1 /*
2  * Copyright (C) 2017 The Android Open Source Project
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 package libcore.util;
17 
18 import static java.lang.annotation.ElementType.FIELD;
19 import static java.lang.annotation.ElementType.METHOD;
20 import static java.lang.annotation.ElementType.PARAMETER;
21 import static java.lang.annotation.ElementType.TYPE_USE;
22 import static java.lang.annotation.RetentionPolicy.SOURCE;
23 
24 import java.lang.annotation.Documented;
25 import java.lang.annotation.Retention;
26 import java.lang.annotation.Target;
27 
28 /**
29  * Denotes that a type use can be a null.
30  * <p>
31  * This is a marker annotation and it has no specific attributes.
32  * @hide
33  */
34 @Documented
35 @Retention(SOURCE)
36 @Target({FIELD, METHOD, PARAMETER, TYPE_USE})
37 @libcore.api.IntraCoreApi
38 public @interface Nullable {
39    /**
40     * Min Android API level (inclusive) to which this annotation is applied.
41     */
from()42    int from() default Integer.MIN_VALUE;
43 
44    /**
45     * Max Android API level to which this annotation is applied.
46     */
to()47    int to() default Integer.MAX_VALUE;
48 }
49