1   /**
2    *
3    * Licensed to the Apache Software Foundation (ASF) under one
4    * or more contributor license agreements.  See the NOTICE file
5    * distributed with this work for additional information
6    * regarding copyright ownership.  The ASF licenses this file
7    * to you under the Apache License, Version 2.0 (the
8    * "License"); you may not use this file except in compliance
9    * with the License.  You may obtain a copy of the License at
10   *
11   *     http://www.apache.org/licenses/LICENSE-2.0
12   *
13   * Unless required by applicable law or agreed to in writing, software
14   * distributed under the License is distributed on an "AS IS" BASIS,
15   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16   * See the License for the specific language governing permissions and
17   * limitations under the License.
18   */
19  package org.apache.hadoop.hbase.monitoring;
20  
21  import java.io.IOException;
22  import java.util.Map;
23  
24  import org.apache.hadoop.classification.InterfaceAudience;
25  
26  @InterfaceAudience.Private
27  public interface MonitoredTask extends Cloneable {
28    enum State {
29      RUNNING,
30      WAITING,
31      COMPLETE,
32      ABORTED;
33    }
34  
35    public abstract long getStartTime();
36    public abstract String getDescription();
37    public abstract String getStatus();
38    public abstract long getStatusTime();
39    public abstract State getState();
40    public abstract long getStateTime();
41    public abstract long getCompletionTimestamp();
42  
43    public abstract void markComplete(String msg);
44    public abstract void pause(String msg);
45    public abstract void resume(String msg);
46    public abstract void abort(String msg);
47    public abstract void expireNow();
48  
49    public abstract void setStatus(String status);
50    public abstract void setDescription(String description);
51  
52    /**
53     * Explicitly mark this status as able to be cleaned up,
54     * even though it might not be complete.
55     */
56    public abstract void cleanup();
57  
58    /**
59     * Public exposure of Object.clone() in order to allow clients to easily 
60     * capture current state.
61     * @return a copy of the object whose references will not change
62     */
63    public abstract MonitoredTask clone();
64  
65    /**
66     * Creates a string map of internal details for extensible exposure of 
67     * monitored tasks.
68     * @return A Map containing information for this task.
69     */
70    public abstract Map<String, Object> toMap() throws IOException;
71  
72    /**
73     * Creates a JSON object for parseable exposure of monitored tasks.
74     * @return An encoded JSON object containing information for this task.
75     */
76    public abstract String toJSON() throws IOException;
77  
78  }