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.tools.protocolPB;
020    
021    import java.io.Closeable;
022    import java.io.IOException;
023    import org.apache.hadoop.ipc.ProtobufHelper;
024    import org.apache.hadoop.ipc.ProtocolMetaInterface;
025    import org.apache.hadoop.ipc.RPC;
026    import org.apache.hadoop.ipc.RpcClientUtil;
027    import org.apache.hadoop.tools.GetUserMappingsProtocol;
028    import org.apache.hadoop.tools.proto.GetUserMappingsProtocolProtos.GetGroupsForUserRequestProto;
029    import org.apache.hadoop.tools.proto.GetUserMappingsProtocolProtos.GetGroupsForUserResponseProto;
030    
031    import com.google.protobuf.RpcController;
032    import com.google.protobuf.ServiceException;
033    
034    public class GetUserMappingsProtocolClientSideTranslatorPB implements
035        ProtocolMetaInterface, GetUserMappingsProtocol, Closeable {
036    
037      /** RpcController is not used and hence is set to null */
038      private final static RpcController NULL_CONTROLLER = null;
039      private final GetUserMappingsProtocolPB rpcProxy;
040      
041      public GetUserMappingsProtocolClientSideTranslatorPB(
042          GetUserMappingsProtocolPB rpcProxy) {
043        this.rpcProxy = rpcProxy;
044      }
045    
046      @Override
047      public void close() throws IOException {
048        RPC.stopProxy(rpcProxy);
049      }
050    
051      @Override
052      public String[] getGroupsForUser(String user) throws IOException {
053        GetGroupsForUserRequestProto request = GetGroupsForUserRequestProto
054            .newBuilder().setUser(user).build();
055        GetGroupsForUserResponseProto resp;
056        try {
057          resp = rpcProxy.getGroupsForUser(NULL_CONTROLLER, request);
058        } catch (ServiceException se) {
059          throw ProtobufHelper.getRemoteException(se);
060        }
061        return resp.getGroupsList().toArray(new String[resp.getGroupsCount()]);
062      }
063    
064      @Override
065      public boolean isMethodSupported(String methodName) throws IOException {
066        return RpcClientUtil.isMethodSupported(rpcProxy,
067            GetUserMappingsProtocolPB.class, RPC.RpcKind.RPC_PROTOCOL_BUFFER,
068            RPC.getProtocolVersion(GetUserMappingsProtocolPB.class), methodName);
069      }
070    }