/* * Copyright (C) 2007 The Dagger Authors. * * 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 dagger; import static java.lang.annotation.ElementType.METHOD; import static java.lang.annotation.RetentionPolicy.RUNTIME; import java.lang.annotation.Documented; import java.lang.annotation.Retention; import java.lang.annotation.Target; /** * Annotates methods of a {@linkplain Module module} to create a provider method binding. The * method's return type is bound to its returned value. The {@linkplain Component component} * implementation will pass dependencies to the method as parameters. * *

Nullability

* *

Dagger forbids injecting {@code null} by default. Component implementations that invoke * {@code @Provides} methods that return {@code null} will throw a {@link NullPointerException} * immediately thereafter. {@code @Provides} methods may opt into allowing {@code null} by * annotating the method with any {@code @Nullable} annotation like * {@code javax.annotation.Nullable} or {@code androidx.annotation.Nullable}. * *

If a {@code @Provides} method is marked {@code @Nullable}, Dagger will only * allow injection into sites that are marked {@code @Nullable} as well. A component that * attempts to pair a {@code @Nullable} provision with a non-{@code @Nullable} injection site * will fail to compile. */ @Documented @Target(METHOD) @Retention(RUNTIME) public @interface Provides { }