package com.atlassian.sal.core.net;
   
   import java.io.IOException;
   import java.net.InetAddress;
   import java.net.Socket;
   import java.net.UnknownHostException;
   import java.security.NoSuchAlgorithmException;
   import java.util.Arrays;
   
  import javax.net.ssl.SSLContext;
  import javax.net.ssl.SSLSocket;
  
  import org.apache.commons.httpclient.ConnectTimeoutException;
  import org.apache.commons.httpclient.params.HttpConnectionParams;
  import org.apache.commons.httpclient.protocol.SSLProtocolSocketFactory;
  
  /**
   * A custom SecureProtocolSocketFactory that uses JSSE to create sockets.
   * <p/>
   * This factory handles the JSSE system property "https.protocols" used to specify which protocol suites to enable.
   * http://docs.oracle.com/javase/7/docs/technotes/guides/security/jsse/JSSERefGuide.html#Customization
   */
  class CustomSSLProtocolSocketFactory extends SSLProtocolSocketFactory
  {
      private final String[] protocols;
  
      /**
       * Creates CustomSSLProtocolSocketFactory.
       * Uses the "https.protocols" system property if defined otherwise uses protocols parameter.
       *
       * Available protocols:
       * http://docs.oracle.com/javase/1.5.0/docs/guide/security/jsse/JSSERefGuide.html#AppA
       *
       * @param protocols Comma-separated list of protocol versions enabled for use on socket created by this factory.
       */
      public CustomSSLProtocolSocketFactory(String protocols)
      {
          String protocolsProperty = System.getProperty("https.protocols", protocols);
          if (protocolsProperty == null)
          {
              protocolsProperty = getSupportedTLSProtocols();
          }
          this.protocols = protocolsProperty.split(",");
      }
  
      /**
       * Returns a String of supported TLS protocols delimited by ',' - TLSv1.0 is the earliest supported version.
       * @return a String of supported TLS protocols delimited by ',' - TLSv1.0 is the earliest supported version.
       */
      public static String getSupportedTLSProtocols()
      {
          StringBuilder sb = new StringBuilder();
          try
          {
              for (String protocol: SSLContext.getDefault()
                  .getSupportedSSLParameters().getProtocols())
              {
                  if (protocol.startsWith("TLS"))
                  {
                      sb.append(protocol).append(",");
                  }
              }
          }
          catch (NoSuchAlgorithmException e)
          {
              throw new RuntimeException(e);
          }
          String protocols = sb.toString();
          if (protocols.endsWith(","))
          {
              protocols = protocols.substring(0, protocols.length() - 1);
          }
          return protocols;
      }
  
      @Override
      protected void setSSLProtocols(SSLSocket socket)
      {
          setSocketProtocols(socket);
      }
  
      private void setSocketProtocols(Socket socket)
      {
          SSLSocket sslSocket = (SSLSocket) socket;
          sslSocket.setEnabledProtocols(protocols);
      }
  
      @Override
      public Socket createSocket(final String host, final int port, final InetAddress clientHost, final int clientPort)
              throws IOException, UnknownHostException
      {
          Socket socket = super.createSocket(host, port, clientHost, clientPort);
          setSocketProtocols(socket);
          return socket;
      }
  
      @Override
      public Socket createSocket(final String host, final int port, final InetAddress localAddress, final int localPort, final HttpConnectionParams params)
              throws IOException, UnknownHostException, ConnectTimeoutException
     {
         Socket socket = super.createSocket(host, port, localAddress, localPort, params);
         setSocketProtocols(socket);
         return socket;
     }
 
     @Override
     public Socket createSocket(final String host, final int port) throws IOException, UnknownHostException
     {
         Socket socket = super.createSocket(host, port);
         setSocketProtocols(socket);
         return socket;
     }
 
     @Override
     public Socket createSocket(final Socket socket, final String host, final int port, final boolean autoClose)
             throws IOException, UnknownHostException
     {
         Socket newSocket = super.createSocket(socket, host, port, autoClose);
         setSocketProtocols(newSocket);
         return newSocket;
     }
 
     public String[] getProtocols()
     {
         return protocols;
     }
 
     @Override
     public boolean equals(Object o)
     {
         if (this == o)
         {
             return true;
         }
         if (o == null || getClass() != o.getClass())
         {
             return false;
         }
         if (!super.equals(o))
         {
             return false;
         }
 
         CustomSSLProtocolSocketFactory that = (CustomSSLProtocolSocketFactory) o;
         if (!Arrays.equals(protocols, that.protocols))
         {
             return false;
         }
 
         return true;
     }
 
     @Override
     public int hashCode()
     {
         int result = super.hashCode();
         result = 31 * result + (protocols != null ? Arrays.hashCode(protocols) : 0);
         return result;
     }
 }