Example Depot

package dummypro; import java.io.*; import java.net.*; import java.nio.*; import java.nio.channels.SelectionKey; import java.nio.channels.Selector; import java.nio.channels.ServerSocketChannel; import java.nio.channels.SocketChannel; import java.nio.channels.spi.SelectorProvider; import java.util.HashMap; import java.util.Iterator; import java.util.LinkedList; import java.util.List; import java.util.Map; import NioExample.ChangeRequest; import dummypro.FileServer.FileServerClient; public class Server1 implements Runnable{ private int port=2020; private ServerSocket serversocket; private Socket socket; private String fileName; private ServerSocketChannel serversocketchannel; private SocketChannel socketChannel; private InetSocketAddress socketAddress; private Selector selector; private ByteBuffer readBuffer = ByteBuffer.allocate(8192); private Map pendingData = new HashMap(); private List pendingChanges = new LinkedList(); public Server1() throws IOException { serversocketchannel=ServerSocketChannel.open(); serversocketchannel.configureBlocking(false); this.selector = this.initSelector(); } private void accept(SelectionKey key) throws IOException { // For an accept to be pending the channel must be a server socket channel. ServerSocketChannel serverSocketChannel = (ServerSocketChannel) key.channel(); // Accept the connection and make it non-blocking SocketChannel socketChannel = serverSocketChannel.accept(); socket = socketChannel.socket(); socketChannel.configureBlocking(false); // Register the new SocketChannel with our Selector, indicating // we'd like to be notified when there's data waiting to be read socketChannel.register(this.selector, SelectionKey.OP_READ); System.out.println("Acepted client"); } private Selector initSelector() throws IOException { // Create a new selector Selector socketSelector = SelectorProvider.provider().openSelector(); // Create a new non-blocking server socket channel this.serversocketchannel = ServerSocketChannel.open(); serversocketchannel.configureBlocking(false); // Bind the server socket to the specified address and port socketAddress = new InetSocketAddress(this.port); serversocketchannel.socket().bind(socketAddress); // Register the server socket channel, indicating an interest in // accepting new connections serversocketchannel.register(socketSelector, SelectionKey.OP_ACCEPT); return socketSelector; } private void read(SelectionKey key) throws IOException { SocketChannel socketChannel = (SocketChannel) key.channel(); // Clear out our read buffer so it's ready for new data this.readBuffer.clear(); // Attempt to read off the channel int numRead; try { numRead = socketChannel.read(this.readBuffer); } catch (IOException e) { // The remote forcibly closed the connection, cancel // the selection key and close the channel. key.cancel(); socketChannel.close(); System.out.println("Client losed forcbly"); return; } if (numRead == -1) { // Remote entity shut the socket down cleanly. Do the // same from our end and cancel the channel. key.channel().close(); key.cancel(); System.out.println("Client closed cleanly"); return; } System.out.println("Proessing for response"); } private void write(SelectionKey key) throws IOException { SocketChannel socketChannel = (SocketChannel) key.channel(); synchronized (this.pendingData) { List queue = (List) this.pendingData.get(socketChannel); if(queue.isEmpty()) { System.out.println("Nothing to write"); } // Write until there's not more data ... while (!queue.isEmpty()) { ByteBuffer buf = (ByteBuffer) queue.get(0); socketChannel.write(buf); if (buf.remaining() > 0) { // ... or the socket's buffer fills up break; } queue.remove(0); } System.out.println("Write operation completed"); if (queue.isEmpty()) { // We wrote away all data, so we're no longer interested // in writing on this socket. Switch back to waiting for // data. key.interestOps(SelectionKey.OP_READ); } } } public void run() { while (serversocket != null) { try { Socket client = serversocket.accept(); System.out.println("client = " + client.getInetAddress()); new Thread( new FileServerClient(client) ).start(); } catch (IOException e) { e.printStackTrace(); } } while (true) { try { // Process any pending changes synchronized (this.pendingChanges) { Iterator changes = this.pendingChanges.iterator(); while (changes.hasNext()) { ChangeRequest change = (ChangeRequest) changes.next(); switch (change.type) { case ChangeRequest.CHANGEOPS: SelectionKey key = change.socket.keyFor(this.selector); key.interestOps(change.ops); } } this.pendingChanges.clear(); } // Wait for an event one of the registered channels this.selector.select(); // Iterate over the set of keys for which events are available Iterator selectedKeys = this.selector.selectedKeys().iterator(); while (selectedKeys.hasNext()) { SelectionKey key = (SelectionKey) selectedKeys.next(); selectedKeys.remove(); if (!key.isValid()) { continue; } // Check what event is available and deal with it if (key.isAcceptable()) { this.accept(key); } else if (key.isReadable()) { this.read(key); } else if (key.isWritable()) { this.write(key); } } } catch (Exception e) { e.printStackTrace(); } } } static class FileServerClient implements Runnable { private Socket socket; FileServerClient( Socket s) { socket = s; } public void run() { try { BufferedOutputStream out = new BufferedOutputStream( socket.getOutputStream() ); FileInputStream fileIn = new FileInputStream("C:/Documents and Settings/Admin/workspace/MyProject/src/dummypro/FileServer.txt"); byte[] buffer = new byte[8192]; int bytesRead =0; while ((bytesRead = fileIn.read(buffer)) > 0) { out.write(buffer, 0, bytesRead); } out.flush(); out.close(); fileIn.close(); } catch (IOException e) { e.printStackTrace(); } finally { try { socket.close(); } catch (IOException e) { e.printStackTrace(); } } } } public static void main(String[] args) { String userData=null; BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); System.out.print("Enter your Data: "); try { userData = br.readLine(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } System.out.println("Entered data is "+userData); try { BufferedWriter out = new BufferedWriter(new FileWriter("C:/Documents and Settings/Admin/workspace/MyProject/src/dummypro/FileServer.txt")); out.write(userData); out.close(); } catch (IOException e) { } try { new Thread(new Server1()).start(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }