| /* |
| * Written by Doug Lea with assistance from members of JCP JSR-166 |
| * Expert Group and released to the public domain, as explained at |
| * http://creativecommons.org/licenses/publicdomain |
| */ |
| |
| /** |
| * Interfaces and classes providing a framework for locking and waiting |
| * for conditions that is distinct from built-in synchronization and |
| * monitors. The framework permits much greater flexibility in the use of |
| * locks and conditions, at the expense of more awkward syntax. |
| * |
| * <p>The {@link java.util.concurrent.locks.Lock} interface supports |
| * locking disciplines that differ in semantics (reentrant, fair, etc), |
| * and that can be used in non-block-structured contexts including |
| * hand-over-hand and lock reordering algorithms. The main implementation |
| * is {@link java.util.concurrent.locks.ReentrantLock}. |
| * |
| * <p>The {@link java.util.concurrent.locks.ReadWriteLock} interface |
| * similarly defines locks that may be shared among readers but are |
| * exclusive to writers. Only a single implementation, {@link |
| * java.util.concurrent.locks.ReentrantReadWriteLock}, is provided, since |
| * it covers most standard usage contexts. But programmers may create |
| * their own implementations to cover nonstandard requirements. |
| * |
| * <p>The {@link java.util.concurrent.locks.Condition} interface |
| * describes condition variables that may be associated with Locks. |
| * These are similar in usage to the implicit monitors accessed using |
| * {@code Object.wait}, but offer extended capabilities. |
| * In particular, multiple {@code Condition} objects may be associated |
| * with a single {@code Lock}. To avoid compatibility issues, the |
| * names of {@code Condition} methods are different from the |
| * corresponding {@code Object} versions. |
| * |
| * <p>The {@link java.util.concurrent.locks.AbstractQueuedSynchronizer} |
| * class serves as a useful superclass for defining locks and other |
| * synchronizers that rely on queuing blocked threads. The {@link |
| * java.util.concurrent.locks.AbstractQueuedLongSynchronizer} class |
| * provides the same functionality but extends support to 64 bits of |
| * synchronization state. Both extend class {@link |
| * java.util.concurrent.locks.AbstractOwnableSynchronizer}, a simple |
| * class that helps record the thread currently holding exclusive |
| * synchronization. The {@link java.util.concurrent.locks.LockSupport} |
| * class provides lower-level blocking and unblocking support that is |
| * useful for those developers implementing their own customized lock |
| * classes. |
| * |
| * @since 1.5 |
| */ |
| package java.util.concurrent.locks; |