Source code

001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.reef.vortex.api;
020
021import org.apache.reef.annotations.Unstable;
022import org.apache.reef.annotations.audience.ClientSide;
023import org.apache.reef.annotations.audience.Public;
024import org.apache.reef.util.Builder;
025import org.apache.reef.util.Optional;
026
027import java.io.Serializable;
028
029/**
030 * The policy for local aggregation on the {@link org.apache.reef.vortex.evaluator.VortexWorker}s.
031 * The Aggregation function will be triggered on the individual {@link VortexFunction} results on
032 * an "OR" basis of what is specified by the policy.
033 * TODO[REEF-504]: Clean up Serializable in Vortex.
034 */
035@ClientSide
036@Public
037@Unstable
038public final class VortexAggregatePolicy implements Serializable {
039  private final Optional<Integer> count;
040  private final int periodMilliseconds;
041
042  private VortexAggregatePolicy(final int periodMilliseconds, final Optional<Integer> count) {
043    this.periodMilliseconds = periodMilliseconds;
044    this.count = count;
045  }
046
047  /**
048   * @return the aggregation period in milliseconds.
049   */
050  public int getPeriodMilliseconds() {
051    return periodMilliseconds;
052  }
053
054  /**
055   * @return the count trigger for the aggregation.
056   */
057  public Optional<Integer> getCount() {
058    return count;
059  }
060
061  /**
062   * @return a new {@link Builder} for {@link VortexAggregatePolicy}.
063   */
064  public static AggregatePolicyBuilder newBuilder() {
065    return new AggregatePolicyBuilder();
066  }
067
068  /**
069   * A Builder class for {@link VortexAggregatePolicy}.
070   */
071  public static final class AggregatePolicyBuilder implements Builder<VortexAggregatePolicy> {
072    private Integer periodMilliseconds = null;
073    private Optional<Integer> count = Optional.empty();
074
075    private AggregatePolicyBuilder() {
076    }
077
078    /**
079     * Sets the period to trigger aggregation in milliseconds. Required parameter to build.
080     */
081    public AggregatePolicyBuilder setTimerPeriodTrigger(final int pOffsetMilliseconds) {
082      periodMilliseconds = pOffsetMilliseconds;
083      return this;
084    }
085
086    /**
087     * Sets the count trigger for aggregation. Not required.
088     */
089    public AggregatePolicyBuilder setCountTrigger(final int pCount) {
090      count = Optional.of(pCount);
091      return this;
092    }
093
094    /**
095     * Builds and returns a new {@link VortexAggregatePolicy} based on user's specification.
096     * The timer period is a required parameter for this to succeed.
097     * @throws IllegalArgumentException if required parameters are not set or if parameters are invalid.
098     */
099    @Override
100    public VortexAggregatePolicy build() throws IllegalArgumentException {
101      if (periodMilliseconds == null) {
102        throw new IllegalArgumentException("The aggregate period must be set.");
103      }
104
105      if (count.isPresent() && count.get() <= 0) {
106        throw new IllegalArgumentException("The count trigger must be greater than zero.");
107      }
108
109      return new VortexAggregatePolicy(periodMilliseconds, count);
110    }
111  }
112}