MultiFormatWrapper.java

/**
*    Copyright (c) 2011-2014, OpenIoT
*   
*    This file is part of OpenIoT.
*
*    OpenIoT is free software: you can redistribute it and/or modify
*    it under the terms of the GNU Lesser General Public License as published by
*    the Free Software Foundation, version 3 of the License.
*
*    OpenIoT 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 Lesser General Public License for more details.
*
*    You should have received a copy of the GNU Lesser General Public License
*    along with OpenIoT.  If not, see <http://www.gnu.org/licenses/>.
*
*     Contact: OpenIoT mailto: info@openiot.eu
 * @author sp3dy
 * @author Ali Salehi
 * @author Mehdi Riahi
*/

package org.openiot.gsn.wrappers;

import org.openiot.gsn.beans.AddressBean;
import org.openiot.gsn.beans.DataField;

import java.io.Serializable;

import org.apache.log4j.Logger;

/**
 * This wrapper presents a MultiFormat protocol in which the data comes from the
 * system clock. Think about a sensor network which produces packets with
 * several different formats. In this example we have 3 different packets
 * produced by three different types of sensors. Here are the packet structures
 * : [temperature:double] , [light:double] , [temperature:double, light:double]
 * The first packet is for sensors which can only measure temperature while the
 * latter is for the sensors equipped with both temperature and light sensors.
 * 
 */
public class MultiFormatWrapper extends AbstractWrapper {
  private DataField[] collection = new DataField[] { new DataField("packet_type", "int", "packet type"),
      new DataField("temperature", "double", "Presents the temperature sensor."), new DataField("light", "double", "Presents the light sensor.") };
  private final transient Logger logger = Logger.getLogger(MultiFormatWrapper.class);
  private int counter;
  private AddressBean params;
  private long rate = 1000;

  public boolean initialize() {
    setName("MultiFormatWrapper" + counter++);
    
    params = getActiveAddressBean();
    
    if ( params.getPredicateValue( "rate" ) != null ) {
      rate = (long) Integer.parseInt( params.getPredicateValue( "rate"));
      
      logger.info("Sampling rate set to " + params.getPredicateValue( "rate") + " msec.");
    }
    
    return true;
  }

  public void run() {
    Double light = 0.0, temperature = 0.0;
    int packetType = 0;
    
    while (isActive()) {
      try {
        // delay 
        Thread.sleep(rate);
      } catch (InterruptedException e) {
        logger.error(e.getMessage(), e);
      }
      
      // create some random readings
      light = ((int) (Math.random() * 10000)) / 10.0;
      temperature = ((int) (Math.random() * 1000)) / 10.0;
      packetType = 2;

      // post the data to GSN
      postStreamElement(new Serializable[] { packetType, temperature, light });       
    }
  }

  public DataField[] getOutputFormat() {
    return collection;
  }

  public String getWrapperName() {
    return "MultiFormat Sample Wrapper";
  }  

  public void dispose() {
    counter--;
  }
}