signal.java

用java写的jt-jpeg。jt表示java time package

/*
 |
 | Signal.java
 |
 | Signal class
 | James Shin Young
 |
 | Created:  December 12, 1997
 |
 | Copyright (c) 1997 by James Shin Young and the Regents
 | of the University of California.  All rights reserved.
 |
 | Permission to use, copy, modify, and distribute this software
 | and its documentation for NON-COMMERCIAL purposes and without
 | fee is hereby granted provided that this copyright notice
 | appears in all copies.
 |
 */

package jcp;
import java.util.Vector;

/**
 *  Instances of Signal serve as the containers for the data values that
 *  are sent between components. They are Immutable, meaning that their
 *  contents may not be altered after they are created. They must be
 *  extended in order to actually store data.
 *
 * @author James Shin Young
 * @see Component
 * @see Port
 */


public class Signal
{
    /**
     *  UNDEFINED is a special signal representing an undefined value.
     *  Ports should be assigned this instead of null when no value
     *  is defined for it. Components may test ports' values for equality
     *  using ==. (This is a good thing)
     */
    public final static Signal UNDEFINED = new Signal("undefined");

    /**
     *  TRUE is a special signal representing the true boolean value.
     */
    public final static Signal TRUE = new Signal("true");

    /**
     *  FALSE is a special signal representing the false boolean value.
     */
    public final static Signal FALSE = new Signal("false");

    // Holds the string representation of this signal
    private String name;

    // Constructors
    public Signal(String name) {
        if (name != null) {
            this.name = name;
        } else {
            this.name = super.toString();
        }
    }

    public Signal() {
        this((String)null);
    }

    public String toString() {
        return name;
    }

}