hamr.core.general.counter.DertaCounter.java Source code

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Here is the source code for hamr.core.general.counter.DertaCounter.java

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/*
  Copyright (c) 2015, Yiju Wei. 
    
  HAMR is a Frame let you use annotations to describe and execute a MapReduce process.
    
  This program is free software; you can redistribute it and/or modify it under the terms
  of the GNU General Public License as published by the Free Software Foundation; version 2
  of the License.
    
  This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
  without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  See the GNU General Public License for more details.
    
  You should have received a copy of the GNU General Public License along with this
  program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth
  Floor, Boston, MA 02110-1301  USA
    
 */
package hamr.core.general.counter;

import java.lang.reflect.Field;
import java.util.HashMap;
import java.util.Map;

import org.apache.hadoop.mapreduce.Reducer.Context;

import hamr.core.general.annotations.ReduceField;
import hamr.core.general.annotations.TargetField;
import hamr.core.general.bean.AnnotedBean;

public class DertaCounter extends Counter {

    private Map<String, Long> firstData;
    private Map<String, Long> lastData;
    static Map<Field, ReduceField> countingFields;
    static Map<Field, TargetField> targetFields;

    public DertaCounter(@SuppressWarnings("rawtypes") Context context) {
        super(context);
        firstData = new HashMap<String, Long>();
        lastData = new HashMap<String, Long>();
    }

    public void count(AnnotedBean ab) {
        if (countingFields == null) {
            countingFields = getCountFields(ab);
            for (Field f : countingFields.keySet()) {
                try {
                    firstData.put(f.getName(), f.getLong(ab));
                } catch (IllegalArgumentException | IllegalAccessException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }
        for (Field f : countingFields.keySet()) {
            try {
                lastData.put(f.getName(), f.getLong(ab));
            } catch (IllegalArgumentException | IllegalAccessException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }

    public boolean end(AnnotedBean ret) {
        if (ret == null) {
            return false;
        }
        if (targetFields == null) {
            targetFields = getTargetFields(ret);
        }
        for (Field f : targetFields.keySet()) {
            String fromField = targetFields.get(f).fromField();
            Long derta = lastData.get(fromField) - firstData.get(firstData);
            try {
                f.set(ret, derta);
            } catch (IllegalArgumentException | IllegalAccessException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        return true;
    }

}