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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *     http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing, software
13   * distributed under the License is distributed on an "AS IS" BASIS,
14   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15   * See the License for the specific language governing permissions and
16   * limitations under the License.
17   *
18   */
19  
20  package org.apache.hadoop.hbase.ipc;
21  
22  import com.google.protobuf.Descriptors;
23  import com.google.protobuf.Message;
24  import org.apache.hadoop.hbase.classification.InterfaceAudience;
25  import org.apache.hadoop.hbase.protobuf.generated.ClientProtos;
26  import org.apache.hadoop.hbase.util.ByteStringer;
27  
28  /**
29   * Utilities for handling coprocessor service calls.
30   */
31  @InterfaceAudience.Private
32  public final class CoprocessorRpcUtils {
33    /**
34     * We assume that all HBase protobuf services share a common package name
35     * (defined in the .proto files).
36     */
37    private static String hbaseServicePackage;
38    static {
39      Descriptors.ServiceDescriptor clientService = ClientProtos.ClientService.getDescriptor();
40      hbaseServicePackage = clientService.getFullName()
41          .substring(0, clientService.getFullName().lastIndexOf(clientService.getName()));
42    }
43  
44    private CoprocessorRpcUtils() {
45      // private for utility class
46    }
47  
48    /**
49     * Returns the name to use for coprocessor service calls.  For core HBase services
50     * (in the hbase.pb protobuf package), this returns the unqualified name in order to provide
51     * backward compatibility across the package name change.  For all other services,
52     * the fully-qualified service name is used.
53     */
54    public static String getServiceName(Descriptors.ServiceDescriptor service) {
55      if (service.getFullName().startsWith(hbaseServicePackage)) {
56        return service.getName();
57      }
58      return service.getFullName();
59    }
60  
61    /**
62     * Returns a service call instance for the given coprocessor request.
63     */
64    public static ClientProtos.CoprocessorServiceCall buildServiceCall(byte[] row,
65        Descriptors.MethodDescriptor method, Message request) {
66      return ClientProtos.CoprocessorServiceCall.newBuilder()
67          .setRow(ByteStringer.wrap(row))
68          .setServiceName(CoprocessorRpcUtils.getServiceName(method.getService()))
69          .setMethodName(method.getName())
70          .setRequest(request.toByteString()).build();
71    }
72  }