| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package com.twitter.distributedlog.lock; |
| |
| import com.twitter.distributedlog.exceptions.LockingException; |
| import com.twitter.util.Future; |
| |
| /** |
| * An implementation of {@link DistributedLock} which does nothing. |
| */ |
| public class NopDistributedLock implements DistributedLock { |
| |
| public static final DistributedLock INSTANCE = new NopDistributedLock(); |
| |
| private NopDistributedLock() {} |
| |
| @Override |
| public Future<? extends DistributedLock> asyncAcquire() { |
| return Future.value(this); |
| } |
| |
| @Override |
| public void checkOwnershipAndReacquire() throws LockingException { |
| // no-op |
| } |
| |
| @Override |
| public void checkOwnership() throws LockingException { |
| // no-op |
| } |
| |
| @Override |
| public Future<Void> asyncClose() { |
| return Future.Void(); |
| } |
| } |