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Annotation and runtime support to generate Mongodb repositories. Mongo java driver, Gson, Jackson, Bson4jackson and Guava are required runtime dependencies, which included as transitive dependencies.
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/*
   Copyright 2013-2015 Immutables Authors and Contributors

   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 org.immutables.mongo.concurrent;

import com.google.common.base.Function;
import com.google.common.util.concurrent.AsyncFunction;
import com.google.common.util.concurrent.ForwardingListenableFuture.SimpleForwardingListenableFuture;
import com.google.common.util.concurrent.FutureCallback;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.MoreExecutors;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import static com.google.common.base.Preconditions.checkNotNull;

/**
 * Provides default wrapping implementation of {@link FluentFuture}
 */
public final class FluentFutures {
  private FluentFutures() {}

  private static class WrapingFluentFuture
      extends SimpleForwardingListenableFuture
      implements FluentFuture {

    private final Executor executor;

    private WrapingFluentFuture(ListenableFuture future, Executor executor) {
      super(future);
      this.executor = checkNotNull(executor);
    }

    @Override
    public V getUnchecked() {
      return Futures.getUnchecked(this);
    }

    @Override
    public FluentFuture addCallback(FutureCallback callback) {
      Futures.addCallback(this, callback, executor);
      return this;
    }

    @Override
    public FluentFuture catching(Function fallback) {
      return from(Futures.catching(this, Throwable.class, fallback, executor));
    }

    @Override
    public FluentFuture withFallbackValue(final V value) {
      return catching(new Function() {
        @Override
        public V apply(Throwable t) {
          return value;
        }
      });
    }

    @Override
    public  FluentFuture transform(Function function) {
      return from(Futures.transform(this, function, executor));
    }

    @Override
    public  FluentFuture asyncTransform(AsyncFunction function) {
      return from(Futures.transformAsync(this, function, executor));
    }

    @Override
    public FluentFuture withExecutor(Executor executor) {
      if (this.executor == executor) {
        return this;
      }
      return new WrapingFluentFuture<>(delegate(), executor);
    }

    @Override
    public  FluentFuture lazyTransform(Function function) {
      return new LazyTransformedFluentFuture<>(this, function, executor);
    }
  }

  private static class LazyTransformedFluentFuture extends WrapingFluentFuture {
    private final Function function;
    private final ListenableFuture fromFuture;

    // Any get operation will go through transform function
    @SuppressWarnings("unchecked")
    LazyTransformedFluentFuture(
        ListenableFuture fromFuture,
        Function function,
        Executor executor) {
      super((ListenableFuture) fromFuture, executor);
      this.fromFuture = fromFuture;
      this.function = function;
    }

    @Override
    public V get() throws InterruptedException, ExecutionException {
      return function.apply(fromFuture.get());
    }

    @Override
    public V get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException {
      return function.apply(fromFuture.get(timeout, unit));
    }
  }

  /**
   * Unnecessary conversion, already have a fluent future. This method exists solely to detect
   * unnecessary conversion from a {@link FluentFuture}.
   * @deprecated you don't need to convert to a fluent future, it is already is
   * @param  value type
   * @param future future
   * @return same instance
   */
  @Deprecated
  public static  FluentFuture from(FluentFuture future) {
    return future;
  }

  /**
   * Wraps listenable future with a fluent future.
   * @param  value type
   * @param future future
   * @return fluent instance
   */
  public static  FluentFuture from(ListenableFuture future) {
    if (future instanceof FluentFuture) {
      return (FluentFuture) future;
    }
    return new WrapingFluentFuture<>(future, MoreExecutors.directExecutor());
  }
}