| /////////////////////////////////////////////////////////////// |
| * 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. |
| /////////////////////////////////////////////////////////////// |
| |
| [[library-locking, Locking Library]] |
| = Locking = |
| |
| [devstatus] |
| -------------- |
| source=libraries/locking/dev-status.xml |
| -------------- |
| |
| The Locking Library is a simple way to mark method with Read or Write locks, and the details is handled by this |
| library. |
| |
| This library is heavily used in EntityStore implementations. |
| |
| |
| include::../../build/docs/buildinfo/artifact.txt[] |
| |
| The library creates a +java.util.concurrent.ReentrantReadWriteLock+ which is shared for all methods within the |
| composite. It then acquires the read or write lock in a concern that is applied to the methods of the composite, which |
| have the corresponding annotations. |
| |
| == +@ReadLock+ == |
| This annotation will apply the +ReadLockConcern+ to the method, and acquire the +lock.readLock()+ on entry and relase |
| it on exit of the method. See the +ReentrantReadWriteLock+ for details on how/when to use it and the exact semantics. |
| |
| == +@WriteLock+ == |
| This annotation will apply the +WriteLockConcern+ to the method, and acquire the +lock.writeLock()+ on entry and relase |
| it on exit of the method. See the +ReentrantReadWriteLock+ for details on how/when to use it and the exact semantics. |
| |
| == +LockingAbstractComposite+ == |
| This composite type is the easiest way to use this library. Simple extend you composite type interface with this |
| interface and start marking the methods with the above annotations. No other complex assembly is required. |
| |
| [source,java] |
| ---- |
| public interface SomeService |
| extends ServiceComposite, LockingAbstractComposite |
| { |
| } |
| ---- |
| |
| or apply it during assembly, in case that is the only choice (such as existing/external interfaces) |
| |
| [snippet,java] |
| ---- |
| source=libraries/locking/src/test/java/org/qi4j/library/locking/DocumentationSupport.java |
| tag=assembly |
| ---- |
| |