1 package org.apache.onami.scopes;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import com.google.inject.ScopeAnnotation;
23
24 import java.lang.annotation.ElementType;
25 import java.lang.annotation.Retention;
26 import java.lang.annotation.RetentionPolicy;
27 import java.lang.annotation.Target;
28
29 /**
30 * Same as {@link LazySingleton} with the addition of allowing for more
31 * concurrency. The various {@code com.google.inject.Scopes#SINGLETON} based scopes have
32 * a major concurrency restriction due to a blunt synchronization (see
33 * the comment inside of the Guice code). This version synchronizes
34 * on the object key and, thus, can construct multiple types of singletons
35 * concurrently.
36 */
37 @Target( { ElementType.TYPE, ElementType.METHOD } )
38 @Retention( RetentionPolicy.RUNTIME )
39 @ScopeAnnotation
40 public @interface ConcurrentLazySingleton
41 {
42 }