SocksConnectionSocketFactory.java

package io.bitsquare.http;

import org.apache.http.HttpHost;
import org.apache.http.conn.socket.PlainConnectionSocketFactory;
import org.apache.http.protocol.HttpContext;

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

// This class is adapted from
//   http://stackoverflow.com/a/25203021/5616248
//
// This class routes connections over Socks, and avoids resolving hostnames locally.
class SocksConnectionSocketFactory extends PlainConnectionSocketFactory {

    /**
     * creates an unconnected Socks Proxy socket
     */
    @Override
    public Socket createSocket(final HttpContext context) throws IOException {
        InetSocketAddress socksaddr = (InetSocketAddress) context.getAttribute("socks.address");
        Proxy proxy = new Proxy(Proxy.Type.SOCKS, socksaddr);
        return new Socket(proxy);
    }

    /**
     * connects a Socks Proxy socket and passes hostname to proxy without resolving it locally.
     */
    @Override
    public Socket connectSocket(int connectTimeout, Socket socket, HttpHost host, InetSocketAddress remoteAddress,
                                InetSocketAddress localAddress, HttpContext context) throws IOException {
        // Convert address to unresolved
        InetSocketAddress unresolvedRemote = InetSocketAddress
                .createUnresolved(host.getHostName(), remoteAddress.getPort());
        return super.connectSocket(connectTimeout, socket, host, unresolvedRemote, localAddress, context);
    }
}