constraint.java

使用java编写的关于通讯及串口编程所必需的类库

/*
 * Constraint.java
 *
 * This is a required part of the com.adaptiveview.ospso package.
 *
 * Copyright (C) 2003 AdaptiveView.com
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 * 
 * This library 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
 * General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 * 
 * You may contact AdaptiveView.com via email at: [e-mail] 
 *
 */

package com.adaptiveview.ospso;

/**A Constraint is simply the limits to (the minimum and maximum of) a number range.
 * Some constraints have special boundary (limit) types that indicate how a value that
 * exceeds the boundaries is to be modified such that it is again within the boundaries.
 * There are three such types: 
 *<blockquote>
 *<B>STICK</B>: the value is set to the exceeded boundary's value
 * -- e.g., if the boundaries are 1 and 10 and the value is 12, it is set to 10,
 * <p><B>WRAP</B>: the value wraps around to the opposite boundary -- e.g., if the boundaries
 * are 1 and 10 and the value is 12, the value will be set to 2, and 
 *<p><B>BOUNCE</B> the value, in effect, bounces off the exceeded boundary and is 
 * applied in the opposite direction -- e.g., if the boundaries are 1 and 10 and the 
 * value is 12, the value will be set to 8.
 *</blockquote>
 *
 * @author  unknown
 */
public class Constraint implements com.adaptiveview.ospso.dmi.DMI_GPL_License {
    
    public static final byte NONE = 0;
    public static final byte WRAP = 125;
    public static final byte BOUNCE = 126;
    public static final byte STICK = 127;
    
    private double minimum;
    private double maximum;
    private byte boundaryType;
    
    /** Creates a new instance of Constraint */
    public Constraint(double minimum, double maximum, byte boundaryType) throws IllegalArgumentException {
        if (!(boundaryType == NONE || boundaryType == WRAP || boundaryType == BOUNCE || boundaryType == STICK))
            throw new IllegalArgumentException("Invalid boundary type.");
        if (boundaryType == NONE) {
          if (minimum > maximum)
              throw new IllegalArgumentException("Maximum must be greater than minimum for specified boundary type.");
        }
        else
        if (minimum >= maximum)
            throw new IllegalArgumentException("Maximum must be greater than minimum for specified boundary type.");
        this.minimum = minimum;
        this.maximum = maximum;
        this.boundaryType = boundaryType;
    }
    
    /** Creates a new instance of Constraint with no boundary type */
    public Constraint(double minimum, double maximum) throws IllegalArgumentException {
        this(minimum,maximum,NONE);
    }
    
    public double getMinimum() {
        return this.minimum;
    }
    
    public double getMaximum() {
        return this.maximum;
    }
    
    public byte getBoundaryType() {
        return this.boundaryType;
    }
    
}