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 package org.apache.hadoop.hbase.backup.example;
19
20 import java.util.List;
21 import java.util.Set;
22 import java.util.TreeSet;
23
24 import org.apache.commons.logging.Log;
25 import org.apache.commons.logging.LogFactory;
26
27 /**
28 * Monitor the actual tables for which HFiles are archived for long-term retention (always kept
29 * unless ZK state changes).
30 * <p>
31 * It is internally synchronized to ensure consistent view of the table state.
32 */
33 public class HFileArchiveTableMonitor {
34 private static final Log LOG = LogFactory.getLog(HFileArchiveTableMonitor.class);
35 private final Set<String> archivedTables = new TreeSet<String>();
36
37 /**
38 * Set the tables to be archived. Internally adds each table and attempts to
39 * register it.
40 * <p>
41 * <b>Note: All previous tables will be removed in favor of these tables.<b>
42 * @param tables add each of the tables to be archived.
43 */
44 public synchronized void setArchiveTables(List<String> tables) {
45 archivedTables.clear();
46 archivedTables.addAll(tables);
47 }
48
49 /**
50 * Add the named table to be those being archived. Attempts to register the
51 * table
52 * @param table name of the table to be registered
53 */
54 public synchronized void addTable(String table) {
55 if (this.shouldArchiveTable(table)) {
56 LOG.debug("Already archiving table: " + table + ", ignoring it");
57 return;
58 }
59 archivedTables.add(table);
60 }
61
62 public synchronized void removeTable(String table) {
63 archivedTables.remove(table);
64 }
65
66 public synchronized void clearArchive() {
67 archivedTables.clear();
68 }
69
70 /**
71 * Determine if the given table should or should not allow its hfiles to be deleted in the archive
72 * @param tableName name of the table to check
73 * @return <tt>true</tt> if its store files should be retained, <tt>false</tt> otherwise
74 */
75 public synchronized boolean shouldArchiveTable(String tableName) {
76 return archivedTables.contains(tableName);
77 }
78 }