plugins/org.eclipse.emf.cdo.server/src/org/eclipse/emf/cdo/internal/server/protocol/LoadChunkIndication.java

/***************************************************************************
 * Copyright (c) 2004 - 2008 Eike Stepper, Germany.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 *    Eike Stepper - initial API and implementation
 *    Simon McDuff - http://bugs.eclipse.org/210868
 **************************************************************************/
package org.eclipse.emf.cdo.internal.server.protocol;

import org.eclipse.emf.cdo.common.CDODataInput;
import org.eclipse.emf.cdo.common.CDODataOutput;
import org.eclipse.emf.cdo.common.CDOProtocolConstants;
import org.eclipse.emf.cdo.common.id.CDOID;
import org.eclipse.emf.cdo.common.model.CDOClass;
import org.eclipse.emf.cdo.common.model.CDOFeature;
import org.eclipse.emf.cdo.internal.server.bundle.OM;
import org.eclipse.emf.cdo.spi.common.revision.InternalCDORevision;

import org.eclipse.net4j.util.collection.MoveableList;
import org.eclipse.net4j.util.om.trace.ContextTracer;

import java.io.IOException;

/**
 * @author Eike Stepper
 */
public class LoadChunkIndication extends CDOReadIndication
{
  private static final ContextTracer PROTOCOL_TRACER = new ContextTracer(OM.DEBUG_PROTOCOL, LoadChunkIndication.class);

  private CDOID id;

  private int version;

  private CDOFeature feature;

  private int fromIndex;

  private int toIndex;

  public LoadChunkIndication(CDOServerProtocol protocol)
  {
    super(protocol, CDOProtocolConstants.SIGNAL_LOAD_CHUNK);
  }

  @Override
  protected void indicating(CDODataInput in) throws IOException
  {
    id = in.readCDOID();
    if (PROTOCOL_TRACER.isEnabled())
    {
      PROTOCOL_TRACER.format("Read revision ID: {0}", id);
    }

    version = in.readInt();
    if (PROTOCOL_TRACER.isEnabled())
    {
      PROTOCOL_TRACER.format("Read revision version: {0}", version);
    }

    CDOClass cdoClass = in.readCDOClassRefAndResolve();
    int featureID = in.readInt();
    feature = cdoClass.getAllFeatures()[featureID];
    if (PROTOCOL_TRACER.isEnabled())
    {
      PROTOCOL_TRACER.format("Read feature: {0}", feature);
    }

    fromIndex = in.readInt();
    if (PROTOCOL_TRACER.isEnabled())
    {
      PROTOCOL_TRACER.format("Read fromIndex: {0}", fromIndex);
    }

    toIndex = in.readInt();
    if (PROTOCOL_TRACER.isEnabled())
    {
      PROTOCOL_TRACER.format("Read toIndex: {0}", toIndex);
    }
  }

  @Override
  protected void responding(CDODataOutput out) throws IOException
  {
    InternalCDORevision revision = getRevisionManager().getRevisionByVersion(id, 0, version);
    getRevisionManager().ensureChunk(revision, feature, fromIndex, toIndex + 1);

    MoveableList<Object> list = revision.getList(feature);
    for (int i = fromIndex; i <= toIndex; i++)
    {
      feature.getType().writeValue(out, list.get(i));
    }
  }
}