1 /**
2 * Copyright 2008 Atlassian Pty Ltd
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 package com.atlassian.util.concurrent;
18
19 import java.util.concurrent.Callable;
20 import java.util.concurrent.locks.ReadWriteLock;
21
22 /**
23 * {@link ManagedLock} allows {@link Callable callables}, {@link Runnable
24 * runnables} and {@link Supplier suppliers} to be run under a lock that is
25 * resolved against an input object.
26 *
27 * @since 0.0.7
28 */
29 public interface ManagedLock {
30 /**
31 * Execute the supplied {@link Callable} under a lock determined by the
32 * descriptor.
33 *
34 * @param <R> the result type
35 * @param callable the operation to perform under lock
36 * @return whatever the supplied {@link Callable} returns
37 * @throws Exception if the supplied {@link Callable} throws an exception
38 */
39 <R> R withLock(final @NotNull Callable<R> callable) throws Exception;
40
41 /**
42 * Execute the supplied {@link Supplier} under a lock determined by the
43 * descriptor.
44 * <p>
45 * Unlike {@link #withLock(Callable)} this version returns a result and does
46 * not declare a checked exception.
47 *
48 * @param <R> the result type
49 * @param supplier the operation to perform under lock
50 * @return whatever the supplied {@link Callable} returns
51 */
52 <R> R withLock(final @NotNull Supplier<R> supplier);
53
54 /**
55 * Execute the supplied {@link Runnable} under a lock determined by the
56 * descriptor.
57 *
58 * @param runnable the operation to perform under lock
59 */
60 void withLock(final @NotNull Runnable runnable);
61
62 /**
63 * Maintains two managed locks that internally use the same
64 * {@link ReadWriteLock read/write locks}
65 */
66 interface ReadWrite {
67 /**
68 * For performing operations that require read locks
69 *
70 * @return a lock manager that uses read locks
71 */
72 ManagedLock read();
73
74 /**
75 * For performing operations that require write locks
76 *
77 * @return a lock manager that uses write locks
78 */
79 ManagedLock write();
80 }
81 }