* Licensed to the Apache Software Foundation (ASF) under one

* or more contributor license agreements.  See the NOTICE file

* distributed with this work for additional information

* regarding copyright ownership.  The ASF licenses this file

* to you under the Apache License, Version 2.0 (the

* "License"); you may not use this file except in compliance

* with the License.  You may obtain a copy of the License at

*

* http://www.apache.org/licenses/LICENSE-2.0

*

* Unless required by applicable law or agreed to in writing, software

* distributed under the License is distributed on an "AS IS" BASIS,

* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

* See the License for the specific language governing permissions and

* limitations under the License.

*/

* This handler receives all incoming traffic for a particular FragmentHandle.  It will monitor the state of incoming batches

*/

  private final PlanFragment fragment;

  private FragmentLeaf root;

  private final IncomingBuffers buffers;

  private final FragmentRunnerListener runnerListener;

  private volatile FragmentRunner runner;

  private volatile boolean cancel = false;

  private final FragmentContext context;

  private final PhysicalPlanReader reader;

 

  public RemoteFragmentHandler(PlanFragment fragment, DrillbitContext context, BitTunnel foremanTunnel) throws FragmentSetupException{

    try{

      this.fragment = fragment;

      this.root = context.getPlanReader().readFragmentOperator(fragment.getFragmentJson());

      this.buffers = new IncomingBuffers(root);

      this.context = new FragmentContext(context, fragment.getHandle(), null, buffers, new FunctionImplementationRegistry(context.getConfig()));

      this.runnerListener = new RemoteFragmentRunnerListener(this.context, foremanTunnel);

      this.reader = context.getPlanReader();

     

    }catch(IOException e){

      throw new FragmentSetupException("Failure while decoding fragment.", e);

    }

  }

  /* (non-Javadoc)

   * @see org.apache.drill.exec.work.fragment.FragmentHandler#handle(org.apache.drill.exec.rpc.RemoteConnection.ConnectionThrottle, org.apache.drill.exec.record.RawFragmentBatch)

   */

  @Override

  public boolean handle(ConnectionThrottle throttle, RawFragmentBatch batch) throws FragmentSetupException {

    return buffers.batchArrived(throttle, batch);

  }

  /* (non-Javadoc)

   * @see org.apache.drill.exec.work.fragment.FragmentHandler#getRunnable()

   */

  @Override

  public FragmentRunner getRunnable(){

    synchronized(this){

      if(runner != null) throw new IllegalStateException("Get Runnable can only be run once.");

      if(cancel) return null;

      try {

        FragmentRoot fragRoot = reader.readFragmentOperator(fragment.getFragmentJson());

        RootExec exec = ImplCreator.getExec(context, fragRoot);

        runner = new FragmentRunner(context, exec, runnerListener);

        return this.runner;

      } catch (IOException | ExecutionSetupException e) {

        runnerListener.fail(fragment.getHandle(), "Failure while setting up remote fragment.", e);

        return null;

      }

    }

   

  }

  /* (non-Javadoc)

   * @see org.apache.drill.exec.work.fragment.FragmentHandler#cancel()

   */

  @Override

  public void cancel(){

    synchronized(this){

      cancel = true;

      if(runner != null){

        runner.cancel();

      }

    }

  }

  @Override

  public FragmentHandle getHandle() {

    return fragment.getHandle();

  }

  @Override

  public boolean isWaiting() {

    return !buffers.isDone() && !cancel;

  }

 

 

 

}