org.cloudata.util.matrix.MatrixMutiplyMap.java Source code

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Here is the source code for org.cloudata.util.matrix.MatrixMutiplyMap.java

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/**
 * 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.cloudata.util.matrix;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reporter;
import org.apache.log4j.Logger;
import org.cloudata.core.common.conf.CloudataConf;

public class MatrixMutiplyMap implements Mapper<WritableComparable, Writable, MatrixItem, Text> {
    static final Logger LOG = Logger.getLogger(MatrixMutiplyMap.class.getName());
    //Column -> result
    HashMap<String, Double> calResult = new HashMap<String, Double>();
    String previousRow;
    int count = 1;
    AbstractMatrix targetMatrix;
    long startTime = System.currentTimeMillis();
    IOException err;
    OutputCollector collector;

    public void map(WritableComparable key, Writable value, OutputCollector<MatrixItem, Text> collector,
            Reporter reporter) throws IOException {
        if (err != null) {
            throw err;
        }

        if (this.collector == null) {
            this.collector = collector;
        }

        MatrixItem matrixItem = (MatrixItem) value;
        String row = matrixItem.row;
        String column = matrixItem.column;

        // ? row  ?? ? ? .
        if (previousRow != null && !previousRow.equals(row)) {
            for (Map.Entry<String, Double> entry : calResult.entrySet()) {
                String targetCol = entry.getKey();
                Double resultValue = entry.getValue();

                MatrixItem resultItem = new MatrixItem();
                resultItem.row = previousRow;
                resultItem.column = targetCol;
                collector.collect(resultItem, new Text(resultValue.toString()));
            }
            // 
            calResult = new HashMap<String, Double>();

            if (count % 100 == 0) {
                LOG.info(count + " rows completed: " + (System.currentTimeMillis() - startTime) + " ms, last row="
                        + previousRow);
                startTime = System.currentTimeMillis();
            }

            count++;
        }
        targetMatrix.initScannerForTarget(column);
        MatrixItem targetMatrixItem = null;
        try {
            while ((targetMatrixItem = targetMatrix.nextItemForTarget()) != null) {
                String targetCol = targetMatrixItem.column;
                double result = matrixItem.value * targetMatrixItem.value;

                if (calResult.containsKey(targetCol)) {
                    calResult.put(targetCol, calResult.get(targetCol) + result);
                } else {
                    calResult.put(targetCol, result);
                }
            }
        } finally {
            targetMatrix.closeScannerForTarget();
        }
        previousRow = row;
    }

    public void configure(JobConf job) {
        CloudataConf conf = new CloudataConf();
        boolean sparse = job.getBoolean(MatrixInputFormat.MATRIX_TARGET_SPARSE, false);
        String targetTableName = job.get(MatrixInputFormat.MATRIX_TARGET_TABLE);
        String targetColumnName = job.get(MatrixInputFormat.MATRIX_TARGET_COLUMN);

        try {
            if (sparse) {
                targetMatrix = new SparseMatrix(conf, targetTableName, targetColumnName);
            } else {
                targetMatrix = new Matrix(conf, targetTableName, targetColumnName);
            }
        } catch (IOException e) {
            err = e;
        }
    }

    public void close() throws IOException {
        //  row?  
        if (calResult != null && calResult.size() > 0) {
            for (Map.Entry<String, Double> entry : calResult.entrySet()) {
                String targetCol = entry.getKey();
                Double resultValue = entry.getValue();

                MatrixItem resultItem = new MatrixItem();
                resultItem.row = previousRow;
                resultItem.column = targetCol;
                //collector.collect(resultItem, new Text(resultValue.toString()));
            }
        }
    }
}