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 * to you under the Apache License, Version 2.0 (the
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package org.apache.http.conn;

import java.io.IOException;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.SocketTimeoutException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;

import org.apache.http.annotation.Contract;
import org.apache.http.annotation.ThreadingBehavior;
import org.apache.http.conn.scheme.SocketFactory;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpParams;
import org.apache.http.util.Args;
import org.apache.http.util.Asserts;

Socket factory that implements a simple multi-home fail-over on connect failure, provided the same hostname resolves to multiple InetAddresses. Please note the connectSocket(Socket, String, int, InetAddress, int, HttpParams) method cannot be reliably interrupted by closing the socket returned by the createSocket() method. 
Since:
4.0
Deprecated:
(4.1) Do not use. For multihome support socket factories must implement SchemeSocketFactory interface./**
 * Socket factory that implements a simple multi-home fail-over on connect failure,
 * provided the same hostname resolves to multiple {@link InetAddress}es. Please note
 * the {@link #connectSocket(Socket, String, int, InetAddress, int, HttpParams)}
 * method cannot be reliably interrupted by closing the socket returned by the
 * {@link #createSocket()} method.
 *
 * @since 4.0
 *
 * @deprecated (4.1)  Do not use. For multihome support socket factories must implement
 * {@link org.apache.http.conn.scheme.SchemeSocketFactory} interface.
 */
@Deprecated
@Contract(threading = ThreadingBehavior.IMMUTABLE)
public final class MultihomePlainSocketFactory implements SocketFactory {

    
The factory singleton.
/**
     * The factory singleton.
     */
    private static final
    MultihomePlainSocketFactory DEFAULT_FACTORY = new MultihomePlainSocketFactory();

    
Gets the singleton instance of this class.
Returns:
the one and only plain socket factory/**
     * Gets the singleton instance of this class.
     * @return the one and only plain socket factory
     */
    public static MultihomePlainSocketFactory getSocketFactory() {
        return DEFAULT_FACTORY;
    }

    
Restricted default constructor.
/**
     * Restricted default constructor.
     */
    private MultihomePlainSocketFactory() {
        super();
    }


    // non-javadoc, see interface org.apache.http.conn.SocketFactory
    @Override
    public Socket createSocket() {
        return new Socket();
    }

    
Attempts to connects the socket to any of the InetAddresses the given host name resolves to. If connection to all addresses fail, the last I/O exception is propagated to the caller. 
Params:
socket – socket to connect to any of the given addresses
host – Host name to connect to
port – the port to connect to
localAddress – local address
localPort – local port
params – HTTP parameters
Throws:
IOException – if an error occurs during the connection
SocketTimeoutException – if timeout expires before connecting/**
     * Attempts to connects the socket to any of the {@link InetAddress}es the
     * given host name resolves to. If connection to all addresses fail, the
     * last I/O exception is propagated to the caller.
     *
     * @param socket socket to connect to any of the given addresses
     * @param host Host name to connect to
     * @param port the port to connect to
     * @param localAddress local address
     * @param localPort local port
     * @param params HTTP parameters
     *
     * @throws  IOException if an error occurs during the connection
     * @throws  SocketTimeoutException if timeout expires before connecting
     */
    @Override
    public Socket connectSocket(final Socket socket, final String host, final int port,
                                final InetAddress localAddress, final int localPort,
                                final HttpParams params)
        throws IOException {
        Args.notNull(host, "Target host");
        Args.notNull(params, "HTTP parameters");

        Socket sock = socket;
        if (sock == null) {
            sock = createSocket();
        }

        if ((localAddress != null) || (localPort > 0)) {
            final InetSocketAddress isa = new InetSocketAddress(localAddress,
                    localPort > 0 ? localPort : 0);
            sock.bind(isa);
        }

        final int timeout = HttpConnectionParams.getConnectionTimeout(params);

        final InetAddress[] inetadrs = InetAddress.getAllByName(host);
        final List<InetAddress> addresses = new ArrayList<InetAddress>(inetadrs.length);
        addresses.addAll(Arrays.asList(inetadrs));
        Collections.shuffle(addresses);

        IOException lastEx = null;
        for (final InetAddress remoteAddress: addresses) {
            try {
                sock.connect(new InetSocketAddress(remoteAddress, port), timeout);
                break;
            } catch (final SocketTimeoutException ex) {
                throw new ConnectTimeoutException("Connect to " + remoteAddress + " timed out");
            } catch (final IOException ex) {
                // create new socket
                sock = new Socket();
                // keep the last exception and retry
                lastEx = ex;
            }
        }
        if (lastEx != null) {
            throw lastEx;
        }
        return sock;
    } // connectSocket


    
Checks whether a socket connection is secure.
This factory creates plain socket connections
which are not considered secure.
Params:
sock –      the connected socket
Throws:
IllegalArgumentException – if the argument is invalid
Returns:
 false/**
     * Checks whether a socket connection is secure.
     * This factory creates plain socket connections
     * which are not considered secure.
     *
     * @param sock      the connected socket
     *
     * @return  {@code false}
     *
     * @throws IllegalArgumentException if the argument is invalid
     */
    @Override
    public final boolean isSecure(final Socket sock)
        throws IllegalArgumentException {

        Args.notNull(sock, "Socket");
        // This check is performed last since it calls a method implemented
        // by the argument object. getClass() is final in java.lang.Object.
        Asserts.check(!sock.isClosed(), "Socket is closed");
        return false;

    } // isSecure

}