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 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 }