] args) throws IOException {
ServerSocket servSock = new ServerSocket(20007);
Executor service = Executors.newCachedThreadPool();
while (!Thread.interrupted()) {
Socket clntSock = servSock.accept();
service.execute(new EchoWorker(clntSock));
}
}
Se ejecuta worker thread
}

13. An Echo Server • Java OIO
public class ThreadPoolEchoServer {
public static void main(String[] args) throws IOException {
ServerSocket servSock = new ServerSocket(20007);
Executor service = Executors.newCachedThreadPool();
while (!Thread.interrupted()) {
Socket clntSock = servSock.accept();
service.execute(new EchoWorker(clntSock));
}
}
}

14. An Echo Server • Java OIO
public class EchoWorker implements Runnable {
public EchoWorker(final Socket s) {
this.socket = s;
}
public void run() {
try {
InputStream in = this.socket.getInputStream();
OutputStream out = this.socket.getOutputStream();
int recvMsgSize;
byte[] receiveBuf = new byte[256];
while ((recvMsgSize = in.read(receiveBuf)) != -1) {
out.write(receiveBuf, 0, recvMsgSize);
}
} catch (IOException e) { // ...
} finally {
try {
this.socket.close();
} catch (IOException e) { // ... }
}
}
}

15. An Echo Server • Java OIO
public class EchoWorker implements Runnable {
public EchoWorker(final Socket s) {
this.socket = s;
}
Obtención de Streams de
public void run() { entrada y salida
try {
InputStream in = this.socket.getInputStream();
OutputStream out = this.socket.getOutputStream();
int recvMsgSize;
byte[] receiveBuf = new byte[256];
while ((recvMsgSize = in.read(receiveBuf)) != -1) {
out.write(receiveBuf, 0, recvMsgSize);
}
} catch (IOException e) { // ...
} finally {
try {
this.socket.close();
} catch (IOException e) { // ... }
}
}
}

16. An Echo Server • Java OIO
public class EchoWorker implements Runnable {
public EchoWorker(final Socket s) {
this.socket = s;
}
public void run() {
try {
InputStream in = this.socket.getInputStream();
OutputStream out = this.socket.getOutputStream();
int recvMsgSize; Se lee hasta que el
cliente cierre la conexión
byte[] receiveBuf = new byte[256];
(bloqueante)
while ((recvMsgSize = in.read(receiveBuf)) != -1) {
out.write(receiveBuf, 0, recvMsgSize);
}
} catch (IOException e) { // ...
} finally {
try {
this.socket.close();
} catch (IOException e) { // ... }
}
}
}

17. An Echo Server • Java OIO
public class EchoWorker implements Runnable {
public EchoWorker(final Socket s) {
this.socket = s;
}
public void run() {
try {
InputStream in = this.socket.getInputStream();
OutputStream out = this.socket.getOutputStream();
int recvMsgSize;
byte[] receiveBuf = new byte[256];
while ((recvMsgSize = in.read(receiveBuf)) != -1) {
out.write(receiveBuf, 0, recvMsgSize);
}
Se reenvia lo leido al
} catch (IOException e) { // ... cliente (bloqueante)
} finally {
try {
this.socket.close();
} catch (IOException e) { // ... }
}
}
}

18. An Echo Server • Java OIO
public class EchoWorker implements Runnable {
public EchoWorker(final Socket s) {
this.socket = s;
}
public void run() {
try {
InputStream in = this.socket.getInputStream();
OutputStream out = this.socket.getOutputStream();
int recvMsgSize;
byte[] receiveBuf = new byte[256];
while ((recvMsgSize = in.read(receiveBuf)) != -1) {
out.write(receiveBuf, 0, recvMsgSize);
}
} catch (IOException e) { // ...
} finally {
try {
this.socket.close();
} catch (IOException e) { // ... } el socket
Se cierra
}
}
}

19. An Echo Server • Java OIO
public class EchoWorker implements Runnable {
public EchoWorker(final Socket s) {
this.socket = s;
}
public void run() {
try {
InputStream in = this.socket.getInputStream();
OutputStream out = this.socket.getOutputStream();
int recvMsgSize;
byte[] receiveBuf = new byte[256];
while ((recvMsgSize = in.read(receiveBuf)) != -1) {
out.write(receiveBuf, 0, recvMsgSize);
}
} catch (IOException e) { // ...
} finally {
try {
this.socket.close();
} catch (IOException e) { // ... }
}
}
}

20. El Camino Tradicional: Problemas

21. El Camino Tradicional: Problemas
✓ Estado compartido entre clientes

22. El Camino Tradicional: Problemas
✓ Estado compartido entre clientes
✓Sincronización

23. El Camino Tradicional: Problemas
✓ Estado compartido entre clientes
✓Sincronización
✓ Priorización de clientes

24. El Camino Tradicional: Problemas
✓ Estado compartido entre clientes
✓Sincronización
✓ Priorización de clientes
✓ Alta escala (C10K)

25. El Camino Tradicional: Problemas
✓ Estado compartido entre clientes
✓Sincronización
✓ Priorización de clientes
✓ Alta escala (C10K)
✓ Conexiones Persistentes

26. El Camino Tradicional: Problemas
✓ Estado compartido entre clientes
✓Sincronización
✓ Priorización de clientes
✓ Alta escala (C10K)
✓ Conexiones Persistentes
✓ Context Switching Overhead

27. El Camino Tradicional: Problemas
✓ Estado compartido entre clientes
✓Sincronización
✓ Priorización de clientes
✓ Alta escala (C10K)
✓ Conexiones Persistentes
✓ Context Switching Overhead
✓ Consumo de memoria

28. Non Blocking IO: What’s the story?
✓ Modelo orientado a eventos Reactor Pattern
✓ Un único thread de procesamiento
✓ Uso de Readiness Notification y Non Blocking IO
Leer
Cliente
Decodificar
read events
Procesar
Cliente Reactor write events
Codificar
Cliente
Enviar

29. Non Blocking IO vs. Blocking IO

30. Non Blocking IO en Java

31. Non Blocking IO en Java
✓ Java NIO

32. Non Blocking IO en Java
✓ Java NIO
✓ Frameworks

33. Non Blocking IO en Java
✓ Java NIO
✓ Frameworks
✓ Apache Mina

34. Non Blocking IO en Java
✓ Java NIO
✓ Frameworks
✓ Apache Mina
✓ JBoss Netty

35. Non Blocking IO en Java - NIO Diseño
Java NIO
Dispatcher EventHandler
* 1
Selector SelectionKey SelectableChannel
SocketChannel
java.nio.channels

36. An Echo Server • Java NIO
public class Dispatcher {
public Dispatcher(final int port, final EventHandler handler) {
...
}
public void run() throws IOException {
Selector selector = Selector.open();
ServerSocketChannel listenChannel = ServerSocketChannel.open();
listenChannel.socket().bind(new InetSocketAddress(this.port));
listenChannel.configureBlocking(false);
listenChannel.register(selector, SelectionKey.OP_ACCEPT);
while (!Thread.interrupted()) {
if (selector.select(3000) == 0) continue;
Iterator<SelectionKey> keyIter = selector.selectedKeys().iterator();
while (keyIter.hasNext()) {
SelectionKey key = keyIter.next();
if (key.isAcceptable()) {
handler.handleAccept(key);
}
if (key.isReadable()) {
handler.handleRead(key);
}
if (key.isValid() && key.isWritable()) {
handler.handleWrite(key);
}
keyIter.remove(); // remove from set of selected keys
}
}
}
}

37. An Echo Server • Java NIO
public class Dispatcher {
public Dispatcher(final int port, final EventHandler handler) {
...
Crea selector para
}
monitorear sockets
public void run() throws IOException { pasivos y conexiones
Selector selector = Selector.open();
ServerSocketChannel listenChannel = ServerSocketChannel.open();
listenChannel.socket().bind(new InetSocketAddress(this.port));
listenChannel.configureBlocking(false);
listenChannel.register(selector, SelectionKey.OP_ACCEPT);
while (!Thread.interrupted()) {
if (selector.select(3000) == 0) continue;
Iterator<SelectionKey> keyIter = selector.selectedKeys().iterator();
while (keyIter.hasNext()) {
SelectionKey key = keyIter.next();
if (key.isAcceptable()) {
handler.handleAccept(key);
}
if (key.isReadable()) {
handler.handleRead(key);
}
if (key.isValid() && key.isWritable()) {
handler.handleWrite(key);
}
keyIter.remove(); // remove from set of selected keys
}
}
}
}

38. An Echo Server • Java NIO
public class Dispatcher {
public Dispatcher(final int port, final EventHandler handler) {
...
}
public void run() throws IOException { Inicialización de socket
Selector selector = Selector.open(); para escucha en forma no
bloqueante
ServerSocketChannel listenChannel = ServerSocketChannel.open();
listenChannel.socket().bind(new InetSocketAddress(this.port));
listenChannel.configureBlocking(false);
listenChannel.register(selector, SelectionKey.OP_ACCEPT);
while (!Thread.interrupted()) {
if (selector.select(3000) == 0) continue;
Iterator<SelectionKey> keyIter = selector.selectedKeys().iterator();
while (keyIter.hasNext()) {
SelectionKey key = keyIter.next();
if (key.isAcceptable()) {
handler.handleAccept(key);
}
if (key.isReadable()) {
handler.handleRead(key);
}
if (key.isValid() && key.isWritable()) {
handler.handleWrite(key);
}
keyIter.remove(); // remove from set of selected keys
}
}
}
}

39. An Echo Server • Java NIO
public class Dispatcher {
public Dispatcher(final int port, final EventHandler handler) {
...
}
public void run() throws IOException {
Selector selector = Selector.open();
ServerSocketChannel listenChannel = ServerSocketChannel.open();
listenChannel.socket().bind(new InetSocketAddress(this.port));
listenChannel.configureBlocking(false); Registra socket
listenChannel.register(selector, SelectionKey.OP_ACCEPT); declarando interés en
nuevas conexiones
while (!Thread.interrupted()) {
if (selector.select(3000) == 0) continue;
Iterator<SelectionKey> keyIter = selector.selectedKeys().iterator();
while (keyIter.hasNext()) {
SelectionKey key = keyIter.next();
if (key.isAcceptable()) {
handler.handleAccept(key);
}
if (key.isReadable()) {
handler.handleRead(key);
}
if (key.isValid() && key.isWritable()) {
handler.handleWrite(key);
}
keyIter.remove(); // remove from set of selected keys
}
}
}
}

40. An Echo Server • Java NIO
public class Dispatcher {
public Dispatcher(final int port, final EventHandler handler) {
...
}
public void run() throws IOException {
Selector selector = Selector.open();
ServerSocketChannel listenChannel = ServerSocketChannel.open();
listenChannel.socket().bind(new InetSocketAddress(this.port));
Monitorea actividad en
listenChannel.configureBlocking(false);
todos los sockets listenChannel.register(selector, SelectionKey.OP_ACCEPT);
registrados
while (!Thread.interrupted()) {
if (selector.select(3000) == 0) continue;
Iterator<SelectionKey> keyIter = selector.selectedKeys().iterator();
while (keyIter.hasNext()) {
SelectionKey key = keyIter.next();
if (key.isAcceptable()) {
handler.handleAccept(key);
}
if (key.isReadable()) {
handler.handleRead(key);
}
if (key.isValid() && key.isWritable()) {
handler.handleWrite(key);
}
keyIter.remove(); // remove from set of selected keys
}
}
}
}

41. An Echo Server • Java NIO
public class Dispatcher {
public Dispatcher(final int port, final EventHandler handler) {
...
}
public void run() throws IOException {
Selector selector = Selector.open();
ServerSocketChannel listenChannel = ServerSocketChannel.open();
listenChannel.socket().bind(new InetSocketAddress(this.port));
listenChannel.configureBlocking(false);
listenChannel.register(selector, SelectionKey.OP_ACCEPT);
while (!Thread.interrupted()) {
if (selector.select(3000) == 0) continue;
Iterator<SelectionKey> keyIter = selector.selectedKeys().iterator();
while (keyIter.hasNext()) { Detecta y dispara eventos
SelectionKey key = keyIter.next(); de acuerdo al tipo
if (key.isAcceptable()) {
handler.handleAccept(key);
}
if (key.isReadable()) {
handler.handleRead(key);
}
if (key.isValid() && key.isWritable()) {
handler.handleWrite(key);
}
keyIter.remove(); // remove from set of selected keys
}
}
}
}

42. An Echo Server • Java NIO
public class Dispatcher {
public Dispatcher(final int port, final EventHandler handler) {
...
}
public void run() throws IOException {
Selector selector = Selector.open();
ServerSocketChannel listenChannel = ServerSocketChannel.open();
listenChannel.socket().bind(new InetSocketAddress(this.port));
listenChannel.configureBlocking(false);
listenChannel.register(selector, SelectionKey.OP_ACCEPT);
while (!Thread.interrupted()) {
if (selector.select(3000) == 0) continue;
Iterator<SelectionKey> keyIter = selector.selectedKeys().iterator();
while (keyIter.hasNext()) {
SelectionKey key = keyIter.next();
if (key.isAcceptable()) {
handler.handleAccept(key);
}
if (key.isReadable()) {
handler.handleRead(key);
}
if (key.isValid() && key.isWritable()) {
handler.handleWrite(key);
}
keyIter.remove(); // remove from set of selected keys
}
}
}
}

43. An Echo Server • Java NIO
public class EchoProtocolEventHandler implements EventHandler {
private static final int BUFSIZE = 256;
public void handleAccept(SelectionKey key) throws IOException {
SocketChannel clntChan = ((ServerSocketChannel) key.channel()).accept();
clntChan.configureBlocking(false);
clntChan.register(key.selector(), SelectionKey.OP_READ, ByteBuffer.allocate(BUFSIZE));
}
public void handleRead(SelectionKey key) throws IOException {
SocketChannel clntChan = (SocketChannel) key.channel();
ByteBuffer buf = (ByteBuffer) key.attachment();
long bytesRead = clntChan.read(buf);
if (bytesRead == -1) { // Did the other end close?
clntChan.close();
} else if (bytesRead > 0) {
key.interestOps(SelectionKey.OP_READ | SelectionKey.OP_WRITE);
}
}
public void handleWrite(SelectionKey key) throws IOException {
ByteBuffer buf = (ByteBuffer) key.attachment();
buf.flip();
SocketChannel clntChan = (SocketChannel) key.channel();
clntChan.write(buf);
if (!buf.hasRemaining()) {
key.interestOps(SelectionKey.OP_READ);
}
buf.compact();
}
}

44. An Echo Server • Java NIO
public class EchoProtocolEventHandler implements EventHandler {
private static final int BUFSIZE = 256;
Acepta nueva conexión
public void handleAccept(SelectionKey key) throws IOException {
SocketChannel clntChan = ((ServerSocketChannel) key.channel()).accept();
clntChan.configureBlocking(false);
clntChan.register(key.selector(), SelectionKey.OP_READ, ByteBuffer.allocate(BUFSIZE));
}
public void handleRead(SelectionKey key) throws IOException {
SocketChannel clntChan = (SocketChannel) key.channel();
ByteBuffer buf = (ByteBuffer) key.attachment();
long bytesRead = clntChan.read(buf);
if (bytesRead == -1) { // Did the other end close?
clntChan.close();
} else if (bytesRead > 0) {
key.interestOps(SelectionKey.OP_READ | SelectionKey.OP_WRITE);
}
}
public void handleWrite(SelectionKey key) throws IOException {
ByteBuffer buf = (ByteBuffer) key.attachment();
buf.flip();
SocketChannel clntChan = (SocketChannel) key.channel();
clntChan.write(buf);
if (!buf.hasRemaining()) {
key.interestOps(SelectionKey.OP_READ);
}
buf.compact();
}
}

45. An Echo Server • Java NIO
public class EchoProtocolEventHandler implements EventHandler {
private static final int BUFSIZE = 256;
public void handleAccept(SelectionKey key) throws IOException {
SocketChannel clntChan = ((ServerSocketChannel) key.channel()).accept();
clntChan.configureBlocking(false);
clntChan.register(key.selector(), SelectionKey.OP_READ, ByteBuffer.allocate(BUFSIZE));
}
Registra nuevo socket
public void handleRead(SelectionKey key) throws IOException { declarando interés en
SocketChannel clntChan = (SocketChannel) key.channel(); lectura y asocia buffer
ByteBuffer buf = (ByteBuffer) key.attachment();
long bytesRead = clntChan.read(buf);
if (bytesRead == -1) { // Did the other end close?
clntChan.close();
} else if (bytesRead > 0) {
key.interestOps(SelectionKey.OP_READ | SelectionKey.OP_WRITE);
}
}
public void handleWrite(SelectionKey key) throws IOException {
ByteBuffer buf = (ByteBuffer) key.attachment();
buf.flip();
SocketChannel clntChan = (SocketChannel) key.channel();
clntChan.write(buf);
if (!buf.hasRemaining()) {
key.interestOps(SelectionKey.OP_READ);
}
buf.compact();
}
}

46. An Echo Server • Java NIO
public class EchoProtocolEventHandler implements EventHandler {
private static final int BUFSIZE = 256;
public void handleAccept(SelectionKey key) throws IOException {
SocketChannel clntChan = ((ServerSocketChannel) key.channel()).accept();
clntChan.configureBlocking(false);
clntChan.register(key.selector(), SelectionKey.OP_READ, ByteBuffer.allocate(BUFSIZE));
}
public void handleRead(SelectionKey key) throws IOException {
SocketChannel clntChan = (SocketChannel) key.channel();
ByteBuffer buf = (ByteBuffer) key.attachment();
long bytesRead = clntChan.read(buf); Lee datos en buffer
if (bytesRead == -1) { // Did the other end close? asociado
clntChan.close();
} else if (bytesRead > 0) {
key.interestOps(SelectionKey.OP_READ | SelectionKey.OP_WRITE);
}
}
public void handleWrite(SelectionKey key) throws IOException {
ByteBuffer buf = (ByteBuffer) key.attachment();
buf.flip();
SocketChannel clntChan = (SocketChannel) key.channel();
clntChan.write(buf);
if (!buf.hasRemaining()) {
key.interestOps(SelectionKey.OP_READ);
}
buf.compact();
}
}

47. An Echo Server • Java NIO
public class EchoProtocolEventHandler implements EventHandler {
private static final int BUFSIZE = 256;
public void handleAccept(SelectionKey key) throws IOException {
SocketChannel clntChan = ((ServerSocketChannel) key.channel()).accept();
clntChan.configureBlocking(false);
clntChan.register(key.selector(), SelectionKey.OP_READ, ByteBuffer.allocate(BUFSIZE));
}
public void handleRead(SelectionKey key) throws IOException {
SocketChannel clntChan = (SocketChannel) key.channel();
ByteBuffer buf = (ByteBuffer) key.attachment();
long bytesRead = clntChan.read(buf);
if (bytesRead == -1) { // Did the other end close?
clntChan.close();
} else if (bytesRead > 0) {
key.interestOps(SelectionKey.OP_READ | SelectionKey.OP_WRITE); Detecta fin de conexión
}
}
public void handleWrite(SelectionKey key) throws IOException {
ByteBuffer buf = (ByteBuffer) key.attachment();
buf.flip();
SocketChannel clntChan = (SocketChannel) key.channel();
clntChan.write(buf);
if (!buf.hasRemaining()) {
key.interestOps(SelectionKey.OP_READ);
}
buf.compact();
}
}

48. An Echo Server • Java NIO
public class EchoProtocolEventHandler implements EventHandler {
private static final int BUFSIZE = 256;
public void handleAccept(SelectionKey key) throws IOException {
SocketChannel clntChan = ((ServerSocketChannel) key.channel()).accept();
clntChan.configureBlocking(false);
clntChan.register(key.selector(), SelectionKey.OP_READ, ByteBuffer.allocate(BUFSIZE));
}
public void handleRead(SelectionKey key) throws IOException {
SocketChannel clntChan = (SocketChannel) key.channel();
ByteBuffer buf = (ByteBuffer) key.attachment();
long bytesRead = clntChan.read(buf);
if (bytesRead == -1) { // Did the other end close?
clntChan.close();
} else if (bytesRead > 0) {
key.interestOps(SelectionKey.OP_READ | SelectionKey.OP_WRITE);
}
}
Declara interés en
public void handleWrite(SelectionKey key) throws IOException { escritura si hay datos a
ByteBuffer buf = (ByteBuffer) key.attachment(); escribir
buf.flip();
SocketChannel clntChan = (SocketChannel) key.channel();
clntChan.write(buf);
if (!buf.hasRemaining()) {
key.interestOps(SelectionKey.OP_READ);
}
buf.compact();
}
}

49. An Echo Server • Java NIO
public class EchoProtocolEventHandler implements EventHandler {
private static final int BUFSIZE = 256;
public void handleAccept(SelectionKey key) throws IOException {
SocketChannel clntChan = ((ServerSocketChannel) key.channel()).accept();
clntChan.configureBlocking(false);
clntChan.register(key.selector(), SelectionKey.OP_READ, ByteBuffer.allocate(BUFSIZE));
}
public void handleRead(SelectionKey key) throws IOException {
SocketChannel clntChan = (SocketChannel) key.channel();
ByteBuffer buf = (ByteBuffer) key.attachment();
long bytesRead = clntChan.read(buf);
if (bytesRead == -1) { // Did the other end close?
clntChan.close();
} else if (bytesRead > 0) {
key.interestOps(SelectionKey.OP_READ | SelectionKey.OP_WRITE);
}
}
public void handleWrite(SelectionKey key) throws IOException {
ByteBuffer buf = (ByteBuffer) key.attachment();
buf.flip();
SocketChannel clntChan = (SocketChannel) key.channel();
clntChan.write(buf); Envia datos al socket
if (!buf.hasRemaining()) {
key.interestOps(SelectionKey.OP_READ);
}
buf.compact();
}
}

50. An Echo Server • Java NIO
public class EchoProtocolEventHandler implements EventHandler {
private static final int BUFSIZE = 256;
public void handleAccept(SelectionKey key) throws IOException {
SocketChannel clntChan = ((ServerSocketChannel) key.channel()).accept();
clntChan.configureBlocking(false);
clntChan.register(key.selector(), SelectionKey.OP_READ, ByteBuffer.allocate(BUFSIZE));
}
public void handleRead(SelectionKey key) throws IOException {
SocketChannel clntChan = (SocketChannel) key.channel();
ByteBuffer buf = (ByteBuffer) key.attachment();
long bytesRead = clntChan.read(buf);
if (bytesRead == -1) { // Did the other end close?
clntChan.close();
} else if (bytesRead > 0) {
key.interestOps(SelectionKey.OP_READ | SelectionKey.OP_WRITE);
}
}
public void handleWrite(SelectionKey key) throws IOException {
ByteBuffer buf = (ByteBuffer) key.attachment();
buf.flip();
SocketChannel clntChan = (SocketChannel) key.channel();
clntChan.write(buf);
if (!buf.hasRemaining()) {
key.interestOps(SelectionKey.OP_READ);
} Revoca interés en escritura
buf.compact(); si no hay nada para escribir
}
}

51. An Echo Server • Java NIO
public class EchoProtocolEventHandler implements EventHandler {
private static final int BUFSIZE = 256;
public void handleAccept(SelectionKey key) throws IOException {
SocketChannel clntChan = ((ServerSocketChannel) key.channel()).accept();
clntChan.configureBlocking(false);
clntChan.register(key.selector(), SelectionKey.OP_READ, ByteBuffer.allocate(BUFSIZE));
}
public void handleRead(SelectionKey key) throws IOException {
SocketChannel clntChan = (SocketChannel) key.channel();
ByteBuffer buf = (ByteBuffer) key.attachment();
long bytesRead = clntChan.read(buf);
if (bytesRead == -1) { // Did the other end close?
clntChan.close();
} else if (bytesRead > 0) {
key.interestOps(SelectionKey.OP_READ | SelectionKey.OP_WRITE);
}
}
public void handleWrite(SelectionKey key) throws IOException {
ByteBuffer buf = (ByteBuffer) key.attachment();
buf.flip();
SocketChannel clntChan = (SocketChannel) key.channel();
clntChan.write(buf);
if (!buf.hasRemaining()) {
key.interestOps(SelectionKey.OP_READ);
}
buf.compact();
}
}

52. An Echo Server • Java NIO
public interface EventHandler {
void handleAccept(SelectionKey key) throws IOException;
void handleRead(SelectionKey key) throws IOException;
void handleWrite(SelectionKey key) throws IOException;
}
public class NIOEchoServer {
public static void main(String[] args) throws IOException {
Dispatcher dispatcher = new Dispatcher(20007,
new EchoProtocolEventHandler());
dispatcher.run();
}
}

53. Netty!!
from Netty Homepage
The Netty project is an effort to provide an
asynchronous event-driven network application
framework and tools for rapid development of
maintainable high performance & high scalability
protocol servers & clients

54. Netty!!
from Netty Homepage
The Netty project is an effort to provide an
asynchronous event-driven network application
framework and tools for rapid development of
maintainable high performance & high scalability
protocol servers & clients

55. Netty!!
from Netty Homepage
The Netty project is an effort to provide an
asynchronous event-driven application
network
framework and tools for rapid development of
maintainable high performance & high scalability
protocol servers & clients

56. Netty!!
from Netty Homepage
The Netty project is an effort to provide an
asynchronous event-driven network application
framework and tools for rapid development of
high performance & high scalability
maintainable
protocol servers & clients

57. Netty!!
from Netty Homepage
The Netty project is an effort to provide an
asynchronous event-driven network application
rapid development
framework and tools for of
maintainable high performance & high scalability
protocol servers & clients

58. Netty!!
from Netty Homepage
The Netty project is an effort to provide an
asynchronous event-driven network application
framework and tools for rapid development of
maintainable high performance & high scalability
protocol servers & clients
Warning! Netty no es un WebServer

59. Netty Model • Channels
creates handles
ChannelFactory Channel ChannelPipeline
es with
& writ generates is sorted list of
s
read
handles
ChannelBuffer ChannelEvent ChannelHandler
✓ Representa a una conexion P2P (point to point)
✓ Abstrae UDP / TCP
✓ Abstrae NIO / OIO
✓ API interacción conexión (abrir, cerrar, escribir, leer)

60. Netty Model • ChannelBuffers
creates handles
ChannelFactory Channel ChannelPipeline
es with
& writ generates is sorted list of
s
read
handles
ChannelBuffer ChannelEvent ChannelHandler

61. Netty Model • ChannelBuffers
creates handles
ChannelFactory Channel ChannelPipeline
es with
& writ generates is sorted list of
s
read
handles
ChannelBuffer ChannelEvent ChannelHandler
✓ Abstrae de NIO Buffers & byte arrays
✓ API simplificada respecto NIO Buffers
✓ Toda lectura y escritura se hace con ellos

62. Netty Model • ChannelFactory
creates handles
ChannelFactory Channel ChannelPipeline
es with
& writ generates is sorted list of
s
read
handles
ChannelBuffer ChannelEvent ChannelHandler

63. Netty Model • ChannelFactory
creates handles
ChannelFactory Channel ChannelPipeline
es with
& writ generates is sorted list of
s
read
handles
ChannelBuffer ChannelEvent ChannelHandler
✓ Crear Channels
✓ ChannelFactory impl. para UDP / TCP y OIO / NIO
✓ Non Blocking con: NioServerSocketChannelFactory

64. Netty Model • ChannelEvent
creates handles
ChannelFactory Channel ChannelPipeline
es with
& writ generates is sorted list of
s
read
handles
ChannelBuffer ChannelEvent ChannelHandler

65. Netty Model • ChannelEvent
creates handles
ChannelFactory Channel ChannelPipeline
es with
& writ generates is sorted list of
s
read
handles
ChannelBuffer ChannelEvent ChannelHandler
✓ Representa un evento I/O asociado a un Channel
✓ Puede ser upstream (entrada) or downstream (salida)
✓ Se pueden crear eventos custom
✓ Algunos tipos de evento:
★ messageReceived
★ channelOpen
★ channelClosed
★ write

66. Netty Model • ChannelPipeline
creates handles
ChannelFactory Channel ChannelPipeline
es with
& writ generates is sorted list of
s
read
handles
ChannelBuffer ChannelEvent ChannelHandler

67. Netty Model • ChannelPipeline
creates handles
ChannelFactory Channel ChannelPipeline
es with
& writ generates is sorted list of
s
read
handles
ChannelBuffer ChannelEvent ChannelHandler
✓ Asociado a un Channel
✓ Atrapa y Handlea los ChannelEvents
✓ Implementa el patron Intercepting Filter

68. Netty Model • ChannelHandler
creates handles
ChannelFactory Channel ChannelPipeline
es with
& writ generates is sorted list of
s
read
handles
ChannelBuffer ChannelEvent ChannelHandler

69. Netty Model • ChannelHandler
creates handles
ChannelFactory Channel ChannelPipeline
es with
& writ generates is sorted list of
s
read
handles
ChannelBuffer ChannelEvent ChannelHandler
✓ Building block de un ChannelPipeline
✓ Handlea ChannelEvents (upstream y/o downstream)
✓ Decide sobre el forwarding de eventos a sus pares
upstream
Handler
Handler
Handler
Handler
event
N -1
First
Last
2nd
downstream
event

70. An Echo Server • Netty NIO
Main Class
public class EchoServer {
public static void main(String[] args) throws Exception {
// Configure the server.
ServerBootstrap bootstrap = new ServerBootstrap(
new NioServerSocketChannelFactory(
Executors.newCachedThreadPool(),
Executors.newCachedThreadPool()));
// Set up the pipeline factory.
bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
public ChannelPipeline getPipeline() throws Exception {
return Channels.pipeline(new EchoServerHandler());
}
});
// Bind and start to accept incoming connections.
bootstrap.bind(new InetSocketAddress(8080));
}
}
Ejemplo en: http://docs.jboss.org/netty/3.2/xref/org/jboss/netty/example/echo/package-summary.html

71. An Echo Server • Netty NIO
Main Class
public class EchoServer {
Utility Class para
public static void main(String[] args) throws Exception {inicializar un Server
// Configure the server.
ServerBootstrap bootstrap = new ServerBootstrap(
new NioServerSocketChannelFactory(
Executors.newCachedThreadPool(),
Executors.newCachedThreadPool()));
// Set up the pipeline factory.
bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
public ChannelPipeline getPipeline() throws Exception {
return Channels.pipeline(new EchoServerHandler());
}
});
// Bind and start to accept incoming connections.
bootstrap.bind(new InetSocketAddress(8080));
}
}
Ejemplo en: http://docs.jboss.org/netty/3.2/xref/org/jboss/netty/example/echo/package-summary.html

72. An Echo Server • Netty NIO
Main Class
public class EchoServer {
public static void main(String[] args) throws Exception {
// Configure the server.
ServerBootstrap bootstrap = new ServerBootstrap(
ChannelFactory para Tcp
new NioServerSocketChannelFactory(
w/ NIO
Executors.newCachedThreadPool(),
Executors.newCachedThreadPool()));
// Set up the pipeline factory.
bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
public ChannelPipeline getPipeline() throws Exception {
return Channels.pipeline(new EchoServerHandler());
}
});
// Bind and start to accept incoming connections.
bootstrap.bind(new InetSocketAddress(8080));
}
}
Ejemplo en: http://docs.jboss.org/netty/3.2/xref/org/jboss/netty/example/echo/package-summary.html

73. An Echo Server • Netty NIO
Main Class
public class EchoServer {
public static void main(String[] args) throws Exception {
// Configure the server.
Boss pool thread
ServerBootstrap bootstrap = new ServerBootstrap(
new NioServerSocketChannelFactory(
Executors.newCachedThreadPool(),
Executors.newCachedThreadPool()));
Workers pool thread
// Set up the pipeline factory.
bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
public ChannelPipeline getPipeline() throws Exception {
return Channels.pipeline(new EchoServerHandler());
}
});
// Bind and start to accept incoming connections.
bootstrap.bind(new InetSocketAddress(8080));
}
}
Ejemplo en: http://docs.jboss.org/netty/3.2/xref/org/jboss/netty/example/echo/package-summary.html

74. An Echo Server • Netty NIO
Main Class
public class EchoServer {
public static void main(String[] args) throws Exception {
// Configure the server.
ServerBootstrap bootstrap = new ServerBootstrap(
new NioServerSocketChannelFactory(
Executors.newCachedThreadPool(),
Executors.newCachedThreadPool()));
// Set up the pipeline factory.
bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
public ChannelPipeline getPipeline() throws Exception {
ChannelPipelineFactory
para cada nuevo Channel return Channels.pipeline(new EchoServerHandler());
establcido }
});
// Bind and start to accept incoming connections.
bootstrap.bind(new InetSocketAddress(8080));
}
}
Ejemplo en: http://docs.jboss.org/netty/3.2/xref/org/jboss/netty/example/echo/package-summary.html

75. An Echo Server • Netty NIO
Main Class
public class EchoServer {
public static void main(String[] args) throws Exception {
// Configure the server.
ServerBootstrap bootstrap = new ServerBootstrap(
new NioServerSocketChannelFactory(
Executors.newCachedThreadPool(),
Executors.newCachedThreadPool()));
// Set up the pipeline factory.
bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
public ChannelPipeline getPipeline() throws Exception {
return Channels.pipeline(new EchoServerHandler());
}
});
Un solo handler. El echo
Handler
// Bind and start to accept incoming connections.
bootstrap.bind(new InetSocketAddress(8080));
}
}
Ejemplo en: http://docs.jboss.org/netty/3.2/xref/org/jboss/netty/example/echo/package-summary.html

76. An Echo Server • Netty NIO
Main Class
public class EchoServer {
public static void main(String[] args) throws Exception {
// Configure the server.
ServerBootstrap bootstrap = new ServerBootstrap(
new NioServerSocketChannelFactory(
Executors.newCachedThreadPool(),
Executors.newCachedThreadPool()));
// Set up the pipeline factory.
bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
public ChannelPipeline getPipeline() throws Exception {
return Channels.pipeline(new EchoServerHandler());
}
});
// Bind and start to accept incoming connections.
bootstrap.bind(new InetSocketAddress(8080));
}
} Finalmente inicializamos
el servidor
Ejemplo en: http://docs.jboss.org/netty/3.2/xref/org/jboss/netty/example/echo/package-summary.html

77. An Echo Server • Netty NIO
Handler
public class EchoServerHandler extends SimpleChannelHandler {
@Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
e.getChannel().write(e.getMessage());
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) {
e.getCause().printStackTrace();
Channel ch = e.getChannel();
ch.close();
}
}
Ejemplo en: http://docs.jboss.org/netty/3.2/xref/org/jboss/netty/example/echo/package-summary.html

78. An Echo Server • Netty NIO
Handler
Utility class para handlear
public class EchoServerHandler extends SimpleChannelHandler { eventos típicos
@Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
e.getChannel().write(e.getMessage());
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) {
e.getCause().printStackTrace();
Channel ch = e.getChannel();
ch.close();
}
}
Ejemplo en: http://docs.jboss.org/netty/3.2/xref/org/jboss/netty/example/echo/package-summary.html

79. An Echo Server • Netty NIO
Handler
public class EchoServerHandler extends SimpleChannelHandler {
@Override
Event Handler para
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
nuevo mensaje
e.getChannel().write(e.getMessage());
}
@Override
Event Handler para void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) {
public
excepciones
e.getCause().printStackTrace();
Channel ch = e.getChannel();
ch.close();
}
}
Ejemplo en: http://docs.jboss.org/netty/3.2/xref/org/jboss/netty/example/echo/package-summary.html

80. An Echo Server • Netty NIO
Handler
public class EchoServerHandler extends SimpleChannelHandler {
@Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
e.getChannel().write(e.getMessage());
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) {
e.getCause().printStackTrace();
Contexto del Canal
Channel ch = e.getChannel(); Permite interactuar con su
ch.close(); pipeline
}
}
Ejemplo en: http://docs.jboss.org/netty/3.2/xref/org/jboss/netty/example/echo/package-summary.html

81. An Echo Server • Netty NIO
Handler
public class EchoServerHandler extends SimpleChannelHandler {
@Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
e.getChannel().write(e.getMessage());
} Interacción con el Channel:
Lectura y Escritura
@Override
public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) {
e.getCause().printStackTrace();
Channel ch = e.getChannel();
ch.close();
}
}
Ejemplo en: http://docs.jboss.org/netty/3.2/xref/org/jboss/netty/example/echo/package-summary.html

82. An Echo Server • Netty OIO
Vuelta a OIO!
public class EchoServer {
public static void main(String[] args) throws Exception {
// Configure the server.
ServerBootstrap bootstrap = new ServerBootstrap(
new OioServerSocketChannelFactory(
Executors.newCachedThreadPool(),
Executors.newCachedThreadPool()));
// Set up the pipeline factory.
bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
public ChannelPipeline getPipeline() throws Exception {
return Channels.pipeline(new EchoServerHandler());
}
});
// Bind and start to accept incoming connections.
bootstrap.bind(new InetSocketAddress(8080));
}
}

83. An Echo Server • Netty OIO
Vuelta a OIO!
public class EchoServer {
public static void main(String[] args) throws Exception {
// Configure the server.
ServerBootstrap bootstrap = new ServerBootstrap(
ChannelFactory para Tcp
new OioServerSocketChannelFactory(
w/ OIO
Executors.newCachedThreadPool(),
Executors.newCachedThreadPool()));
// Set up the pipeline factory.
bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
public ChannelPipeline getPipeline() throws Exception {
return Channels.pipeline(new EchoServerHandler());
}
});
// Bind and start to accept incoming connections.
bootstrap.bind(new InetSocketAddress(8080));
}
}

84. A Distributed Logger • Diseño
Protocolo
✓ Formato textual, de linea
✓ Paquete tamaño variable
✓ Mensaje por fin de linea
✓ Formato: “${level} - ${mensaje}”
DEBUG - Algo esta mal!!

85. Framer Handler
Decoder Handler
pipeline
LoggerPrinter
Handler
A Distributed Logger • Diseño

86. Framer Handler
Decoder Handler
LoggerPrinter
Handler
A Distributed Logger • Framer

87. A Distributed Logger • Framer
Decoder Handler
Framer Handler
LoggerPrinter
Handler
Framer
import org.jboss.netty.handler.codec.frame.DelimiterBasedFrameDecoder;
import org.jboss.netty.handler.codec.frame.Delimiters;
public class LoggerFramerHandler extends DelimiterBasedFrameDecoder {
public LoggerFramerHandler() {
super(8000, Delimiters.lineDelimiter());
}
}

88. A Distributed Logger • Framer
Decoder Handler
Framer Handler
LoggerPrinter
Handler
Framer
import org.jboss.netty.handler.codec.frame.DelimiterBasedFrameDecoder;
import org.jboss.netty.handler.codec.frame.Delimiters;
public class LoggerFramerHandler extends DelimiterBasedFrameDecoder {
public LoggerFramerHandler() { Framer para demarcar
super(8000, Delimiters.lineDelimiter()); paquetes a través de un
} delimitador
}

89. A Distributed Logger • Framer
Decoder Handler
Framer Handler
LoggerPrinter
Handler
Framer
import org.jboss.netty.handler.codec.frame.DelimiterBasedFrameDecoder;
import org.jboss.netty.handler.codec.frame.Delimiters;
public class LoggerFramerHandler extends DelimiterBasedFrameDecoder {
public LoggerFramerHandler() {
super(8000, Delimiters.lineDelimiter());
}
} Delimitador para lineas

90. Framer Handler
Decoder Handler
LoggerPrinter
Handler
A Distributed Logger • Framer

91. Framer Handler
Decoder Handler
LoggerPrinter
Handler
A Distributed Logger • Decoder

92. A Distributed Logger • Decoder
Decoder Handler
Framer Handler
LoggerPrinter
Handler
Decoder
@Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
Charset ch = Charset.defaultCharset();
String msg = ((ChannelBuffer) e.getMessage()).toString(ch);
String[] args = msg.split("-", 2);
LogEvent logEvent = new LogEvent(Level.valueOf(args[0].trim()),
args[1].trim());
Channels.fireMessageReceived(ctx, logEvent);
}

93. A Distributed Logger • Decoder
Decoder Handler
Framer Handler
LoggerPrinter
Handler
Decoder
@Override El framer deja un
public void messageReceived(ChannelHandlerContext ctx, MessageEventmsg {
ChannelBuffer como e)
Charset ch = Charset.defaultCharset();
String msg = ((ChannelBuffer) e.getMessage()).toString(ch);
String[] args = msg.split("-", 2);
LogEvent logEvent = new LogEvent(Level.valueOf(args[0].trim()),
args[1].trim());
Channels.fireMessageReceived(ctx, logEvent);
}

94. A Distributed Logger • Decoder
Decoder Handler
Framer Handler
LoggerPrinter
Handler
Decoder
@Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
Charset ch = Charset.defaultCharset();
String msg = ((ChannelBuffer) e.getMessage()).toString(ch);
String[] args = msg.split("-", 2); parseo y creación de un
LogEvent
LogEvent logEvent = new LogEvent(Level.valueOf(args[0].trim()),
args[1].trim());
Channels.fireMessageReceived(ctx, logEvent);
}

95. A Distributed Logger • Decoder
Decoder Handler
Framer Handler
LoggerPrinter
Handler
Decoder
@Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
Charset ch = Charset.defaultCharset();
String msg = ((ChannelBuffer) e.getMessage()).toString(ch);
String[] args = msg.split("-", 2);
LogEvent logEvent = new LogEvent(Level.valueOf(args[0].trim()),
args[1].trim());
Channels.fireMessageReceived(ctx, logEvent);
}
propago el mensaje, como
LogEvent

96. Framer Handler
Decoder Handler
LoggerPrinter
Handler
A Distributed Logger • Decoder

97. Framer Handler
Decoder Handler
LoggerPrinter
Handler
A Distributed Logger • Printer

98. A Distributed Logger • Printer
Decoder Handler
Framer Handler
LoggerPrinter
Handler
Printer
@Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
LogEvent logEvent = (LogEvent) e.getMessage();
System.out.println(logEvent);
}

99. A Distributed Logger • Printer
Decoder Handler
Framer Handler
LoggerPrinter
Handler
Printer
El msg ahora es un
@Override LogEvent
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
LogEvent logEvent = (LogEvent) e.getMessage();
System.out.println(logEvent);
}

100. A Distributed Logger • Printer
Decoder Handler
Framer Handler
LoggerPrinter
Handler
Printer
@Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
LogEvent logEvent = (LogEvent) e.getMessage();
System.out.println(logEvent);
}

101. Conclusiones
✓ Non-Blocking IO
✓ Importa!
✓ Aplicaciones altamente concurrentes
(c10k)
✓ Netty
✓ java nio made easy
✓ modelo flexible para crear servidores
NIO (o OIO)

102. ¿¿ Preguntas ??
We are hiring! Apply at jobs@zaubersoftware.com