001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements.  See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership.  The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the
007     * "License"); you may not use this file except in compliance
008     * with the License.  You may obtain a copy of the License at
009     *
010     *     http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing, software
013     * distributed under the License is distributed on an "AS IS" BASIS,
014     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    
019    package org.apache.hadoop.yarn.api.protocolrecords;
020    
021    import java.nio.ByteBuffer;
022    import java.util.Map;
023    
024    import org.apache.hadoop.classification.InterfaceAudience.Public;
025    import org.apache.hadoop.classification.InterfaceStability.Stable;
026    import org.apache.hadoop.yarn.api.ContainerManager;
027    
028    /**
029     * <p>The response sent by the <code>NodeManager</code> to the 
030     * <code>ApplicationMaster</code> when asked to <em>start</em> an
031     * allocated container.</p>
032     * 
033     * @see ContainerManager#startContainer(StartContainerRequest)
034     */
035    @Public
036    @Stable
037    public interface StartContainerResponse {
038      /**
039       * <p>Get the responses from all auxiliary services running on the 
040       * <code>NodeManager</code>.</p>
041       * <p>The responses are returned as a Map between the auxiliary service names
042       * and their corresponding opaque blob <code>ByteBuffer</code>s</p> 
043       * @return a Map between the auxiliary service names and their outputs
044       */
045      Map<String, ByteBuffer> getAllServiceResponse();
046    
047      /**
048       * Get the response from a single auxiliary service running on the
049       * <code>NodeManager</code>
050       * 
051       * @param key The auxiliary service name whose response is desired.
052       * @return The opaque blob <code>ByteBuffer</code> returned by the auxiliary
053       * service.
054       */
055      ByteBuffer getServiceResponse(String key);
056    
057      /**
058       * Add to the list of auxiliary services which have been started on the
059       * <code>NodeManager</code>. This is done only once when the
060       * <code>NodeManager</code> starts up
061       * @param serviceResponse A map from auxiliary service names to the opaque
062       * blob <code>ByteBuffer</code>s for that auxiliary service
063       */
064      void addAllServiceResponse(Map<String, ByteBuffer> serviceResponse);
065    
066      /**
067       * Add to the list of auxiliary services which have been started on the
068       * <code>NodeManager</code>. This is done only once when the
069       * <code>NodeManager</code> starts up
070       * 
071       * @param key The auxiliary service name
072       * @param value The opaque blob <code>ByteBuffer</code> managed by the
073       * auxiliary service
074       */
075      void setServiceResponse(String key, ByteBuffer value);
076    
077      /**
078       * Remove a single auxiliary service from the StartContainerResponse object
079       * @param key The auxiliary service to remove
080       */
081      void removeServiceResponse(String key);
082      
083      /**
084       * Remove all the auxiliary services from the StartContainerResponse object
085       */
086      void clearServiceResponse();
087    }