1 /**
2 * Licensed to jclouds, Inc. (jclouds) under one or more
3 * contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. jclouds licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.jclouds.rest.annotations;
20
21 import static java.lang.annotation.ElementType.ANNOTATION_TYPE;
22 import static java.lang.annotation.ElementType.FIELD;
23 import static java.lang.annotation.ElementType.METHOD;
24 import static java.lang.annotation.ElementType.PARAMETER;
25 import static java.lang.annotation.RetentionPolicy.RUNTIME;
26
27 import java.lang.annotation.Retention;
28 import java.lang.annotation.Target;
29
30 import javax.inject.Qualifier;
31
32 /**
33 * Extracts the only element of a collection or null
34 *
35 * @author Adrian Cole
36 * @see SelectJson
37 */
38 @Target( { ANNOTATION_TYPE, METHOD, FIELD, PARAMETER })
39 @Retention(RUNTIME)
40 @Qualifier
41 public @interface OnlyElement {
42
43 }