/**
* 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.
*/
package org.apache.drill.exec.physical.impl;
import org.apache.drill.exec.proto.ExecProtos.FragmentHandle;
/**
* A FragmentRoot is a node which is the last processing node in a query plan. FragmentTerminals include Exchange
* output nodes and storage nodes. They are there driving force behind the completion of a query.
*/
public interface RootExec extends AutoCloseable {
/**
* Do the next batch of work.
* @return Whether or not additional batches of work are necessary. False means that this fragment is done.
*/
public boolean next();
/**
* Inform sender that receiving fragment is finished and doesn't need any more data
* @param handle
*/
public void receivingFragmentFinished(FragmentHandle handle);
}