lang/java/reef-common/src/main/java/org/apache/reef/runtime/common/driver/evaluator/IdlenessCallbackEventHandlerFactory.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.reef.runtime.common.driver.evaluator;

import org.apache.reef.annotations.audience.DriverSide;
import org.apache.reef.annotations.audience.Private;
import org.apache.reef.runtime.common.driver.idle.EventHandlerIdlenessSource;
import org.apache.reef.wake.EventHandler;

import javax.inject.Inject;

/**
 * Creates {@link IdlenessCallbackEventHandler}, which runs an idleness check after the innerHandler's
 * {@link EventHandler#onNext(Object)} call is handled.
 */
@Private
@DriverSide
final class IdlenessCallbackEventHandlerFactory {
  private final EventHandlerIdlenessSource idlenessSource;

  @Inject
  private IdlenessCallbackEventHandlerFactory(final EventHandlerIdlenessSource idlenessSource) {
    this.idlenessSource = idlenessSource;
  }

  /**
   * @return a new instance of {@link IdlenessCallbackEventHandler} wrapped with the specified innerHandler
   */
  <T> IdlenessCallbackEventHandler<T> createIdlenessCallbackWrapperHandler(
      final EventHandler<T> innerHandler) {
    return new IdlenessCallbackEventHandler<>(innerHandler, idlenessSource);
  }
}