leveldraw.java

无线网络管理

//
// NAME
//      $RCSfile: LevelDraw.java,v $
// DESCRIPTION
//      [given below in javadoc format]
// DELTA
//      $Revision: 1.3 $
// CREATED
//      $Date: 2006/01/17 17:43:54 $
// COPYRIGHT
//      Westhawk Ltd
// TO DO
//

/*
 * Copyright (C) 1996 - 2006 by Westhawk Ltd
 *
 * Permission to use, copy, modify, and distribute this software
 * for any purpose and without fee is hereby granted, provided
 * that the above copyright notices appear in all copies and that
 * both the copyright notice and this permission notice appear in
 * supporting documentation.
 * This software is provided "as is" without express or implied
 * warranty.
 * author <a href="mailto:[e-mail]">Tim Panton</a>
 */

package uk.co.westhawk.visual;

import java.lang.*;
import java.awt.*; 
import javax.swing.*;

/**
 * <p>
 * The LevelDraw class produces a lightweight component in the shape of
 * a Level. It can have a scale, and a label underneath.
 * </p>
 *
 * <p>
 * It is used by the getAllInterfacesUI application to visualize the speed.
 * </p>
 *
 * @see Level
 * @author <a href="mailto:[e-mail]">Birgit Arkesteijn</a>
 * @version $Revision: 1.3 $ $Date: 2006/01/17 17:43:54 $
 */
public class LevelDraw extends Canvas 
{
    private static final String     version_id =
        "@(#)$Id: LevelDraw.java,v 1.3 2006/01/17 17:43:54 birgit Exp $ Copyright Westhawk Ltd";

    private boolean doScale = false;
    private Color fg = Color.black;
    private Color bg = Color.lightGray;
    private Color lbg = Color.white;
    private Color lfg = Color.orange;

    private double value;
    private FontMetrics fm;
    private double dmax;

    private Image   image=null;
    private int     width, height;
    private boolean isChanged;

    final static String xaxis[] =
    {
        "0 B/s",
        "10 B/s",
        "100 B/s",
        "1 KB/s",
        "10 KB/s",
        "100 KB/s",
        "1 MB/s"
    };

    final static int    max = 1000000;
    final static int    min = 0;

    final static String max_str = "1 MB/s";
    final static String min_str = "0";

/**
 * Constructs a LevelDraw with no label
 */
public LevelDraw() 
{
    value = 0.0;
    dmax = Math.log(max) / Math.log(10);
    width = 0;
    height = 0;

    isChanged = true;
}


public void setValue(double v)
{
    if (v != value)
    {
        value = v;
        isChanged = true;
        repaint();
    }
}

public double getValue()
{
    return (value);
}

public void addNotify()
{
    super.addNotify();
    Font f = this.getFont();
    fm = this.getFontMetrics(f);
}

public void setScale(boolean b)
{
    if (b != doScale)
    {
        doScale = b;
        isChanged = true;
        repaint();
    }
}

public void setForeground(Color c)
{
    if (c != fg)
    {
        fg = c;
        isChanged = true;
        repaint();
    }
}

public void setBackground(Color c)
{
    if (c != bg)
    {
        bg = c;
        isChanged = true;
        repaint();
    }
}

public void setLevelBackground(Color c)
{
    if (c != lbg)
    {
        lbg = c;
        isChanged = true;
        repaint();
    }
}

public void setLevelForeground(Color c)
{
    if (c != lfg)
    {
        lfg = c;
        isChanged = true;
        repaint();
    }
}

/**
 * Paints the LevelDraw
 */
public void paint(Graphics g) 
{
    if (g != null)
    {
        int w = getSize().width-1;
        int h = getSize().height-1;

        if (w > 0 && h > 0)
        {
            if (image == null
                  ||
                width != w
                  ||
                height != h
                  ||
                isChanged)
            {
                width = w;
                height = h;

                image = createImage(width, height);
                drawImage(image, width, height);
            }
            g.drawImage(image, 0, 0, null);
        }
    }
}

public void update(Graphics g) 
{
    paint(g);
}

private void drawImage(Image image, int w, int h)
{
    Graphics g = image.getGraphics();

    // clear the whole image
    g.setColor(bg);
    g.fillRect(0, 0, w, h);

    int fonth = fm.getHeight();
    int scale = (int) ((h-2*fonth)/dmax);

    // the 4 corners of the Level:
    // to the left will be the labels of the xaxis
    // in the middle the value
    int xl;
    if (doScale)
    {
        xl = w/2-w/8;
    }
    else
    {
        xl = w/8;
    }
    int xr = w-w/8;
    int yt = fonth;
    int yb = fonth + (int)(scale*dmax);

    int levelw = xr-xl;
    int levelh = yb-yt;

    // clear the background of the Level
    g.setColor(lbg);
    g.fillRect(xl, yt, levelw, levelh);

    // fill the Level with according to the value
    // calculate the 10log of value:
    double dvalue = 0.0;
    if (value != 0.0)
    {
        dvalue = Math.log(value) / Math.log(10);
    }

    int l = (int) (scale * dvalue);
    g.setColor(lfg);
    g.fillRect(xl+2, yb-l, levelw-4, l);

    g.setColor(fg);
    if (doScale)
    {
        drawScale(g, xl, xr, yt, yb, scale);
    }

    // draw the value
    int sw = fm.stringWidth(value+" B/s");
    int p = xl + (levelw-sw)/2;
    g.drawString(value+" B/s", p, yb-l-2);
}

private void drawScale (Graphics g, int xl, int xr, int yt, int yb, 
    int scale)
{
    int sw, p;
    int y=yb;
    int x=xl;
    for (int i=0; i<= dmax; i++)
    {
        g.drawLine(x-2, y, x+2, y);

        sw = fm.stringWidth(xaxis[i]);
        p = (x-2) - sw -2;
        g.drawString(xaxis[i], p, y);
        y -=scale;
    }

    // the last label
    y=yt;
    g.drawLine(x-2, y, x+2, y);
    sw = fm.stringWidth(xaxis[6]);
    p = (x-2) - sw -2;
    g.drawString(xaxis[6], p, y);
}


/**
 * Returns the preferred size of the button. 
 */
public Dimension getPreferredSize() 
{
    int w = 20;
    int h = 100;

    if (doScale)
    {
        w = w*3;
    }
    return new Dimension(w, h);
}

/**
 * Returns the minimum size of the button. 
 */
public Dimension getMinimumSize() 
{
    int w = 10;
    int h = 75;

    if (doScale)
    {
        w = w*3;
    }
    return new Dimension(w, h);
}

public String toString()
{
    return getClass().getName()
        + "["
        + ",value=" + value
        + "]";
}

}