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: 1.1 $
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 EnvironmentConfig envConfig = new EnvironmentConfig();
42 envConfig.setAllowCreate(true);
43 envConfig.setTransactional(true);
44 return new Environment(dir, envConfig);
45 }
46
47 public static DatabaseConfig createDatabaseConfig() {
48 DatabaseConfig config = new DatabaseConfig();
49 config.setTransactional(true);
50 config.setAllowCreate(true);
51 return config;
52 }
53
54 /***
55 * @return the current thread local transaction that is in progress or null if there is no
56 * transaction in progress
57 */
58 public static Transaction getTransaction() {
59 LinkedList list = (LinkedList) threadLocalTxn.get();
60 if (list != null && !list.isEmpty()) {
61 return (Transaction) list.getFirst();
62 }
63 return null;
64 }
65
66 /***
67 * Pops off the current transaction from the stack
68 */
69 public static Transaction popTransaction() {
70 LinkedList list = (LinkedList) threadLocalTxn.get();
71 if (list == null || list.isEmpty()) {
72 log.warn("Attempt to pop transaction when no transaction in progress");
73 return null;
74 }
75 else {
76 return (Transaction) list.removeFirst();
77 }
78 }
79
80 /***
81 * Sets the current transaction, possibly including nesting
82 */
83 public static void pushTransaction(Transaction transaction) {
84 LinkedList list = (LinkedList) threadLocalTxn.get();
85 if (list == null) {
86 list = new LinkedList();
87 threadLocalTxn.set(list);
88 }
89 list.addLast(transaction);
90 }
91
92 public static int getTransactionCount() {
93 LinkedList list = (LinkedList) threadLocalTxn.get();
94 if (list != null) {
95 return list.size();
96 }
97 return 0;
98 }
99
100 public static byte[] asBytes(long v) {
101 byte[] data = new byte[8];
102 data[0] = (byte) (v >>> 56);
103 data[1] = (byte) (v >>> 48);
104 data[2] = (byte) (v >>> 40);
105 data[3] = (byte) (v >>> 32);
106 data[4] = (byte) (v >>> 24);
107 data[5] = (byte) (v >>> 16);
108 data[6] = (byte) (v >>> 8);
109 data[7] = (byte) (v >>> 0);
110 return data;
111 }
112
113 public static byte[] asBytes(Long key) {
114 long v = key.longValue();
115 return asBytes(v);
116 }
117
118 public static long longFromBytes(byte[] data) {
119 return (((long) data[0] << 56) +
120 ((long) (data[1] & 255) << 48) +
121 ((long) (data[2] & 255) << 40) +
122 ((long) (data[3] & 255) << 32) +
123 ((long) (data[4] & 255) << 24) +
124 ((data[5] & 255) << 16) +
125 ((data[6] & 255) << 8) +
126 ((data[7] & 255) << 0));
127 }
128
129 }