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A fast dependency injector for Android and Java.

There is a newer version: 2.52

/*
 * Copyright (C) 2014 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.producers;

import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import dagger.internal.Beta;
import dagger.producers.internal.CancellableProducer;
import dagger.producers.internal.CancellationListener;

/** Utility methods to create {@link Producer}s. */
@Beta
public final class Producers {
  /** Returns a producer that succeeds with the given value. */
  public static  Producer immediateProducer(final T value) {
    return new ImmediateProducer<>(Futures.immediateFuture(value));
  }

  /** Returns a producer that fails with the given exception. */
  public static  Producer immediateFailedProducer(final Throwable throwable) {
    return new ImmediateProducer<>(Futures.immediateFailedFuture(throwable));
  }

  /** A {@link CancellableProducer} with an immediate result. */
  private static final class ImmediateProducer implements CancellableProducer {
    private final ListenableFuture future;

    ImmediateProducer(ListenableFuture future) {
      this.future = future;
    }

    @Override
    public ListenableFuture get() {
      return future;
    }

    @Override
    public void cancel(boolean mayInterruptIfRunning) {}

    @Override
    public Producer newDependencyView() {
      return this;
    }

    @Override
    public Producer newEntryPointView(CancellationListener cancellationListener) {
      return this;
    }
  }

  private Producers() {}
}