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package org.apache.http.conn.scheme;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.UnknownHostException;

import org.apache.http.conn.ConnectTimeoutException;
import org.apache.http.params.HttpParams;

A factory for creating, initializing and connecting sockets. The factory encapsulates the logic
for establishing a socket connection.
Since:
4.1
Deprecated:
(4.3) use ConnectionSocketFactory/**
 * A factory for creating, initializing and connecting sockets. The factory encapsulates the logic
 * for establishing a socket connection.
 *
 * @since 4.1
 *
 * @deprecated (4.3) use {@link org.apache.http.conn.socket.ConnectionSocketFactory}
 */
@Deprecated
public interface SchemeSocketFactory {

    
Creates a new, unconnected socket. The socket should subsequently be passed to connectSocket(Socket, InetSocketAddress, InetSocketAddress, HttpParams). 
Params:
params –  Optional parameters. In most cases these parameters will not be required and will have no effect, as usually socket initialization should take place in the connectSocket(Socket, InetSocketAddress, InetSocketAddress, HttpParams) method. However, in rare cases one may want to pass additional parameters to this method in order to create a customized Socket instance, for instance bound to a SOCKS proxy server.
Throws:
IOException – if an I/O error occurs while creating the socket
Returns:
 a new socket/**
     * Creates a new, unconnected socket. The socket should subsequently be passed to
     * {@link #connectSocket(Socket, InetSocketAddress, InetSocketAddress, HttpParams)}.
     *
     * @param params    Optional {@link HttpParams parameters}. In most cases these parameters
     *                  will not be required and will have no effect, as usually socket
     *                  initialization should take place in the
     *                  {@link #connectSocket(Socket, InetSocketAddress, InetSocketAddress, HttpParams)}
     *                  method. However, in rare cases one may want to pass additional parameters
     *                  to this method in order to create a customized {@link Socket} instance,
     *                  for instance bound to a SOCKS proxy server.
     *
     * @return  a new socket
     *
     * @throws IOException if an I/O error occurs while creating the socket
     */
    Socket createSocket(HttpParams params) throws IOException;

    
Connects a socket to the target host with the given remote address.
 Please note that HttpInetSocketAddress class should be used in order to pass the target remote address along with the original HttpHost value used to resolve the address. The use of HttpInetSocketAddress can also ensure that no reverse DNS lookup will be performed if the target remote address was specified as an IP address. 
Params:
sock –  the socket to connect, as obtained from createSocket. null indicates that a new socket should be created and connected.
remoteAddress – the remote address to connect to.
localAddress – the local address to bind the socket to, or null for any
params –  additional parameters for connecting
Throws:
IOException – if an I/O error occurs
UnknownHostException – if the IP address of the target host
         can not be determined
ConnectTimeoutException – if the socket cannot be connected within the time limit defined in the params
See Also:
HttpInetSocketAddress
Returns:
 the connected socket. The returned object may be different from the sock argument if this factory supports a layered protocol./**
     * Connects a socket to the target host with the given remote address.
     * <p>
     * Please note that {@link org.apache.http.conn.HttpInetSocketAddress} class should
     * be used in order to pass the target remote address along with the original
     * {@link org.apache.http.HttpHost} value used to resolve the address. The use of
     * {@link org.apache.http.conn.HttpInetSocketAddress} can also ensure that no reverse
     * DNS lookup will be performed if the target remote address was specified
     * as an IP address.
     * </p>
     *
     * @param sock      the socket to connect, as obtained from
     *                  {@link #createSocket(HttpParams) createSocket}.
     *                  {@code null} indicates that a new socket
     *                  should be created and connected.
     * @param remoteAddress the remote address to connect to.
     * @param localAddress the local address to bind the socket to, or
     *                  {@code null} for any
     * @param params    additional {@link HttpParams parameters} for connecting
     *
     * @return  the connected socket. The returned object may be different
     *          from the {@code sock} argument if this factory supports
     *          a layered protocol.
     *
     * @throws IOException if an I/O error occurs
     * @throws UnknownHostException if the IP address of the target host
     *          can not be determined
     * @throws ConnectTimeoutException if the socket cannot be connected
     *          within the time limit defined in the {@code params}
     *
     * @see org.apache.http.conn.HttpInetSocketAddress
     */
    Socket connectSocket(
        Socket sock,
        InetSocketAddress remoteAddress,
        InetSocketAddress localAddress,
        HttpParams params) throws IOException, UnknownHostException, ConnectTimeoutException;

    
Checks whether a socket provides a secure connection. The socket must be connected by this factory. The factory will not perform I/O operations in this method.

As a rule of thumb, plain sockets are not secure and TLS/SSL sockets are secure. However,
there may be application specific deviations. For example, a plain socket to a host in the
same intranet ("trusted zone") could be considered secure. On the other hand, a TLS/SSL
socket could be considered insecure based on the cipher suite chosen for the connection.
Params:
sock –      the connected socket to check
Throws:
IllegalArgumentException – 
 if the argument is invalid, for example because it is
 not a connected socket or was created by a different
 socket factory.
 Note that socket factories are not required to
 check these conditions, they may simply return a default
 value when called with an invalid socket argument.
Returns:
 true if the connection of the socket should be considered secure, or false if it should not/**
     * Checks whether a socket provides a secure connection. The socket must be
     * {@link #connectSocket(Socket, InetSocketAddress, InetSocketAddress, HttpParams) connected}
     * by this factory. The factory will <i>not</i> perform I/O operations in this method.
     * <p>
     * As a rule of thumb, plain sockets are not secure and TLS/SSL sockets are secure. However,
     * there may be application specific deviations. For example, a plain socket to a host in the
     * same intranet ("trusted zone") could be considered secure. On the other hand, a TLS/SSL
     * socket could be considered insecure based on the cipher suite chosen for the connection.
     *
     * @param sock      the connected socket to check
     *
     * @return  {@code true} if the connection of the socket
     *          should be considered secure, or
     *          {@code false} if it should not
     *
     * @throws IllegalArgumentException
     *  if the argument is invalid, for example because it is
     *  not a connected socket or was created by a different
     *  socket factory.
     *  Note that socket factories are <i>not</i> required to
     *  check these conditions, they may simply return a default
     *  value when called with an invalid socket argument.
     */
    boolean isSecure(Socket sock) throws IllegalArgumentException;

}