package username.analysis;

/**
 * A class that assists in the analysis of methods.
 *
 * @author Samuel A. Rebelsky
 * @version 1.0 of April 2006
 */
public class Analyst
{

  // +--------+--------------------------------------------------
  // | Fields |
  // +--------+

  /** A counter for the number of steps an algorithm takes. */
  long steps;

  /** The time the algorithm started. */
  long start;

  /** The time the algorithm started. */
  long finish;


  // +--------------+--------------------------------------------
  // | Constructors |
  // +--------------+

  /**
   * Prepare to analyze an algorithm.
   */
  public Analyst()
  {
    this.reset();
  } // Analyst()
  
  
  // +---------------------+-------------------------------------
  // | Bookkeeping Methods |
  // +---------------------+

  /**
   * Reset the count of the number of steps spent.
   */
  public void reset()
  {
    this.steps = 0;
    this.start = System.currentTimeMillis();
    this.finish = 0;
  } // reset()

  /**
   * Count one step.
   */
  public void step()
  {
    ++this.steps;
  } // step()

  /**
   * Get the total number of steps used.
   */
  public long steps() 
  {
    return this.steps;
  } // steps()

  /**
   * Get the elapsed time.
   */
  public long elapsed()
  {
    if (this.finish == 0) {
      return System.currentTimeMillis() - this.start;
    }
    else {
      return this.finish - this.start;
    }
  } // elapsed()

  /**
   * Stop counting time.
   */
  public void stop() 
  {
    this.finish = System.currentTimeMillis();
  } // stop()
} // class Analyst