001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *     http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.configuration2.sync;
018
019/**
020 * <p>
021 * An implementation of the {@code Synchronizer} interface which does not perform any synchronization.
022 * </p>
023 * <p>
024 * This class is the option of choice for applications that do not access configuration concurrently. All methods
025 * required by the {@code Synchronizer} interface are just empty dummies. Therefore, this class does not have any
026 * synchronization overhead. Of course, configurations using this {@code Synchronizer} implementation are not
027 * thread-safe!
028 * </p>
029 * <p>
030 * Implementation note: This class is an enumeration because only a single instance needs to exist. This instance can be
031 * shared between arbitrary configurations.
032 * </p>
033 *
034 * @since 2.0
035 */
036public enum NoOpSynchronizer implements Synchronizer {
037    /** The single shared instance of this class. */
038    INSTANCE;
039
040    @Override
041    public void beginRead() {
042        // empty
043    }
044
045    @Override
046    public void beginWrite() {
047        // empty
048    }
049
050    @Override
051    public void endRead() {
052        // empty
053    }
054
055    @Override
056    public void endWrite() {
057        // empty
058    }
059}