    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
    038    /** The single shared instance of this class. */
    039    INSTANCE;
    040
    041    @Override
    042    public void beginRead() {
    043        // empty
    044    }
    045
    046    @Override
    047    public void beginWrite() {
    048        // empty
    049    }
    050
    051    @Override
    052    public void endRead() {
    053        // empty
    054    }
    055
    056    @Override
    057    public void endWrite() {
    058        // empty
    059    }
    060}