public @interface

Keep

implements java.lang.annotation.Annotation

 androidx.annotation.Keep

Gradle dependencies

compile group: 'androidx.annotation', name: 'annotation', version: '1.4.0-beta01'

  • groupId: androidx.annotation
  • artifactId: annotation
  • version: 1.4.0-beta01

Artifact androidx.annotation:annotation:1.4.0-beta01 it located at Google repository (https://maven.google.com/)

Androidx artifact mapping:

androidx.annotation:annotation com.android.support:support-annotations

Androidx class mapping:

androidx.annotation.Keep android.support.annotation.Keep

Overview

Denotes that the annotated element should not be removed when the code is minified at build time. This is typically used on methods and classes that are accessed only via reflection so a compiler may think that the code is unused.

Do not use this within library code. As a best practice, minification should be able to remove all library code for libraries that are added as dependencies but not used. For library code, consider instead using conditional keep rules. E.g.: -if ... -keep ...

Example:


  @Keep
  public void foo() {
      ...
  }
 

Summary

Source

/*
 * Copyright (C) 2015 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package androidx.annotation;

import static java.lang.annotation.ElementType.ANNOTATION_TYPE;
import static java.lang.annotation.ElementType.CONSTRUCTOR;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.PACKAGE;
import static java.lang.annotation.ElementType.TYPE;
import static java.lang.annotation.RetentionPolicy.CLASS;

import java.lang.annotation.Retention;
import java.lang.annotation.Target;

/**
 * Denotes that the annotated element should not be removed when
 * the code is minified at build time. This is typically used
 * on methods and classes that are accessed only via reflection
 * so a compiler may think that the code is unused.
 * <p>
 * Do not use this within library code. As a best practice,
 * minification should be able to remove all library code for
 * libraries that are added as dependencies but not used. For
 * library code, consider instead using conditional keep rules.
 * E.g.: -if ... -keep ...
 *
 * <p>
 * Example:
 * <pre><code>
 *  &#64;Keep
 *  public void foo() {
 *      ...
 *  }
 * </code></pre>
 */
@Retention(CLASS)
@Target({PACKAGE, TYPE, ANNOTATION_TYPE, CONSTRUCTOR, METHOD, FIELD})
public @interface Keep {
}