bytestatistics.java

本源码给出了在jbuilder下实现串口通信,并且如何使用

/*
 * @(#)ByteStatistics.java	1.1 98/06/02 SMI
 *
 * Author: Tom Corson
 *
 * Copyright (c) 1998 Sun Microsystems, Inc. All Rights Reserved.
 *
 * Sun grants you ("Licensee") a non-exclusive, royalty free, license
 * to use, modify and redistribute this software in source and binary
 * code form, provided that i) this copyright notice and license appear
 * on all copies of the software; and ii) Licensee does not utilize the
 * software in a manner which is disparaging to Sun.
 *
 * This software is provided "AS IS," without a warranty of any kind.
 * ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES,
 * INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN AND
 * ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY
 * LICENSEE AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THE
 * SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS
 * BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT,
 * INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES,
 * HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY, ARISING
 * OUT OF THE USE OF OR INABILITY TO USE SOFTWARE, EVEN IF SUN HAS BEEN
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 *
 * This software is not designed or intended for use in on-line control
 * of aircraft, air traffic, aircraft navigation or aircraft
 * communications; or in the design, construction, operation or
 * maintenance of any nuclear facility. Licensee represents and
 * warrants that it will not use or redistribute the Software for such
 * purposes.
 */

package samples.ParallelBlackBox;

import javax.comm.*;

import java.awt.*;

public class ByteStatistics
    extends Panel {
  private BufferSize buffer;
  private ByteCounter counter,
  rate;
  private long lastTime,
  lastBaudRate,
  lastCount;
  private int bitsPerCharacter;
  private boolean avgRate,
  inputBuffer;
  private ParallelPort port;

  public ByteStatistics(String text,
                        int size,
                        ParallelPort port,
                        boolean inputBuffer,
                        boolean average) {
    super();

    this.inputBuffer = inputBuffer;

    this.setLayout(new BorderLayout());

    counter = new ByteCounter(text, size);

    this.add("West", counter);

    rate = new ByteCounter("Baud Rate", 6);

    this.add("East", rate);

    buffer = new BufferSize(6, port, inputBuffer);

    this.add("Center", buffer);

    this.setBitsPerCharacter(10);

    this.setPort(port);

    this.lastTime = 0;

    this.lastCount = 0;

    this.lastBaudRate = 0;

    if (average) {
      this.avgRate = true;
    }

    else {
      this.avgRate = false;
    }
  }

  public ByteStatistics(String text,
                        int size,
                        ParallelPort port,
                        boolean inputBuffer) {
    this(text, size, port, inputBuffer, true);
  }

  public void setPort(ParallelPort port) {
    this.port = port;

    this.buffer.setPort(port);
  }

  public void setBitsPerCharacter(int val) {
    this.bitsPerCharacter = val;
  }

  public void showValues() {
    this.buffer.showValue();
  }

  public void clearValues() {
    this.buffer.setValue(0);

    this.counter.setValue(0);

    this.rate.setValue(0);
  }

  public long getValue() {
    return this.counter.getValue();
  }

  public void setValue(long val) {
    if (val == 0) {
      this.resetRate();
    }

    this.counter.setValue(val);

    this.setRate();
  }

  public void incrementValue(long val) {
    this.counter.incrementValue(val);

    this.setRate();
  }

  public void resetRate() {
    /*
      if (port != null)
      {
       if (inputBuffer)
       {
        System.out.println("Reseting receive baud rate for "
            + port.getName());
       }

       else
       {
        System.out.println("Reseting transmit baud rate for "
            + port.getName());
       }
      }
     */
    this.lastTime = 0;
    this.lastBaudRate = 0;
  }

  private void setRate() {
    long baudRate,
        time = System.currentTimeMillis(),
        val = this.counter.getValue();

    if ( (this.rate.getValue() == 0) && (this.lastBaudRate != 0)) {
      this.resetRate();
    }

    if ( (this.lastTime == 0) || (val == 0)
        || (val < this.lastCount)) {
      this.lastTime = time;
      this.lastCount = val;
    }

    else if (time > this.lastTime) {
      baudRate = ( (val - this.lastCount)
                  * this.bitsPerCharacter * 1000)
          / (time - this.lastTime);

//		System.out.println("((" + val + " - " + this.lastCount + ")"
//				   + " * " + this.bitsPerCharacter
//				   + " * 1000 ) / "
//				   + "(" + time + " - " + this.lastTime + ")");

      if (this.avgRate) {
        /*
         *  This is a silly hack to auto-reset
         *  the counter if the user stops transmitting
         */

        if (inputBuffer && (baudRate < 10)) {
          this.resetRate();
        }
      }

      else {
        this.lastCount = val;
        this.lastTime = time;
      }

      this.rate.setValue( (int) baudRate);
      this.lastBaudRate = baudRate;
    }
  }
}