1 /***
2 *
3 * Copyright 2004 Protique Ltd
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 **/
18 package org.codehaus.activemq.store.bdb;
19
20 import com.sleepycat.je.DatabaseConfig;
21 import com.sleepycat.je.DatabaseException;
22 import com.sleepycat.je.Environment;
23 import com.sleepycat.je.EnvironmentConfig;
24 import com.sleepycat.je.Transaction;
25 import org.apache.commons.logging.Log;
26 import org.apache.commons.logging.LogFactory;
27
28 import java.io.File;
29 import java.util.LinkedList;
30
31 /***
32 * Some helper factory methods for creating default configured Berkeley DB objects
33 *
34 * @version $Revision: 1.2 $
35 */
36 public class BDbHelper {
37 private static final Log log = LogFactory.getLog(BDbHelper.class);
38 private static ThreadLocal threadLocalTxn = new ThreadLocal();
39
40 public static Environment createEnvironment(File dir) throws DatabaseException {
41 dir.mkdirs();
42 EnvironmentConfig envConfig = new EnvironmentConfig();
43 envConfig.setAllowCreate(true);
44 envConfig.setTransactional(true);
45 return new Environment(dir, envConfig);
46 }
47
48 public static DatabaseConfig createDatabaseConfig() {
49 DatabaseConfig config = new DatabaseConfig();
50 config.setTransactional(true);
51 config.setAllowCreate(true);
52 return config;
53 }
54
55 /***
56 * @return the current thread local transaction that is in progress or null if there is no
57 * transaction in progress
58 */
59 public static Transaction getTransaction() {
60 LinkedList list = (LinkedList) threadLocalTxn.get();
61 if (list != null && !list.isEmpty()) {
62 return (Transaction) list.getFirst();
63 }
64 return null;
65 }
66
67 /***
68 * Pops off the current transaction from the stack
69 */
70 public static Transaction popTransaction() {
71 LinkedList list = (LinkedList) threadLocalTxn.get();
72 if (list == null || list.isEmpty()) {
73 log.warn("Attempt to pop transaction when no transaction in progress");
74 return null;
75 }
76 else {
77 return (Transaction) list.removeFirst();
78 }
79 }
80
81 /***
82 * Sets the current transaction, possibly including nesting
83 */
84 public static void pushTransaction(Transaction transaction) {
85 LinkedList list = (LinkedList) threadLocalTxn.get();
86 if (list == null) {
87 list = new LinkedList();
88 threadLocalTxn.set(list);
89 }
90 list.addLast(transaction);
91 }
92
93 public static int getTransactionCount() {
94 LinkedList list = (LinkedList) threadLocalTxn.get();
95 if (list != null) {
96 return list.size();
97 }
98 return 0;
99 }
100
101 public static byte[] asBytes(long v) {
102 byte[] data = new byte[8];
103 data[0] = (byte) (v >>> 56);
104 data[1] = (byte) (v >>> 48);
105 data[2] = (byte) (v >>> 40);
106 data[3] = (byte) (v >>> 32);
107 data[4] = (byte) (v >>> 24);
108 data[5] = (byte) (v >>> 16);
109 data[6] = (byte) (v >>> 8);
110 data[7] = (byte) (v >>> 0);
111 return data;
112 }
113
114 public static byte[] asBytes(Long key) {
115 long v = key.longValue();
116 return asBytes(v);
117 }
118
119 public static long longFromBytes(byte[] data) {
120 return (((long) data[0] << 56) +
121 ((long) (data[1] & 255) << 48) +
122 ((long) (data[2] & 255) << 40) +
123 ((long) (data[3] & 255) << 32) +
124 ((long) (data[4] & 255) << 24) +
125 ((data[5] & 255) << 16) +
126 ((data[6] & 255) << 8) +
127 ((data[7] & 255) << 0));
128 }
129
130 }