gcc/libjava/classpath/gnu/CORBA/IOR_Delegate.java

/* gnuDelegate.java --
   Copyright (C) 2005 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Classpath is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

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02110-1301 USA.

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making a combined work based on this library.  Thus, the terms and
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permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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this exception to your version of the library, but you are not
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exception statement from your version. */


package gnu.CORBA;

import gnu.CORBA.CDR.cdrBufInput;
import gnu.CORBA.GIOP.ReplyHeader;
import gnu.CORBA.Poa.activeObjectMap;

import org.omg.CORBA.CompletionStatus;
import org.omg.CORBA.Context;
import org.omg.CORBA.ContextList;
import org.omg.CORBA.ExceptionList;
import org.omg.CORBA.MARSHAL;
import org.omg.CORBA.NVList;
import org.omg.CORBA.NamedValue;
import org.omg.CORBA.ORB;
import org.omg.CORBA.Request;
import org.omg.CORBA.portable.ApplicationException;
import org.omg.CORBA.portable.InputStream;
import org.omg.CORBA.portable.OutputStream;
import org.omg.CORBA.portable.RemarshalException;
import org.omg.PortableInterceptor.ForwardRequest;

import java.io.IOException;

import java.net.Socket;

/**
 * The Classpath implementation of the {@link Delegate} functionality in the
 * case, when the object was constructed from an IOR object. The IOR can be
 * constructed from the stringified object reference.
 *
 * There is an different instance of this delegate for each CORBA object.
 *
 * @author Audrius Meskauskas (AudriusA@Bioinformatics.org)
 */
public class IOR_Delegate extends Simple_delegate
{
  /**
   * True if the current IOR does not map into the local servant. If false, the
   * IOR is either local or should be checked.
   */
  boolean remote_ior;

  /**
   * If not null, this field contains data about the local servant.
   */
  activeObjectMap.Obj local_ior;

  /**
   * Contructs an instance of object using the given IOR.
   */
  public IOR_Delegate(ORB an_orb, IOR an_ior)
  {
    super(an_orb, an_ior);
  }

  /**
   * Creates the request to invoke the method on this object.
   *
   * @param target the object, for that the operation must be invoked.
   * @param context context (null allowed)
   * @param operation the method name
   * @param parameters the method parameters
   * @param returns the return value holder
   * @param exceptions the exceptions that can be thrown by the method
   * @param ctx_list the context list (null allowed)
   *
   * @return the created request.
   */
  public Request create_request(org.omg.CORBA.Object target, Context context,
    String operation, NVList parameters, NamedValue returns
  )
  {
    gnuRequest request = getRequestInstance(target);

    request.setIor(getIor());
    request.set_target(target);

    request.setOperation(operation);
    request.set_args(parameters);
    request.m_context = context;
    request.set_result(returns);
    request.setORB(orb);

    return request;
  }

  /**
   * Creates the request to invoke the method on this object.
   *
   * @param target the object, for that the operation must be invoked.
   * @param context context (null allowed)
   * @param operation the method name
   * @param parameters the method parameters
   * @param returns the return value holder
   *
   * @return the created request.
   */
  public Request create_request(org.omg.CORBA.Object target, Context context,
    String operation, NVList parameters, NamedValue returns,
    ExceptionList exceptions, ContextList ctx_list
  )
  {
    gnuRequest request = getRequestInstance(target);

    request.setIor(ior);
    request.set_target(target);

    request.setOperation(operation);
    request.set_args(parameters);
    request.m_context = context;
    request.set_result(returns);
    request.set_exceptions(exceptions);
    request.set_context_list(ctx_list);
    request.setORB(orb);

    return request;
  }

  /**
   * Get the instance of request.
   */
  protected gnuRequest getRequestInstance(org.omg.CORBA.Object target)
  {
    return new gnuRequest();
  }

  /**
   * Invoke operation on the given object, als handling temproray and permanent
   * redirections. The ReplyHeader.LOCATION_FORWARD will cause to resend the
   * request to the new direction. The ReplyHeader.LOCATION_FORWARD_PERM will
   * cause additionally to remember the new location by this delegate, so
   * subsequent calls will be immediately delivered to the new target.
   *
   * @param target the target object.
   * @param output the output stream, previously returned by
   * {@link #request(org.omg.CORBA.Object, String, boolean)}.
   *
   * @return the input stream, to read the response from or null for a one-way
   * request.
   *
   * @throws SystemException if the SystemException has been thrown on the
   * remote side (the exact type and the minor code matches the data of the
   * remote exception that has been thrown).
   *
   * @throws org.omg.CORBA.portable.ApplicationException as specified.
   * @throws org.omg.CORBA.portable.RemarshalException as specified.
   */
  public InputStream invoke(org.omg.CORBA.Object target, OutputStream output)
    throws ApplicationException, RemarshalException
  {
    streamRequest request = (streamRequest) output;
    Forwardings:
    while (true)
      {
        try
          {
            if (request.response_expected)
              {
                binaryReply response = request.request.submit();

                // Read reply header.
                ReplyHeader rh = response.header.create_reply_header();
                cdrBufInput input = response.getStream();
                input.setOrb(orb);
                rh.read(input);
                request.request.m_rph = rh;

                boolean moved_permanently = false;

                switch (rh.reply_status)
                  {
                    case ReplyHeader.NO_EXCEPTION :
                      if (request.request.m_interceptor != null)
                        request.request.m_interceptor.
                          receive_reply(request.request.m_info);
                      if (response.header.version.since_inclusive(1, 2))
                        input.align(8);
                      return input;

                    case ReplyHeader.SYSTEM_EXCEPTION :
                      if (response.header.version.since_inclusive(1, 2))
                        input.align(8);
                      showException(request, input);

                      throw ObjectCreator.readSystemException(input);

                    case ReplyHeader.USER_EXCEPTION :
                      if (response.header.version.since_inclusive(1, 2))
                        input.align(8);
                      showException(request, input);

                      throw new ApplicationException(request.
                        request.m_exception_id, input
                      );

                    case ReplyHeader.LOCATION_FORWARD_PERM :
                      moved_permanently = true;

                    case ReplyHeader.LOCATION_FORWARD :
                      if (response.header.version.since_inclusive(1, 2))
                        input.align(8);

                      IOR forwarded = new IOR();
                      try
                        {
                          forwarded._read_no_endian(input);
                        }
                      catch (IOException ex)
                        {
                          MARSHAL t =
                            new MARSHAL("Cant read forwarding info", 5102,
                              CompletionStatus.COMPLETED_NO
                            );
                          t.initCause(ex);
                          throw t;
                        }

                      gnuRequest prev = request.request;
                      gnuRequest r = getRequestInstance(target);

                      r.m_interceptor = prev.m_interceptor;
                      r.m_slots = prev.m_slots;

                      r.m_args = prev.m_args;
                      r.m_context = prev.m_context;
                      r.m_context_list = prev.m_context_list;
                      r.m_environment = prev.m_environment;
                      r.m_exceptions = prev.m_exceptions;
                      r.m_operation = prev.m_operation;
                      r.m_parameter_buffer = prev.m_parameter_buffer;
                      r.m_parameter_buffer.request = r;
                      r.m_result = prev.m_result;
                      r.m_target = prev.m_target;
                      r.oneWay = prev.oneWay;
                      r.m_forward_ior = forwarded;

                      if (r.m_interceptor != null)
                        r.m_interceptor.receive_other(r.m_info);

                      r.setIor(forwarded);

                      IOR_contructed_object it =
                        new IOR_contructed_object(orb, forwarded);

                      r.m_target = it;

                      request.request = r;

                      IOR prev_ior = getIor();

                      setIor(forwarded);

                      try
                        {
                          return invoke(it, request);
                        }
                      finally
                        {
                          if (!moved_permanently)
                            setIor(prev_ior);
                        }

                    default :
                      throw new MARSHAL("Unknow reply status: " +
                        rh.reply_status, 8000 + rh.reply_status,
                        CompletionStatus.COMPLETED_NO
                      );
                  }
              }
            else
              {
                request.request.send_oneway();
                return null;
              }
          }
        catch (ForwardRequest forwarded)
          {
            ForwardRequest fw = forwarded;
            Forwarding2:
            while (true)
              {
                try
                  {
                    gnuRequest prev = request.request;
                    gnuRequest r = getRequestInstance(target);

                    r.m_interceptor = prev.m_interceptor;
                    r.m_args = prev.m_args;
                    r.m_context = prev.m_context;
                    r.m_context_list = prev.m_context_list;
                    r.m_environment = prev.m_environment;
                    r.m_exceptions = prev.m_exceptions;
                    r.m_operation = prev.m_operation;
                    r.m_parameter_buffer = prev.m_parameter_buffer;
                    r.m_parameter_buffer.request = r;
                    r.m_result = prev.m_result;
                    r.m_target = prev.m_target;
                    r.oneWay = prev.oneWay;

                    r.m_forwarding_target = fw.forward;

                    if (r.m_interceptor != null)
                      r.m_interceptor.receive_other(r.m_info);

                    r.m_target = fw.forward;
                    request.request = r;
                    break Forwarding2;
                  }
                catch (ForwardRequest e)
                  {
                    forwarded = e;
                  }
              }
          }
      }
  }

  /**
   * Show exception to interceptor.
   */
  void showException(streamRequest request, cdrBufInput input)
    throws ForwardRequest
  {
    input.mark(2048);
    request.request.m_exception_id = input.read_string();
    input.reset();

    if (request.request.m_interceptor != null)
      request.request.m_interceptor.receive_exception(request.request.m_info);
  }

  /**
   * Create a request to invoke the method of this CORBA object.
   *
   * @param target the CORBA object, to that this operation must be applied.
   * @param operation the name of the method to invoke.
   *
   * @return the request.
   */
  public Request request(org.omg.CORBA.Object target, String operation)
  {
    gnuRequest request = getRequestInstance(target);

    request.setIor(ior);
    request.set_target(target);

    request.setOperation(operation);
    request.setORB(orb);

    return request;
  }

  /**
   * Create a request to invoke the method of this CORBA object.
   *
   * @param target the CORBA object, to that this operation must be applied.
   * @param operation the name of the method to invoke.
   * @param response_expected specifies if this is one way message or the
   * response to the message is expected.
   *
   * @return the stream where the method arguments should be written.
   */
  public OutputStream request(org.omg.CORBA.Object target, String operation,
    boolean response_expected
  )
  {
    gnuRequest request = getRequestInstance(target);

    request.setIor(ior);
    request.set_target(target);
    request.setOperation(operation);

    streamRequest out = request.getParameterStream();
    out.response_expected = response_expected;
    request.setORB(orb);

    return out;
  }

  /**
   * If there is an opened cache socket to access this object, close that
   * socket.
   *
   * @param target The target is not used, this delegate requires a single
   * instance per object.
   */
  public void release(org.omg.CORBA.Object target)
  {
    String key = ior.Internet.host + ":" + ior.Internet.port;

    Socket socket = SocketRepository.get_socket(key);
    try
      {
        if (socket != null)
          {
            socket.close();
          }
      }
    catch (IOException ex)
      {
        // do nothing, then.
      }
  }

  /**
   * Reset the remote_ior flag, forcing to check if the object is local on the
   * next getRequestInstance call.
   */
  public void setIor(IOR an_ior)
  {
    super.setIor(an_ior);
    remote_ior = false;
    local_ior = null;
  }

  /**
   * Checks if the ior is local so far it is easy.
   */
  public boolean is_local(org.omg.CORBA.Object self)
  {
    if (remote_ior)
      return false;
    else if (local_ior != null)
      return true;
    else
      return super.is_local(self);
  }
}