Refactored the local port forwarding API; give caller control over initializing and cleaning up the server socket used.

Also removed 'server socket factory' stuff from SocketClient.

src/main/java/examples/LocalPF.java

@@ -16,9 +16,11 @@
 package examples;
 
 import net.schmizz.sshj.SSHClient;
+import net.schmizz.sshj.connection.channel.direct.LocalPortForwarder;
 
 import java.io.IOException;
 import java.net.InetSocketAddress;
+import java.net.ServerSocket;
 
 /**
  * This example demonstrates local port forwarding, i.e. when we listen on a particular address and port; and forward
@@ -41,8 +43,16 @@ public class LocalPF {
             * _We_ listen on localhost:8080 and forward all connections on to server, which then forwards it to
             * google.com:80
             */
-            ssh.newLocalPortForwarder(new InetSocketAddress("localhost", 8080), "google.com", 80)
-               .listen();
+            final LocalPortForwarder.Parameters params
+                    = new LocalPortForwarder.Parameters("0.0.0.0", 8080, "google.com", 80);
+            final ServerSocket ss = new ServerSocket();
+            ss.setReuseAddress(true);
+            ss.bind(new InetSocketAddress(params.getLocalHost(), params.getLocalPort()));
+            try {
+                ssh.newLocalPortForwarder(params, ss).listen();
+            } finally {
+                ss.close();
+            }
 
         } finally {
             ssh.disconnect();

src/main/java/net/schmizz/sshj/SSHClient.java

@@ -64,7 +64,7 @@ import org.slf4j.LoggerFactory;
 import java.io.Closeable;
 import java.io.File;
 import java.io.IOException;
-import java.net.SocketAddress;
+import java.net.ServerSocket;
 import java.security.KeyPair;
 import java.security.PublicKey;
 import java.util.Arrays;
@@ -568,23 +568,21 @@ public class SSHClient
     }
 
     /**
-     * Create a {@link LocalPortForwarder} that will listen on {@code address} and forward incoming connections to the
-     * server; which will further forward them to {@code host:port}.
+     * Create a {@link LocalPortForwarder} that will listen based on {@code parameters} using the bound
+     * {@code serverSocket} and forward incoming connections to the server; which will further forward them to
+     * {@code host:port}.
      * <p/>
      * The returned forwarder's {@link LocalPortForwarder#listen() listen()} method should be called to actually start
      * listening, this method just creates an instance.
      *
-     * @param address defines where the {@link LocalPortForwarder} listens
-     * @param host    hostname to which the server will forward
-     * @param port    the port at {@code hostname} to which the server wil forward
+     * @param parameters   parameters for the forwarding setup
+     * @param serverSocket bound server socket
      *
      * @return a {@link LocalPortForwarder}
-     *
-     * @throws IOException if there is an error opening a local server socket
      */
-    public LocalPortForwarder newLocalPortForwarder(SocketAddress address, String host, int port)
-            throws IOException {
-        return new LocalPortForwarder(getServerSocketFactory(), conn, address, host, port);
+    public LocalPortForwarder newLocalPortForwarder(LocalPortForwarder.Parameters parameters,
+                                                    ServerSocket serverSocket) {
+        return new LocalPortForwarder(conn, parameters, serverSocket);
     }
 
     /**

src/main/java/net/schmizz/sshj/SocketClient.java

@@ -35,6 +35,7 @@
  */
 package net.schmizz.sshj;
 
+import javax.net.SocketFactory;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
@@ -42,10 +43,6 @@ import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.Socket;
 
-import javax.net.ServerSocketFactory;
-import javax.net.SocketFactory;
-
-
 public abstract class SocketClient {
 
     private final int defaultPort;
@@ -55,7 +52,6 @@ public abstract class SocketClient {
     private OutputStream output;
 
     private SocketFactory socketFactory = SocketFactory.getDefault();
-    private ServerSocketFactory serverSocketFactory = ServerSocketFactory.getDefault();
 
     private static final int DEFAULT_CONNECT_TIMEOUT = 0;
     private int connectTimeout = DEFAULT_CONNECT_TIMEOUT;
@@ -159,17 +155,6 @@ public abstract class SocketClient {
         return socketFactory;
     }
 
-    public void setServerSocketFactory(ServerSocketFactory factory) {
-        if (factory == null)
-            serverSocketFactory = ServerSocketFactory.getDefault();
-        else
-            serverSocketFactory = factory;
-    }
-
-    public ServerSocketFactory getServerSocketFactory() {
-        return serverSocketFactory;
-    }
-
     public int getConnectTimeout() {
         return connectTimeout;
     }

src/main/java/net/schmizz/sshj/connection/channel/direct/LocalPortForwarder.java

@@ -19,104 +19,104 @@ import net.schmizz.concurrent.Event;
 import net.schmizz.sshj.common.SSHPacket;
 import net.schmizz.sshj.common.StreamCopier;
 import net.schmizz.sshj.connection.Connection;
+import net.schmizz.sshj.connection.ConnectionException;
 import net.schmizz.sshj.connection.channel.SocketStreamCopyMonitor;
+import net.schmizz.sshj.transport.TransportException;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import javax.net.ServerSocketFactory;
 import java.io.IOException;
 import java.net.ServerSocket;
 import java.net.Socket;
-import java.net.SocketAddress;
 import java.util.concurrent.TimeUnit;
 
 public class LocalPortForwarder {
 
-    private class DirectTCPIPChannel
-            extends AbstractDirectChannel {
+    public static class Parameters {
 
-        private final Socket sock;
+        private final String localHost;
+        private final int localPort;
+        private final String remoteHost;
+        private final int remotePort;
 
-        private DirectTCPIPChannel(Connection conn, Socket sock) {
-            super(conn, "direct-tcpip");
-            this.sock = sock;
+        public Parameters(String localHost, int localPort, String remoteHost, int remotePort) {
+            this.localHost = localHost;
+            this.localPort = localPort;
+            this.remoteHost = remoteHost;
+            this.remotePort = remotePort;
         }
 
-        private void start()
+        public String getRemoteHost() {
+            return remoteHost;
+        }
+
+        public int getRemotePort() {
+            return remotePort;
+        }
+
+        public String getLocalHost() {
+            return localHost;
+        }
+
+        public int getLocalPort() {
+            return localPort;
+        }
+
+    }
+
+    public static class DirectTCPIPChannel
+            extends AbstractDirectChannel {
+
+        protected final Socket socket;
+        protected final Parameters parameters;
+
+        public DirectTCPIPChannel(Connection conn, Socket socket, Parameters parameters) {
+            super(conn, "direct-tcpip");
+            this.socket = socket;
+            this.parameters = parameters;
+        }
+
+        protected void start()
                 throws IOException {
-            sock.setSendBufferSize(getLocalMaxPacketSize());
-            sock.setReceiveBufferSize(getRemoteMaxPacketSize());
-            final Event<IOException> soc2chan = new StreamCopier(sock.getInputStream(), getOutputStream())
+            socket.setSendBufferSize(getLocalMaxPacketSize());
+            socket.setReceiveBufferSize(getRemoteMaxPacketSize());
+            final Event<IOException> soc2chan = new StreamCopier(socket.getInputStream(), getOutputStream())
                     .bufSize(getRemoteMaxPacketSize())
                     .spawnDaemon("soc2chan");
-            final Event<IOException> chan2soc = new StreamCopier(getInputStream(), sock.getOutputStream())
+            final Event<IOException> chan2soc = new StreamCopier(getInputStream(), socket.getOutputStream())
                     .bufSize(getLocalMaxPacketSize())
                     .spawnDaemon("chan2soc");
-            SocketStreamCopyMonitor.monitor(5, TimeUnit.SECONDS, soc2chan, chan2soc, this, sock);
+            SocketStreamCopyMonitor.monitor(5, TimeUnit.SECONDS, soc2chan, chan2soc, this, socket);
         }
 
         @Override
         protected SSHPacket buildOpenReq() {
             return super.buildOpenReq()
-                        .putString(host)
-                        .putUInt32(port)
-                        .putString(ss.getInetAddress().getHostAddress())
-                        .putUInt32(ss.getLocalPort());
+                    .putString(parameters.getRemoteHost())
+                    .putUInt32(parameters.getRemotePort())
+                    .putString(parameters.getLocalHost())
+                    .putUInt32(parameters.getLocalPort());
         }
 
     }
 
-    private final Logger log = LoggerFactory.getLogger(getClass());
+    private final Logger log = LoggerFactory.getLogger(LocalPortForwarder.class);
 
     private final Connection conn;
-    private final ServerSocket ss;
-    private final String host;
-    private final int port;
+    private final Parameters parameters;
+    private final ServerSocket serverSocket;
 
-    /**
-     * Create a local port forwarder with specified binding ({@code listeningAddr}. It does not, however, start
-     * listening unless {@link #listen() explicitly told to}. The {@link javax.net.ServerSocketFactory#getDefault()
-     * default} server socket factory is used.
-     *
-     * @param conn          {@link Connection} implementation
-     * @param listeningAddr {@link SocketAddress} this forwarder will listen on, if {@code null} then an ephemeral port
-     *                      and valid local address will be picked to bind the server socket
-     * @param host          what host the SSH server will further forward to
-     * @param port          port on {@code toHost}
-     *
-     * @throws IOException if there is an error binding on specified {@code listeningAddr}
-     */
-    public LocalPortForwarder(Connection conn, SocketAddress listeningAddr, String host, int port)
-            throws IOException {
-        this(ServerSocketFactory.getDefault(), conn, listeningAddr, host, port);
-    }
-
-    /**
-     * Create a local port forwarder with specified binding ({@code listeningAddr}. It does not, however, start
-     * listening unless {@link #listen() explicitly told to}.
-     *
-     * @param ssf           factory to use for creating the server socket
-     * @param conn          {@link Connection} implementation
-     * @param listeningAddr {@link SocketAddress} this forwarder will listen on, if {@code null} then an ephemeral port
-     *                      and valid local address will be picked to bind the server socket
-     * @param host          what host the SSH server will further forward to
-     * @param port          port on {@code toHost}
-     *
-     * @throws IOException if there is an error binding on specified {@code listeningAddr}
-     */
-    public LocalPortForwarder(ServerSocketFactory ssf, Connection conn, SocketAddress listeningAddr, String host, int port)
-            throws IOException {
+    public LocalPortForwarder(Connection conn, Parameters parameters, ServerSocket serverSocket) {
         this.conn = conn;
-        this.host = host;
-        this.port = port;
-        this.ss = ssf.createServerSocket();
-        ss.setReceiveBufferSize(conn.getMaxPacketSize());
-        ss.bind(listeningAddr);
+        this.parameters = parameters;
+        this.serverSocket = serverSocket;
     }
 
-    /** @return the address to which this forwarder is bound for listening */
-    public SocketAddress getListeningAddress() {
-        return ss.getLocalSocketAddress();
+    protected DirectTCPIPChannel openChannel(Socket socket)
+            throws TransportException, ConnectionException {
+        final DirectTCPIPChannel chan = new DirectTCPIPChannel(conn, socket, parameters);
+        chan.open();
+        return chan;
     }
 
     /**
@@ -126,14 +126,11 @@ public class LocalPortForwarder {
      */
     public void listen()
             throws IOException {
-        log.info("Listening on {}", ss.getLocalSocketAddress());
-        Socket sock;
+        log.info("Listening on {}", serverSocket.getLocalSocketAddress());
         while (!Thread.currentThread().isInterrupted()) {
-            sock = ss.accept();
-            log.info("Got connection from {}", sock.getRemoteSocketAddress());
-            DirectTCPIPChannel chan = new DirectTCPIPChannel(conn, sock);
-            chan.open();
-            chan.start();
+            final Socket socket = serverSocket.accept();
+            log.info("Got connection from {}", socket.getRemoteSocketAddress());
+            openChannel(socket).start();
         }
         log.info("Interrupted!");
     }