java/net/SocketTest.java

/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

package org.apache.harmony.tests.java.net;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ConnectException;
import java.net.Inet4Address;
import java.net.Inet6Address;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.Proxy;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketAddress;
import java.net.SocketException;
import java.net.SocketImpl;
import java.net.SocketImplFactory;
import java.net.SocketTimeoutException;
import java.net.UnknownHostException;
import java.security.Permission;
import java.util.Arrays;
import java.util.Locale;

import tests.support.Support_Configuration;

public class SocketTest extends junit.framework.TestCase {
    private class ClientThread implements Runnable {

        public void run() {
            try {
                Socket socket = new Socket();
                InetSocketAddress addr = new InetSocketAddress(host, port);
                socket.connect(addr);

                socket.close();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
    }

    private class ServerThread implements Runnable {
        private static final int FIRST_TIME = 1;

        private static final int SECOND_TIME = 2;

        private int backlog = 10;

        public boolean ready = false;

        private int serverSocketConstructor = 0;

        public void run() {
            try {

                ServerSocket socket;
                switch (serverSocketConstructor) {
                    case FIRST_TIME:
                        socket = new ServerSocket(port, backlog,
                                new InetSocketAddress(host, port).getAddress());
                        port = socket.getLocalPort();
                        break;
                    case SECOND_TIME:
                        socket = new ServerSocket(port, backlog);
                        host = socket.getInetAddress().getHostName();
                        port = socket.getLocalPort();
                        break;
                    default:
                        socket = new ServerSocket();
                        break;
                }

                synchronized (this) {
                    ready = true;
                    this.notifyAll();
                }

                socket.setSoTimeout(5000);
                Socket client = socket.accept();
                client.close();
                socket.close();
            } catch (IOException e) {
                e.printStackTrace();
            } catch (Throwable e) {
                e.printStackTrace();
            }
        }

        public synchronized void waitCreated() throws Exception {
            while (!ready) {
                this.wait();
            }
        }
    }

    boolean interrupted;

    String host = "localhost";
    int port;

    Thread t;

    private void connectTestImpl(int ssConsType) throws Exception {
        ServerThread server = new ServerThread();
        server.serverSocketConstructor = ssConsType;
        Thread serverThread = new Thread(server);
        serverThread.start();
        server.waitCreated();

        ClientThread client = new ClientThread();
        Thread clientThread = new Thread(client);
        clientThread.start();
        try {
            serverThread.join();
            clientThread.join();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    protected void tearDown() {
        try {
            if (t != null) {
                t.interrupt();
            }
        } catch (Exception e) {
        }
        this.t = null;
        this.interrupted = false;
    }

    /**
     * java.net.Socket#bind(java.net.SocketAddress)
     */
    public void test_bindLjava_net_SocketAddress() throws IOException {

        @SuppressWarnings("serial")
        class UnsupportedSocketAddress extends SocketAddress {
            public UnsupportedSocketAddress() {
            }
        }

        // Address we cannot bind to
        Socket theSocket = new Socket();
        InetSocketAddress bogusAddress = new InetSocketAddress(InetAddress
                .getByAddress(Support_Configuration.nonLocalAddressBytes), 42);
        try {
            theSocket.bind(bogusAddress);
            fail("No exception when binding to bad address");
        } catch (IOException ex) {
            // Expected
        }
        theSocket.close();

        // Now create a socket that is not bound and then bind it
        theSocket = new Socket();
        theSocket.bind(new InetSocketAddress(InetAddress.getLocalHost(), 0));
        int portNumber = theSocket.getLocalPort();

        // Validate that the localSocketAddress reflects the address we
        // bound to
        assertEquals("Local address not correct after bind",
                new InetSocketAddress(InetAddress.getLocalHost(), portNumber),
                theSocket.getLocalSocketAddress());

        // Make sure we can now connect and that connections appear to come
        // from the address we bound to.
        InetSocketAddress theAddress = new InetSocketAddress(InetAddress
                .getLocalHost(), 0);
        ServerSocket server = new ServerSocket();
        server.bind(theAddress);
        int sport = server.getLocalPort();
        InetSocketAddress boundAddress = new InetSocketAddress(InetAddress
                .getLocalHost(), sport);

        theSocket.connect(boundAddress);
        Socket worker = server.accept();
        assertEquals(
                "Returned Remote address from server connected to does not match expected local address",
                new InetSocketAddress(InetAddress.getLocalHost(), portNumber),
                worker.getRemoteSocketAddress());
        theSocket.close();
        worker.close();
        server.close();

        // Validate if we pass in null that it picks an address for us and
        // all is ok
        theSocket = new Socket();
        theSocket.bind(null);
        assertNotNull("Bind with null did not work", theSocket
                .getLocalSocketAddress());
        theSocket.close();

        // now check the error conditions

        // Address that we have already bound to
        theSocket = new Socket();
        theAddress = new InetSocketAddress(InetAddress.getLocalHost(), 0);
        theSocket.bind(theAddress);

        Socket theSocket2 = new Socket();
        try {
            theSocket2.bind(theSocket.getLocalSocketAddress());
            fail("No exception binding to address that is not available");
        } catch (IOException ex) {
            // Expected
        }
        theSocket.close();
        theSocket2.close();

        // Unsupported SocketAddress subclass
        theSocket = new Socket();
        try {
            theSocket.bind(new UnsupportedSocketAddress());
            fail("No exception when binding using unsupported SocketAddress subclass");
        } catch (IllegalArgumentException ex) {
            // Expected
        }
        theSocket.close();
    }

    /**
     * java.net.Socket#bind(java.net.SocketAddress)
     */
    public void test_bindLjava_net_SocketAddress_Proxy() throws IOException {
        // The Proxy will not impact on the bind operation. It can be assigned
        // with any address.
        Proxy proxy = new Proxy(Proxy.Type.SOCKS, new InetSocketAddress(
                "127.0.0.1", 0));
        Socket socket = new Socket(proxy);

        InetAddress address = InetAddress.getByName("localhost");
        socket.bind(new InetSocketAddress(address, 0));

        assertEquals(address, socket.getLocalAddress());
        assertTrue(0 != socket.getLocalPort());

        socket.close();
    }

    public void test_close() throws IOException {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server.getLocalPort());

        client.setSoLinger(false, 100);

        client.close();
        try {
            client.getOutputStream();
            fail("Failed to close socket");
        } catch (IOException expected) {
        }

        server.close();
    }

    public void test_connect_unknownhost() throws Exception {
        Socket socket = new Socket();
        try {
            socket.connect(new InetSocketAddress("1.2.3.4hello", 12345));
            fail();
        } catch (UnknownHostException expected) {
        }
    }

    public void test_connect_unresolved() throws IOException {
        Socket socket = new Socket();
        InetSocketAddress unresolved = InetSocketAddress.createUnresolved("www.apache.org", 80);
        try {
            socket.connect(unresolved);
            fail();
        } catch (UnknownHostException expected) {
        }
        try {
            socket.connect(unresolved, 123);
            fail();
        } catch (UnknownHostException expected) {
        }
    }

    public void test_connectLjava_net_SocketAddress() throws Exception {

        @SuppressWarnings("serial")
        class UnsupportedSocketAddress extends SocketAddress {
            public UnsupportedSocketAddress() {
            }
        }

        Socket theSocket = new Socket();
        try {
            theSocket.connect(null);
            fail("No exception for null arg");
        } catch (IllegalArgumentException e) {
            // Expected
        }

        try {
            theSocket.connect(new UnsupportedSocketAddress());
            fail("No exception for invalid socket address");
        } catch (IllegalArgumentException e) {
            // Expected
        }

        try {
            theSocket.connect(new InetSocketAddress(InetAddress
                    .getByAddress(new byte[] { 0, 0, 0, 0 }), 42));
            fail("No exception with non-connectable address");
        } catch (ConnectException e) {
            // Expected
        }

        // now validate that we get a connect exception if we try to connect to
        // an address on which nobody is listening
        theSocket = new Socket();
        try {
            theSocket.connect(new InetSocketAddress(InetAddress.getLocalHost(),
                    0));
            fail("No exception when connecting to address nobody listening on");
        } catch (ConnectException e) {
            // Expected
        }

        // Now validate that we can actually connect when somebody is listening
        ServerSocket server = new ServerSocket(0);
        InetSocketAddress boundAddress = new InetSocketAddress(InetAddress
                .getLocalHost(), server.getLocalPort());
        Socket client = new Socket();
        client.connect(boundAddress);

        // validate that when a socket is connected that it answers
        // correctly to related queries
        assertTrue("Wrong connected status", client.isConnected());
        assertFalse("Wrong closed status", client.isClosed());
        assertTrue("Wrong bound status", client.isBound());
        assertFalse("Wrong input shutdown status", client.isInputShutdown());
        assertFalse("Wrong output shutdown status", client.isOutputShutdown());
        assertTrue("Local port was 0", client.getLocalPort() != 0);

        client.close();
        server.close();

        // Now validate that we get the right exception if we connect when we
        // are already connected
        server = new ServerSocket(0);
        boundAddress = new InetSocketAddress(InetAddress.getLocalHost(), server
                .getLocalPort());
        client = new Socket();
        client.connect(boundAddress);

        try {
            client.connect(boundAddress);
            fail("No exception when we try to connect on a connected socket: ");
        } catch (SocketException e) {
            // Expected
        }
        client.close();
        server.close();
    }

    /**
     * Regression for Harmony-2503
     */
    public void test_connectLjava_net_SocketAddress_AnyAddress()
            throws Exception {
        connectTestImpl(ServerThread.FIRST_TIME);
        connectTestImpl(ServerThread.SECOND_TIME);
    }

    /**
     * java.net.Socket#connect(java.net.SocketAddress, int)
     */
    public void test_connectLjava_net_SocketAddressI() throws Exception {

        @SuppressWarnings("serial")
        class UnsupportedSocketAddress extends SocketAddress {
            public UnsupportedSocketAddress() {
            }
        }

        // Start by validating the error checks
        Socket theSocket = new Socket();
        try {
            theSocket.connect(new InetSocketAddress(0), -100);
            fail("No exception for negative timeout");
        } catch (IllegalArgumentException e) {
            // Expected
        }

        try {
            theSocket.connect(null, 0);
            fail("No exception for null address");
        } catch (IllegalArgumentException e) {
            // Expected
        }

        try {
            theSocket.connect(new UnsupportedSocketAddress(), 1000);
            fail("No exception for invalid socket address type");
        } catch (IllegalArgumentException e) {
            // Expected
        }

        SocketAddress nonConnectableAddress = new InetSocketAddress(InetAddress
                .getByAddress(new byte[] { 0, 0, 0, 0 }), 0);
        try {
            theSocket.connect(nonConnectableAddress, 1000);
            fail("No exception when non Connectable Address passed in: ");
        } catch (SocketException e) {
            // Expected
        }

        // Now validate that we get a connect exception if we try to connect to
        // an address on which nobody is listening
        theSocket = new Socket();
        try {
            theSocket.connect(new InetSocketAddress(InetAddress.getLocalHost(),
                    0), 0);
            fail("No exception when connecting to address nobody listening on");
        } catch (ConnectException e) {
            // Expected
        }
        theSocket.close();

        // Now validate that we can actually connect when somebody is listening
        ServerSocket server = new ServerSocket(0);
        InetSocketAddress boundAddress = new InetSocketAddress(InetAddress
                .getLocalHost(), server.getLocalPort());
        Socket client = new Socket();
        client.connect(boundAddress, 0);

        // Validate that when a socket is connected that it answers
        // correctly to related queries
        assertTrue("Wrong connected status", client.isConnected());
        assertFalse("Wrong closed status", client.isClosed());
        assertTrue("Wrong bound status", client.isBound());
        assertFalse("Wrong input shutdown status", client.isInputShutdown());
        assertFalse("Wrong output shutdown status", client.isOutputShutdown());
        assertTrue("Local port was 0", client.getLocalPort() != 0);

        client.close();
        server.close();

        // Now validate that we get a connect exception if we try to connect to
        // an address on which nobody is listening
        theSocket = new Socket();
        SocketAddress nonListeningAddress = new InetSocketAddress(InetAddress
                .getLocalHost(), 42);
        try {
            theSocket.connect(nonListeningAddress, 1000);
            fail("No exception when connecting to address nobody listening on");
        } catch (ConnectException e) {
            // Expected
        } catch (SocketTimeoutException e) {
            // The other possibility is that the system timed us out.
        }
        theSocket.close();

        // Now validate that we get the right exception if we connect when we
        // are already connected
        server = new ServerSocket(0);
        boundAddress = new InetSocketAddress(InetAddress.getLocalHost(), server
                .getLocalPort());
        client = new Socket();
        client.connect(boundAddress, 10000);

        try {
            client.connect(boundAddress, 10000);
            fail("No exception when we try to connect on a connected socket: ");
        } catch (SocketException e) {
            // Expected
        }
        client.close();
        server.close();
    }

    /**
     * java.net.Socket#Socket()
     */
    public void test_Constructor() {
        // create the socket and then validate some basic state
        Socket s = new Socket();
        assertFalse("new socket should not be connected", s.isConnected());
        assertFalse("new socket should not be bound", s.isBound());
        assertFalse("new socket should not be closed", s.isClosed());
        assertFalse("new socket should not be in InputShutdown", s
                .isInputShutdown());
        assertFalse("new socket should not be in OutputShutdown", s
                .isOutputShutdown());
    }

    /**
     * java.net.Socket#Socket(java.lang.String, int)
     */
    public void test_ConstructorLjava_lang_StringI() throws IOException {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server
                .getLocalPort());

        assertEquals("Failed to create socket", server.getLocalPort(), client
                .getPort());

        // Regression for HARMONY-946
        ServerSocket ss = new ServerSocket(0);
        Socket s = new Socket("0.0.0.0", ss.getLocalPort());
        ss.close();
        s.close();
    }

    /**
     * java.net.Socket#Socket(java.lang.String, int,
     *java.net.InetAddress, int)
     */
    public void test_ConstructorLjava_lang_StringILjava_net_InetAddressI()
            throws IOException {

        ServerSocket server = new ServerSocket(0);
        int serverPort = server.getLocalPort();
        Socket client = new Socket(InetAddress.getLocalHost().getHostName(),
                serverPort, InetAddress.getLocalHost(), 0);
        assertTrue("Failed to create socket", client.getPort() == serverPort);
        client.close();

        Socket theSocket;
        try {
            theSocket = new Socket("127.0.0.1", serverPort, InetAddress
                    .getLocalHost(), 0);
        } catch (IOException e) {
            // check here if InetAddress.getLocalHost() is returning the
            // loopback address, if so that is likely the cause of the failure
            assertFalse(
                    "Misconfiguration - local host is the loopback address",
                    InetAddress.getLocalHost().isLoopbackAddress());
            throw e;
        }

        assertTrue(theSocket.isConnected());

        try {
            new Socket("127.0.0.1", serverPort, theSocket.getLocalAddress(),
                    theSocket.getLocalPort());
            fail("Was able to create two sockets on same port");
        } catch (IOException e) {
            // Expected
        }

        theSocket.close();
        server.close();
    }

    @SuppressWarnings("deprecation")
    public void test_ConstructorLjava_lang_StringIZ() throws IOException {
        ServerSocket server = new ServerSocket(0);
        int serverPort = server.getLocalPort();
        Socket client = new Socket(InetAddress.getLocalHost().getHostAddress(),
                serverPort, true);

        assertEquals("Failed to create socket", serverPort, client.getPort());
        client.close();

        client = new Socket(InetAddress.getLocalHost().getHostName(),
                serverPort, false);
        client.close();
        server.close();
    }

    /**
     * java.net.Socket#Socket(java.net.InetAddress, int)
     */
    public void test_ConstructorLjava_net_InetAddressI() throws IOException {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server
                .getLocalPort());

        assertEquals("Failed to create socket", server.getLocalPort(), client
                .getPort());

        client.close();
        server.close();
    }

    /**
     * java.net.Socket#Socket(java.net.InetAddress, int,
     *java.net.InetAddress, int)
     */
    public void test_ConstructorLjava_net_InetAddressILjava_net_InetAddressI()
            throws IOException {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server
                .getLocalPort(), InetAddress.getLocalHost(), 0);
        assertNotSame("Failed to create socket", 0, client.getLocalPort());
    }

    /**
     * java.net.Socket#Socket(java.net.InetAddress, int, boolean)
     */
    @SuppressWarnings("deprecation")
    public void test_ConstructorLjava_net_InetAddressIZ() throws IOException {
        ServerSocket server = new ServerSocket(0);
        int serverPort = server.getLocalPort();

        Socket client = new Socket(InetAddress.getLocalHost(), serverPort, true);
        assertEquals("Failed to create socket", serverPort, client.getPort());

        client = new Socket(InetAddress.getLocalHost(), serverPort, false);
        client.close();
    }

    /**
     * java.net.Socket#Socket(Proxy)
     */
    public void test_ConstructorLjava_net_Proxy_Exception() {

        SocketAddress addr1 = InetSocketAddress.createUnresolved("127.0.0.1", 80);

        Proxy proxy1 = new Proxy(Proxy.Type.HTTP, addr1);
        // IllegalArgumentException test
        try {
            new Socket(proxy1);
            fail("should throw IllegalArgumentException");
        } catch (IllegalArgumentException e) {
            // expected
        }

        Proxy proxy2 = new Proxy(Proxy.Type.SOCKS, addr1);
        // should not throw any exception
        new Socket(proxy2);
        new Socket(Proxy.NO_PROXY);
    }

    /**
     * java.net.Socket#getChannel()
     */
    public void test_getChannel() {
        assertNull(new Socket().getChannel());
    }

    /**
     * java.net.Socket#getInetAddress()
     */
    public void test_getInetAddress() throws IOException {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server
                .getLocalPort());

        assertTrue("Returned incorrect InetAdrees", client.getInetAddress()
                .equals(InetAddress.getLocalHost()));

        client.close();
        server.close();
    }

    /**
     * java.net.Socket#getInputStream()
     */
    public void test_getInputStream() throws IOException {
        // Simple fetch test
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server
                .getLocalPort());
        InputStream is = client.getInputStream();
        assertNotNull("Failed to get stream", is);
        is.close();
        client.close();
        server.close();
    }

    private boolean isUnix() {
        String osName = System.getProperty("os.name");

        // only comparing ASCII, so assume english locale
        osName = (osName == null ? null : osName.toLowerCase(Locale.ENGLISH));

        if (osName != null && osName.startsWith("windows")) { //$NON-NLS-1$
            return false;
        }
        return true;
    }

    public void test_getKeepAlive() throws Exception {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server.getLocalPort(), null, 0);

        client.setKeepAlive(true);
        assertTrue("getKeepAlive false when it should be true", client.getKeepAlive());

        client.setKeepAlive(false);
        assertFalse("getKeepAlive true when it should be False", client.getKeepAlive());
    }

    public void test_getLocalAddress() throws IOException {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server.getLocalPort());

        assertTrue("Returned incorrect InetAddress", client.getLocalAddress()
                .equals(InetAddress.getLocalHost()));

        client = new Socket();
        client.bind(new InetSocketAddress(InetAddress.getByName("0.0.0.0"), 0));
        assertTrue(client.getLocalAddress().isAnyLocalAddress());

        client.close();
        server.close();
    }

    /**
     * java.net.Socket#getLocalPort()
     */
    public void test_getLocalPort() throws IOException {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server
                .getLocalPort());

        assertNotSame("Returned incorrect port", 0, client.getLocalPort());

        client.close();
        server.close();
    }

    public void test_getLocalSocketAddress() throws IOException {
        // set up server connect and then validate that we get the right
        // response for the local address
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server
                .getLocalPort());
        int clientPort = client.getLocalPort();

        assertEquals("Returned incorrect InetSocketAddress(1):",
                new InetSocketAddress(InetAddress.getLocalHost(), clientPort),
                client.getLocalSocketAddress());
        client.close();
        server.close();

        // now create a socket that is not bound and validate we get the
        // right answer
        client = new Socket();
        assertNull(
                "Returned incorrect InetSocketAddress -unbound socket- Expected null",
                client.getLocalSocketAddress());

        // now bind the socket and make sure we get the right answer
        client.bind(new InetSocketAddress(InetAddress.getLocalHost(), 0));
        clientPort = client.getLocalPort();
        assertEquals("Returned incorrect InetSocketAddress(2):",
                new InetSocketAddress(InetAddress.getLocalHost(), clientPort),
                client.getLocalSocketAddress());
        client.close();

        // now validate the behaviour when the any address is returned
        client = new Socket();
        client.bind(new InetSocketAddress(InetAddress.getByName("0.0.0.0"), 0));
        assertTrue(((InetSocketAddress) client.getLocalSocketAddress()).getAddress().isAnyLocalAddress());
        client.close();

        // now validate the same for getLocalAddress
        client = new Socket();
        client.bind(new InetSocketAddress(InetAddress.getByName("0.0.0.0"), 0));
        assertTrue(client.getLocalAddress().isAnyLocalAddress());
        client.close();
    }

    public void test_getOOBInline() throws Exception {
        Socket theSocket = new Socket();

        theSocket.setOOBInline(true);
        assertTrue("expected OOBIline to be true", theSocket.getOOBInline());

        theSocket.setOOBInline(false);
        assertFalse("expected OOBIline to be false", theSocket.getOOBInline());

        theSocket.setOOBInline(false);
        assertFalse("expected OOBIline to be false", theSocket.getOOBInline());
    }

    /**
     * java.net.Socket#getOutputStream()
     */
    @SuppressWarnings("deprecation")
    public void test_getOutputStream() throws IOException {
        // Simple fetch test
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server
                .getLocalPort());
        OutputStream os = client.getOutputStream();
        assertNotNull("Failed to get stream", os);
        os.close();
        client.close();
        server.close();

        // Simple read/write test over the IO streams
        final ServerSocket sinkServer = new ServerSocket(0);
        Runnable runnable = new Runnable() {
            public void run() {
                try {
                    Socket worker = sinkServer.accept();
                    sinkServer.close();
                    InputStream in = worker.getInputStream();
                    in.read();
                    in.close();
                    worker.close();
                } catch (IOException e) {
                    fail();
                }
            }
        };
        Thread thread = new Thread(runnable, "Socket.getOutputStream");
        thread.start();

        Socket pingClient = new Socket(InetAddress.getLocalHost(), sinkServer
                .getLocalPort());

        // Busy wait until the client is connected.
        int c = 0;
        while (!pingClient.isConnected()) {
            try {
                Thread.sleep(200);
            } catch (InterruptedException e) {
            }
            if (++c > 4) {
                fail("thread is not alive");
            }
        }

        // Write some data to the server
        OutputStream out = pingClient.getOutputStream();
        out.write(new byte[256]);

        // Wait for the server to finish
        Thread.yield();
        c = 0;
        while (thread.isAlive()) {
            try {
                Thread.sleep(200);
            } catch (InterruptedException e) {
            }
            if (++c > 4) {
                fail("read call did not exit");
            }
        }

        // Subsequent writes should throw an exception
        try {
            // The output buffer may remain valid until the close completes
            for (int i = 0; i < 400; i++) {
                out.write(new byte[256]);
            }
            fail("write to closed socket did not cause exception");
        } catch (IOException e) {
            // Expected
        }

        out.close();
        pingClient.close();
        sinkServer.close();

        // Regression test for HARMONY-873
        ServerSocket ss2 = new ServerSocket(0);
        Socket s = new Socket("127.0.0.1", ss2.getLocalPort());
        ss2.accept();
        s.shutdownOutput();
        try {
            s.getOutputStream();
            fail("should throw SocketException");
        } catch (SocketException e) {
            // expected
        }
    }

    public void test_getPort() throws IOException {
        ServerSocket server = new ServerSocket(0);
        int serverPort = server.getLocalPort();
        Socket client = new Socket(InetAddress.getLocalHost(), serverPort);

        assertEquals("Returned incorrect port", serverPort, client.getPort());

        client.close();
        server.close();
    }

    public void test_getReceiveBufferSize() throws Exception {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server.getLocalPort());
        client.setReceiveBufferSize(130);

        assertTrue("Incorrect buffer size", client.getReceiveBufferSize() >= 130);

        client.close();
        server.close();
    }

    /**
     * java.net.Socket#getRemoteSocketAddress()
     */
    public void test_getRemoteSocketAddress() throws IOException {
        // set up server connect and then validate that we get the right
        // response for the remote address
        ServerSocket server = new ServerSocket(0);
        int serverPort = server.getLocalPort();
        Socket client = new Socket(InetAddress.getLocalHost(), serverPort);

        assertEquals("Returned incorrect InetSocketAddress(1):",
                new InetSocketAddress(InetAddress.getLocalHost(), serverPort),
                client.getRemoteSocketAddress());
        client.close();

        // now create one that is not connected and validate that we get the
        // right answer
        Socket theSocket = new Socket();
        theSocket.bind(new InetSocketAddress(InetAddress.getLocalHost(), 0));
        assertNull("Returned incorrect InetSocketAddress -unconnected socket:",
                theSocket.getRemoteSocketAddress());

        // now connect and validate we get the right answer
        theSocket.connect(new InetSocketAddress(InetAddress.getLocalHost(),
                serverPort));
        assertEquals("Returned incorrect InetSocketAddress(2):",
                new InetSocketAddress(InetAddress.getLocalHost(), serverPort),
                theSocket.getRemoteSocketAddress());
        theSocket.close();

        server.close();
    }

    public void test_getReuseAddress() throws Exception {
        Socket theSocket = new Socket();
        theSocket.setReuseAddress(true);
        assertTrue("getReuseAddress false when it should be true", theSocket.getReuseAddress());
        theSocket.setReuseAddress(false);
        assertFalse("getReuseAddress true when it should be False", theSocket.getReuseAddress());
    }

    public void test_getSendBufferSize() throws Exception {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server.getLocalPort());
        client.setSendBufferSize(134);
        assertTrue("Incorrect buffer size", client.getSendBufferSize() >= 134);
        client.close();
        server.close();
    }

    public void test_getSoLinger() throws Exception {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server.getLocalPort());
        client.setSoLinger(true, 200);
        assertEquals("Returned incorrect linger", 200, client.getSoLinger());
        client.setSoLinger(false, 0);
        client.close();
        server.close();
    }

    public void test_getSoTimeout() throws Exception {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server.getLocalPort());
        final int timeoutSet = 100;
        client.setSoTimeout(timeoutSet);
        int actualTimeout = client.getSoTimeout();
        // The kernel can round the requested value based on the HZ setting. We allow up to 10ms.
        assertTrue("Returned incorrect sotimeout", Math.abs(timeoutSet - actualTimeout) <= 10);
        client.close();
        server.close();
    }

    public void test_getTcpNoDelay() throws Exception {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server.getLocalPort());

        boolean bool = !client.getTcpNoDelay();
        client.setTcpNoDelay(bool);
        assertTrue("Failed to get no delay setting: " + client.getTcpNoDelay(), client.getTcpNoDelay() == bool);

        client.close();
        server.close();
    }

    public void test_getTrafficClass() throws Exception {
        /*
         * We cannot actually check that the values are set as if a platform
         * does not support the option then it may come back unset even
         * though we set it so just get the value to make sure we can get it
         */
        int trafficClass = new Socket().getTrafficClass();
        assertTrue(0 <= trafficClass);
        assertTrue(trafficClass <= 255);
    }

    /**
     * java.net.Socket#isBound()
     */
    public void test_isBound() throws IOException {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server
                .getLocalPort());
        Socket worker = server.accept();

        assertTrue("Socket indicated  not bound when it should be (1)", client
                .isBound());
        worker.close();
        client.close();
        server.close();

        client = new Socket();
        assertFalse("Socket indicated bound when it was not (2)", client
                .isBound());

        server = new ServerSocket();
        server.bind(new InetSocketAddress(InetAddress.getLocalHost(), 0));
        InetSocketAddress boundAddress = new InetSocketAddress(server
                .getInetAddress(), server.getLocalPort());
        client.connect(boundAddress);
        worker = server.accept();
        assertTrue("Socket indicated not bound when it should be (2)", client
                .isBound());
        worker.close();
        client.close();
        server.close();

        // now test when we bind explicitly
        InetSocketAddress theLocalAddress = new InetSocketAddress(InetAddress
                .getLocalHost(), 0);
        client = new Socket();
        assertFalse("Socket indicated bound when it was not (3)", client
                .isBound());
        client.bind(theLocalAddress);
        assertTrue("Socket indicated not bound when it should be (3a)", client
                .isBound());
        client.close();
        assertTrue("Socket indicated not bound when it should be (3b)", client
                .isBound());
    }

    /**
     * java.net.Socket#isClosed()
     */
    public void test_isClosed() throws IOException {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server
                .getLocalPort());
        Socket worker = server.accept();

        // validate isClosed returns expected values
        assertFalse("Socket should indicate it is not closed(1):", client
                .isClosed());
        client.close();
        assertTrue("Socket should indicate it is closed(1):", client.isClosed());

        // validate that isClosed works ok for sockets returned from
        // ServerSocket.accept()
        assertFalse("Accepted Socket should indicate it is not closed:", worker
                .isClosed());
        worker.close();
        assertTrue("Accepted Socket should indicate it is closed:", worker
                .isClosed());

        // and finally for the server socket
        assertFalse("Server Socket should indicate it is not closed:", server
                .isClosed());
        server.close();
        assertTrue("Server Socket should indicate it is closed:", server
                .isClosed());
    }

    /**
     * java.net.Socket#isConnected()
     */
    public void test_isConnected() throws IOException {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server
                .getLocalPort());
        Socket worker = server.accept();

        assertTrue("Socket indicated  not connected when it should be", client
                .isConnected());
        client.close();
        worker.close();
        server.close();

        // now do it with the new constructors and revalidate
        InetSocketAddress theAddress = new InetSocketAddress(InetAddress
                .getLocalHost(), 0);
        client = new Socket();
        assertFalse("Socket indicated connected when it was not", client
                .isConnected());

        server = new ServerSocket();
        server.bind(theAddress);
        InetSocketAddress boundAddress = new InetSocketAddress(server
                .getInetAddress(), server.getLocalPort());
        client.connect(boundAddress);
        worker = server.accept();
        assertTrue("Socket indicated  not connected when it should be", client
                .isConnected());
        client.close();
        worker.close();
        server.close();
    }

    /**
     * java.net.Socket#isInputShutdown()
     */
    public void test_isInputShutdown() throws IOException {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server
                .getLocalPort());

        Socket worker = server.accept();
        InputStream theInput = client.getInputStream();
        OutputStream theOutput = worker.getOutputStream();

        // make sure we get the right answer with newly connected socket
        assertFalse("Socket indicated input shutdown when it should not have",
                client.isInputShutdown());

        // shutdown the output
        client.shutdownInput();

        // make sure we get the right answer once it is shut down
        assertTrue(
                "Socket indicated input was NOT shutdown when it should have been",
                client.isInputShutdown());

        client.close();
        worker.close();
        server.close();

        // make sure we get the right answer for closed sockets
        assertFalse(
                "Socket indicated input was shutdown when socket was closed",
                worker.isInputShutdown());

        theInput.close();
        theOutput.close();
    }

    /**
     * java.net.Socket#isOutputShutdown()
     */
    public void test_isOutputShutdown() throws IOException {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server
                .getLocalPort());

        Socket worker = server.accept();
        InputStream theInput = client.getInputStream();
        OutputStream theOutput = worker.getOutputStream();

        // make sure we get the right answer with newly connected socket
        assertFalse("Socket indicated output shutdown when it should not have",
                worker.isOutputShutdown());

        // shutdown the output
        worker.shutdownOutput();

        // make sure we get the right answer once it is shut down
        assertTrue(
                "Socket indicated output was NOT shutdown when it should have been",
                worker.isOutputShutdown());

        client.close();
        worker.close();
        server.close();

        // make sure we get the right answer for closed sockets
        assertFalse(
                "Socket indicated output was output shutdown when the socket was closed",
                client.isOutputShutdown());

        theInput.close();
        theOutput.close();
    }

    /**
     * java.net.Socket#sendUrgentData(int)
     */
    public void test_sendUrgentDataI() throws Exception {
        /*
         * Some platforms may not support urgent data in this case we will not
         * run these tests. For now run on all platforms until we find those
         * that do not support urgent data
         */
        String platform = System.getProperty("os.name");
        if (platform.equals("Dummy")) {
            return;
        }

        /*
         * Test 1: Validate that when OOBInline is false that any urgent data is
         * silently ignored
         */
        InetAddress localHost = InetAddress.getLocalHost();
        ServerSocket server = new ServerSocket(0, 5, localHost);
        SocketAddress serverAddress = new InetSocketAddress(localHost, server
                .getLocalPort());

        Socket client = new Socket();
        client.setOOBInline(false);

        client.connect(serverAddress);
        Socket worker = server.accept();
        worker.setTcpNoDelay(true);
        OutputStream theOutput = worker.getOutputStream();

        // Send the regular data
        byte[] sendBytes = "Test".getBytes();
        theOutput.write(sendBytes);
        theOutput.flush();

        // Send the urgent data byte which should not be received
        worker.sendUrgentData("UrgentData".getBytes()[0]);
        theOutput.write(sendBytes);
        worker.shutdownOutput();
        worker.close();

        // Try to read the bytes back
        int totalBytesRead = 0;
        byte[] myBytes = new byte[100];
        InputStream theInput = client.getInputStream();
        while (true) {
            int bytesRead = theInput.read(myBytes, totalBytesRead,
                    myBytes.length - totalBytesRead);
            if (bytesRead == -1) {
                break;
            }
            totalBytesRead = totalBytesRead + bytesRead;
        }

        client.close();
        server.close();

        byte[] expectBytes = new byte[2 * sendBytes.length];
        System.arraycopy(sendBytes, 0, expectBytes, 0, sendBytes.length);
        System.arraycopy(sendBytes, 0, expectBytes, sendBytes.length,
                sendBytes.length);

        byte[] resultBytes = new byte[totalBytesRead];
        System.arraycopy(myBytes, 0, resultBytes, 0, totalBytesRead);

        assertTrue("Urgent data was received", Arrays.equals(expectBytes,
                resultBytes));

        /*
         * Test 2: Now validate that urgent data is received as expected. Expect
         * that it should be between the two writes.
         */
        server = new ServerSocket(0, 5, localHost);
        serverAddress = new InetSocketAddress(localHost, server.getLocalPort());

        client = new Socket();
        client.setOOBInline(true);

        client.connect(serverAddress);
        worker = server.accept();
        worker.setTcpNoDelay(true);
        theOutput = worker.getOutputStream();

        // Send the regular data
        sendBytes = "Test - Urgent Data".getBytes();
        theOutput.write(sendBytes);

        // Send the urgent data (one byte) which should be received
        client.setOOBInline(true);
        byte urgentByte = "UrgentData".getBytes()[0];
        worker.sendUrgentData(urgentByte);

        // Send more data, the urgent byte must stay in position
        theOutput.write(sendBytes);
        worker.shutdownOutput();
        worker.close();

        // Try to read the bytes back
        totalBytesRead = 0;
        myBytes = new byte[100];
        theInput = client.getInputStream();
        while (true) {
            int bytesRead = theInput.read(myBytes, totalBytesRead,
                    myBytes.length - totalBytesRead);
            if (bytesRead == -1) {
                break;
            }
            totalBytesRead = totalBytesRead + bytesRead;
        }

        client.close();
        server.close();

        expectBytes = new byte[2 * sendBytes.length + 1];
        System.arraycopy(sendBytes, 0, expectBytes, 0, sendBytes.length);
        expectBytes[sendBytes.length] = urgentByte;
        System.arraycopy(sendBytes, 0, expectBytes, sendBytes.length + 1,
                sendBytes.length);

        resultBytes = new byte[totalBytesRead];
        System.arraycopy(myBytes, 0, resultBytes, 0, totalBytesRead);

        assertTrue("Urgent data was not received with one urgent byte", Arrays
                .equals(expectBytes, resultBytes));

        /*
         * Test 3: Now validate that urgent data is received as expected. Expect
         * that it should be between the two writes.
         */
        server = new ServerSocket(0, 5, localHost);
        serverAddress = new InetSocketAddress(localHost, server.getLocalPort());

        client = new Socket();
        client.setOOBInline(true);

        client.connect(serverAddress);
        worker = server.accept();
        worker.setTcpNoDelay(true);
        theOutput = worker.getOutputStream();

        // Send the regular data
        sendBytes = "Test - Urgent Data".getBytes();
        theOutput.write(sendBytes);

        // Send the urgent data (one byte) which should be received
        client.setOOBInline(true);
        byte urgentByte1 = "UrgentData".getBytes()[0];
        byte urgentByte2 = "UrgentData".getBytes()[1];
        worker.sendUrgentData(urgentByte1);
        worker.sendUrgentData(urgentByte2);

        // Send more data, the urgent byte must stay in position
        theOutput.write(sendBytes);
        worker.shutdownOutput();
        worker.close();

        // Try to read the bytes back
        totalBytesRead = 0;
        myBytes = new byte[100];
        theInput = client.getInputStream();
        while (true) {
            int bytesRead = theInput.read(myBytes, totalBytesRead,
                    myBytes.length - totalBytesRead);
            if (bytesRead == -1) {
                break;
            }
            totalBytesRead = totalBytesRead + bytesRead;
        }

        client.close();
        server.close();

        expectBytes = new byte[2 * sendBytes.length + 2];
        System.arraycopy(sendBytes, 0, expectBytes, 0, sendBytes.length);
        expectBytes[sendBytes.length] = urgentByte1;
        expectBytes[sendBytes.length + 1] = urgentByte2;
        System.arraycopy(sendBytes, 0, expectBytes, sendBytes.length + 2,
                sendBytes.length);

        resultBytes = new byte[totalBytesRead];
        System.arraycopy(myBytes, 0, resultBytes, 0, totalBytesRead);

        assertTrue("Urgent data was not received with two urgent bytes", Arrays
                .equals(expectBytes, resultBytes));

        /*
         * Test 4: Now test the case where there is only urgent data.
         */
        server = new ServerSocket(0, 5, localHost);
        serverAddress = new InetSocketAddress(localHost, server.getLocalPort());

        client = new Socket();
        client.setOOBInline(true);

        client.connect(serverAddress);
        worker = server.accept();
        worker.setTcpNoDelay(true);

        // Send the urgent data (one byte) which should be received
        client.setOOBInline(true);
        urgentByte = "UrgentData".getBytes()[0];
        worker.sendUrgentData(urgentByte);
        worker.close();

        // Try to read the bytes back
        theInput = client.getInputStream();
        int byteRead = theInput.read();

        client.close();
        server.close();

        assertEquals("Sole urgent data was not received",
                (int) (urgentByte & 0xff), byteRead);
    }

    /**
     * java.net.Socket#setKeepAlive(boolean)
     */
    public void test_setKeepAliveZ() throws IOException {

        class TestSocket extends Socket {
            public TestSocket(SocketImpl impl) throws SocketException {
                super(impl);
            }
        }

        // There is not really a good test for this as it is there to detect
        // crashed machines. Just make sure we can set it
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server.getLocalPort());

        client.setKeepAlive(true);
        client.setKeepAlive(false);
        client.close();
        server.close();

        // Regression test for HARMONY-1136
        new TestSocket(null).setKeepAlive(true);
    }

    public void test_setOOBInlineZ() throws Exception {
        Socket theSocket = new Socket();
        theSocket.setOOBInline(true);
        assertTrue("expected OOBIline to be true", theSocket.getOOBInline());
    }

    public void test_setPerformancePreference_Int_Int_Int() throws IOException {
        Socket theSocket = new Socket();
        theSocket.setPerformancePreferences(1, 1, 1);
    }

    public void test_setReceiveBufferSizeI() throws Exception {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server.getLocalPort());

        client.setReceiveBufferSize(130);
        assertTrue("Incorrect buffer size", client.getReceiveBufferSize() >= 130);

        client.close();
        server.close();
    }

    public void test_setReuseAddressZ() throws Exception {
        Socket theSocket = new Socket();
        theSocket.setReuseAddress(false);
        // Bind to any available port on the given address
        theSocket.bind(new InetSocketAddress(InetAddress.getLocalHost(), 0));
        InetSocketAddress localAddress1 = new InetSocketAddress(theSocket.getLocalAddress(), theSocket.getLocalPort());

        Socket theSocket2 = new Socket();
        theSocket2.setReuseAddress(false);

        /*
         * Try to invoke a bind while the port is busy (TIME_WAIT). Note
         * that we may not succeed, which will cause the test to pass
         * without testing the reuseaddr behavior.
         */
        theSocket.close();
        theSocket2.bind(localAddress1);

        theSocket2.close();
    }

    public void test_setSendBufferSizeI() throws Exception {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server.getLocalPort());
        client.setSendBufferSize(134);
        assertTrue("Incorrect buffer size", client.getSendBufferSize() >= 134);
        client.close();
        server.close();
    }

    public void test_setSocketImplFactoryLjava_net_SocketImplFactory() {
        // Cannot test as setting will cause the factory to be changed for
        // all subsequent sockets
    }

    public void test_setSoLingerZI() throws IOException {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server.getLocalPort());
        client.setSoLinger(true, 500);
        assertEquals("Set incorrect linger", 500, client.getSoLinger());
        client.setSoLinger(false, 0);
        client.close();
        server.close();
    }

    public void test_setSoTimeoutI() throws Exception {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server.getLocalPort());
        final int timeoutSet = 100;
        client.setSoTimeout(timeoutSet);
        int actualTimeout = client.getSoTimeout();
        // The kernel can round the requested value based on the HZ setting. We allow up to 10ms.
        assertTrue("Set incorrect sotimeout", Math.abs(timeoutSet - actualTimeout) <= 10);
        client.close();
        server.close();
    }

    public void test_setTcpNoDelayZ() throws Exception {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server.getLocalPort());

        boolean bool;
        client.setTcpNoDelay(bool = !client.getTcpNoDelay());
        assertTrue("Failed to set no delay setting: " + client.getTcpNoDelay(), client.getTcpNoDelay() == bool);

        client.close();
        server.close();
    }

    public void test_setTrafficClassI() throws Exception {
        int IPTOS_LOWCOST = 0x2;
        int IPTOS_RELIABILTY = 0x4;
        int IPTOS_THROUGHPUT = 0x8;
        int IPTOS_LOWDELAY = 0x10;

        Socket theSocket = new Socket();

        // validate that value set must be between 0 and 255
        try {
            theSocket.setTrafficClass(256);
            fail("No exception was thrown when traffic class set to 256");
        } catch (IllegalArgumentException expected) {
        }

        try {
            theSocket.setTrafficClass(-1);
            fail("No exception was thrown when traffic class set to -1");
        } catch (IllegalArgumentException expected) {
        }

        // now validate that we can set it to some good values
        theSocket.setTrafficClass(IPTOS_LOWCOST);
        theSocket.setTrafficClass(IPTOS_RELIABILTY);
        theSocket.setTrafficClass(IPTOS_THROUGHPUT);
        theSocket.setTrafficClass(IPTOS_LOWDELAY);
    }

    @SuppressWarnings("deprecation")
    public void test_shutdownInput() throws IOException {
        ServerSocket server = new ServerSocket(0);
        int port = server.getLocalPort();
        Socket client = new Socket(InetAddress.getLocalHost(), port);

        Socket worker = server.accept();
        worker.setTcpNoDelay(true);

        InputStream theInput = client.getInputStream();
        OutputStream theOutput = worker.getOutputStream();

        // shutdown the input
        client.shutdownInput();

        // send the regular data
        String sendString = "Test";
        theOutput.write(sendString.getBytes());
        theOutput.flush();

        // RI fails here. It is a RI bug not to return 0 to indicate EOF
        assertEquals(0, theInput.available());

        client.close();
        server.close();

        // Regression test for HARMONY-2944
        // Port 0 is not allowed to be used in connect() on some platforms,
        // Since server has been closed here, so the port is free now
        Socket s = new Socket("0.0.0.0", port, false);
        s.shutdownInput();
        try {
            s.shutdownInput();
            fail("should throw SocketException");
        } catch (SocketException se) {
            // Expected
        }
        s.close();
    }

    /**
     * java.net.Socket#shutdownOutput()
     */
    @SuppressWarnings("deprecation")
    public void test_shutdownOutput() throws IOException {
        ServerSocket server = new ServerSocket(0);
        int port = server.getLocalPort();
        Socket client = new Socket(InetAddress.getLocalHost(), port);

        Socket worker = server.accept();
        OutputStream theOutput = worker.getOutputStream();

        // shutdown the output
        worker.shutdownOutput();

        // send the regular data
        String sendString = "Test";
        try {
            theOutput.write(sendString.getBytes());
            theOutput.flush();
            fail("No exception when writing on socket with output shutdown");
        } catch (IOException e) {
            // Expected
        }

        client.close();
        server.close();

        // Regression test for HARMONY-2944
        // Port 0 is not allowed to be used in connect() on some platforms,
        // Since server has been closed here, so the port is free now
        Socket s = new Socket("0.0.0.0", port, false);
        s.shutdownOutput();
        try {
            s.shutdownOutput();
            fail("should throw SocketException");
        } catch (SocketException se) {
            // Expected
        }
        s.close();
    }

    public void test_toString() throws IOException {
        ServerSocket server = new ServerSocket(0);
        Socket client = new Socket(InetAddress.getLocalHost(), server.getLocalPort());
        // RI has "addr" and "localport" instead of "address" and "localPort".
        String expected = "Socket[address=" + InetAddress.getLocalHost()
                + ",port=" + client.getPort() + ",localPort="
                + client.getLocalPort() + "]";
        assertEquals(expected, client.toString());
        client.close();
        server.close();
    }
}