ComputeContentEvent.java

package com.yahoo.labs.samoa.learners.classifiers.trees;

/*
 * #%L
 * SAMOA
 * %%
 * Copyright (C) 2013 Yahoo! Inc.
 * %%
 * 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.
 * #L%
 */

import com.esotericsoftware.kryo.Kryo;
import com.esotericsoftware.kryo.Serializer;
import com.esotericsoftware.kryo.io.Input;
import com.esotericsoftware.kryo.io.Output;

/**
 * Compute content event is the message that is sent by Model Aggregator Processor
 * to request Local Statistic PI to start the local statistic calculation for splitting
 * @author Arinto Murdopo
 *
 */
public final class ComputeContentEvent extends ControlContentEvent {
    
	private static final long serialVersionUID = 5590798490073395190L;
	
	private final double[] preSplitDist;
	private final long splitId;
	
	public ComputeContentEvent(){
		super(-1);
		preSplitDist = null;
		splitId = -1;
	}

	ComputeContentEvent(long splitId, long id, double[] preSplitDist) {
		super(id);
		//this.preSplitDist = Arrays.copyOf(preSplitDist, preSplitDist.length);
		this.preSplitDist = preSplitDist;
		this.splitId = splitId;
	}

	@Override
	LocStatControl getType() {
		return LocStatControl.COMPUTE;
	}
	
	double[] getPreSplitDist(){
		return this.preSplitDist;
	}
	
	long getSplitId(){
		return this.splitId;
	}
	
	/**
	 * The Kryo serializer class for ComputeContentEevent when executing on top of Storm. 
	 * This class allow us to change the precision of the statistics.
	 * @author Arinto Murdopo
	 *
	 */
	public static final class ComputeCESerializer extends Serializer<ComputeContentEvent>{

		private static double PRECISION = 1000000.0;
		
		@Override
		public void write(Kryo kryo, Output output, ComputeContentEvent object) {
			output.writeLong(object.splitId, true);
			output.writeLong(object.learningNodeId, true);
			
			output.writeInt(object.preSplitDist.length, true);
			for(int i = 0; i < object.preSplitDist.length; i++){
				output.writeDouble(object.preSplitDist[i], PRECISION, true);
			}
		}

		@Override
		public ComputeContentEvent read(Kryo kryo, Input input,
				Class<ComputeContentEvent> type) {
			long splitId = input.readLong(true);
			long learningNodeId = input.readLong(true);
			
			int dataLength = input.readInt(true);
			double[] preSplitDist = new double[dataLength];
			
			for(int i = 0; i < dataLength; i++){
				preSplitDist[i] = input.readDouble(PRECISION, true);
			}
			
			return new ComputeContentEvent(splitId, learningNodeId, preSplitDist);
		}
	}
	
	/**
	 * The Kryo serializer class for ComputeContentEevent when executing on top of Storm 
	 * with full precision of the statistics.
	 * @author Arinto Murdopo
	 *
	 */
	public static final class ComputeCEFullPrecSerializer extends Serializer<ComputeContentEvent>{

		@Override
		public void write(Kryo kryo, Output output, ComputeContentEvent object) {
			output.writeLong(object.splitId, true);
			output.writeLong(object.learningNodeId, true);
			
			output.writeInt(object.preSplitDist.length, true);
			for(int i = 0; i < object.preSplitDist.length; i++){
				output.writeDouble(object.preSplitDist[i]);
			}
		}

		@Override
		public ComputeContentEvent read(Kryo kryo, Input input,
				Class<ComputeContentEvent> type) {
			long splitId = input.readLong(true);
			long learningNodeId = input.readLong(true);
			
			int dataLength = input.readInt(true);
			double[] preSplitDist = new double[dataLength];
			
			for(int i = 0; i < dataLength; i++){
				preSplitDist[i] = input.readDouble();
			}
			
			return new ComputeContentEvent(splitId, learningNodeId, preSplitDist);
		}
		
	}

}