euclideannetwork.java

pastry的java实现的2.0b版

/*************************************************************************

"FreePastry" Peer-to-Peer Application Development Substrate 

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********************************************************************************/
package rice.pastry.direct;
import java.lang.*;

import java.util.*;

import rice.environment.Environment;
import rice.environment.logging.Logger;
import rice.environment.random.RandomSource;
import rice.pastry.*;
import rice.pastry.messaging.*;

/**
 * Euclidean network topology and idealized node life. Emulates a network of
 * nodes that are randomly placed in a plane. Proximity is based on euclidean
 * distance in the plane.
 *
 * @version $Id: EuclideanNetwork.java 2919 2006-01-16 12:54:15Z jeffh $
 * @author Andrew Ladd
 * @author Rongmei Zhang
 */
public class EuclideanNetwork extends BasicNetworkSimulator {

  /**
   * Constructor.
   *
   * @param env DESCRIBE THE PARAMETER
   */
  public EuclideanNetwork(Environment env) {
    super(env);
  }

  /**
   * DESCRIBE THE METHOD
   *
   * @return DESCRIBE THE RETURN VALUE
   */
  public NodeRecord generateNodeRecord() {
    return new EuclideanNodeRecord();
  }

  /**
   * Initialize a random Euclidean NodeRecord
   *
   * @version $Id: EuclideanNetwork.java 2919 2006-01-16 12:54:15Z jeffh $
   * @author amislove
   */
  private class EuclideanNodeRecord implements NodeRecord {
    /**
     * The euclidean position.
     */
    public int x, y;

    /**
     * DESCRIBE THE FIELD
     */
    public boolean alive;

    /**
     * Constructor for NodeRecord.
     *
     */
    public EuclideanNodeRecord() {
      x = random.nextInt() % 10000;
      y = random.nextInt() % 10000;

      alive = true;
    }


    /**
     * DESCRIBE THE METHOD
     *
     * @param that DESCRIBE THE PARAMETER
     * @return DESCRIBE THE RETURN VALUE
     */
    public int proximity(NodeRecord that) {
      EuclideanNodeRecord nr = (EuclideanNodeRecord) that;
      int dx = x - nr.x;
      int dy = y - nr.y;

      return ((int) Math.sqrt(dx * dx + dy * dy));
    }
  }
}