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 * https://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 package org.apache.commons.configuration2.sync;
18
19 /**
20 * <p>
21 * An enumeration used by {@link SynchronizerSupport} to specify how an object is locked.
22 * </p>
23 * <p>
24 * The {@code SynchronizerSupport} interface allows locking an object. This can be done in different ways controlling
25 * the level of concurrency still possible with the object. One of the constants defined here can be passed in when
26 * calling the {@code lock()} method of a {@code SynchronizerSupport} object. (Note that at the end of the day it is up
27 * to a concrete implementation of {@link Synchronizer} how these lock modes are interpreted.)
28 * </p>
29 *
30 * @since 2.0
31 */
32 public enum LockMode {
33 /**
34 * Lock mode <em>READ</em>. The object is accessed in a read-only manner. Typically, this means that other read locks
35 * can be granted while concurrent writes are not permitted.
36 */
37 READ,
38
39 /**
40 * Lock mode <em>WRITE</em>. The object is updated. This usually means that this object is exclusively locked. Attempts
41 * of other readers or writers will block until the current update operation is complete.
42 */
43 WRITE
44 }