1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache license, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. 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.apache.logging.log4j.core.util;
19
20 import java.util.concurrent.ThreadFactory;
21 import java.util.concurrent.atomic.AtomicInteger;
22
23 /**
24 * Creates {@link Log4jThread}s.
25 *
26 * @since 2.7
27 */
28 public class Log4jThreadFactory implements ThreadFactory {
29
30 private static final String PREFIX = "TF-";
31
32 /**
33 * Creates a new daemon thread factory.
34 *
35 * @param threadFactoryName
36 * The thread factory name.
37 * @return a new daemon thread factory.
38 */
39 public static Log4jThreadFactory createDaemonThreadFactory(final String threadFactoryName) {
40 return new Log4jThreadFactory(threadFactoryName, true, Thread.NORM_PRIORITY);
41 }
42
43 /**
44 * Creates a new thread factory.
45 *
46 * This is mainly used for tests. Production code should be very careful with creating
47 * non-daemon threads since those will block application shutdown
48 * (see https://issues.apache.org/jira/browse/LOG4J2-1748).
49 *
50 * @param threadFactoryName
51 * The thread factory name.
52 * @return a new daemon thread factory.
53 */
54 public static Log4jThreadFactory createThreadFactory(final String threadFactoryName) {
55 return new Log4jThreadFactory(threadFactoryName, false, Thread.NORM_PRIORITY);
56 }
57
58 private static final AtomicInteger FACTORY_NUMBER = new AtomicInteger(1);
59 private static final AtomicInteger THREAD_NUMBER = new AtomicInteger(1);
60 private final boolean daemon;
61 private final ThreadGroup group;
62 private final int priority;
63 private final String threadNamePrefix;
64
65 /**
66 * Constructs an initialized thread factory.
67 *
68 * @param threadFactoryName
69 * The thread factory name.
70 * @param daemon
71 * Whether to create daemon threads.
72 * @param priority
73 * The thread priority.
74 */
75 public Log4jThreadFactory(final String threadFactoryName, final boolean daemon, final int priority) {
76 this.threadNamePrefix = PREFIX + FACTORY_NUMBER.getAndIncrement() + "-" + threadFactoryName + "-";
77 this.daemon = daemon;
78 this.priority = priority;
79 final SecurityManager securityManager = System.getSecurityManager();
80 this.group = securityManager != null ? securityManager.getThreadGroup()
81 : Thread.currentThread().getThreadGroup();
82 }
83
84 @Override
85 public Thread newThread(final Runnable runnable) {
86 // Log4jThread prefixes names with "Log4j2-".
87 final Thread thread = new Log4jThread(group, runnable, threadNamePrefix + THREAD_NUMBER.getAndIncrement(), 0);
88 if (thread.isDaemon() != daemon) {
89 thread.setDaemon(daemon);
90 }
91 if (thread.getPriority() != priority) {
92 thread.setPriority(priority);
93 }
94 return thread;
95 }
96
97 }