View Javadoc

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  package org.apache.hadoop.hbase.procedure2;
20  
21  import java.io.InputStream;
22  import java.io.OutputStream;
23  
24  import org.apache.hadoop.hbase.classification.InterfaceAudience;
25  import org.apache.hadoop.hbase.classification.InterfaceStability;
26  
27  /**
28   * Special procedure used as a chore.
29   * instead of bringing the Chore class in (dependencies reason),
30   * we reuse the executor timeout thread for this special case.
31   *
32   * The assumption is that procedure is used as hook to dispatch other procedures
33   * or trigger some cleanups. It does not store state in the ProcedureStore.
34   * this is just for in-memory chore executions.
35   */
36  @InterfaceAudience.Private
37  @InterfaceStability.Evolving
38  public abstract class ProcedureInMemoryChore<TEnvironment> extends Procedure<TEnvironment> {
39    protected ProcedureInMemoryChore(final int timeoutMsec) {
40      setTimeout(timeoutMsec);
41    }
42  
43    protected abstract void periodicExecute(final TEnvironment env);
44  
45    @Override
46    protected Procedure[] execute(final TEnvironment env) {
47      throw new UnsupportedOperationException();
48    }
49  
50    @Override
51    protected void rollback(final TEnvironment env) {
52      throw new UnsupportedOperationException();
53    }
54  
55    @Override
56    protected boolean abort(final TEnvironment env) {
57      throw new UnsupportedOperationException();
58    }
59  
60    @Override
61    public void serializeStateData(final OutputStream stream) {
62      throw new UnsupportedOperationException();
63    }
64  
65    @Override
66    public void deserializeStateData(final InputStream stream) {
67      throw new UnsupportedOperationException();
68    }
69  }