Draw a pie chartTag(s): AWT


import java.util.*;
import java.awt.*;
import java.applet.Applet;

public class Graph extends Applet {
 int    depth, radius;

public void init() {
  float value;
  String at = getParameter("width");
  radius = (at != null) ?  Integer.valueOf(at).intValue() : 100;
  at = getParameter("depth");
  depth = (at != null) ? Integer.valueOf(at).intValue() : 20;
  at = getParameter("values");
  PieChartCanvas c = new PieChartCanvas(radius, depth);
  setLayout(new BorderLayout());

  // Create Hashtable to map color name (String) to Color type
  Hashtable colors = new Hashtable();
  colors.put("green", Color.green);
  colors.put("red", Color.red);
  colors.put("blue", Color.blue);
  colors.put("yellow", Color.yellow);
  colors.put("magenta", Color.magenta);
  colors.put("cyan", Color.cyan);
  colors.put("orange", Color.orange);
  colors.put("pink", Color.pink);
  colors.put("white", Color.white);
  colors.put("black", Color.black);

  // "value-color,value-color,..." 
  StringTokenizer t = new StringTokenizer(at, ","); 
  String s;
  int i;
  while (t.hasMoreTokens()) {
    s = t.nextToken();
    i = s.indexOf('-');
    value = Float.valueOf(s.substring(0, i)).floatValue();
    c.addSlice(value, (Color)colors.get(s.substring(i + 1)));
   }

  resize(c.getMinimumSize().width, c.getMinimumSize().height);
  add("Center", c);
  }
}

class PieChartCanvas extends Canvas {
  /*
  ** author     Ciaran Treanor  ciaran@broadcom.ie
  */
  final double aspectFudge = 2.5;
  int radius, depth, called = 1, numSlices = 0;
  float total = 0, value[] = new float[10];
  Color color[] = new Color[10];
  Graphics offGraphics;
  Image gfxBuff;

  public PieChartCanvas(int radius, int depth) {
    this.value = value;
    this.color = color;
    this.radius = radius;
    this.depth = depth;
    }

  public void paint(Graphics g) {
    int startAngle;
    float angle;
    Dimension d = getSize();

    if(gfxBuff == null) {
      gfxBuff = createImage(d.width, d.height);
      offGraphics = gfxBuff.getGraphics();
      offGraphics.setColor(getBackground());
      offGraphics.fillRect(0, 0, d.width, d.height);
      }

    // do the 3d effect
    for(int x = depth; x >= 1; x--) {
      startAngle = -45;
      for(int i = 0; i < numSlices; i++) {
        offGraphics.setColor(color[i].darker());
        angle = Math.round(360 * (value[i] / total));
        offGraphics.fillArc(0, x, radius, (int)(radius / aspectFudge),
            startAngle, (int)angle);
            startAngle += angle;
        }
    }

    // draw the pie slice
    startAngle = -45;
    for(int i = 0; i < numSlices; i++) {
      offGraphics.setColor(color[i]);
      angle = Math.round(360 * (value[i] / total));
      offGraphics.fillArc(0, 0, radius, (int)(radius / aspectFudge),
         startAngle, (int)angle);
         startAngle += angle;
      }
    g.drawImage(gfxBuff, 0, 0, null);
    }

  public void addSlice(float value, Color color) {
    this.value[numSlices] = value;
    this.color[numSlices++] = color;
    total += value;
    }

  public Dimension getPreferredSize() {
    return getMinimumSize();
    }

  public Dimension getMinimumSize() {
    return new Dimension(radius, (int)((radius / aspectFudge) + depth));
    }
}
[JavaPie.hmtl]
<HTML>
<TABLE><TR><TD>
<APPLET CODE=Graph.class WIDTH=150 HEIGHT=150>
  <PARAM NAME="depth"  VALUE="30">
  <PARAM NAME="width"  VALUE="120">
  <PARAM NAME="values" VALUE="1-red,5-green,7-blue">
</APPLET>
<TD>
<TABLE>
<TR><TD>item 1<TD BGCOLOR="#FF0000">  
<TR><TD>item 2<TD BGCOLOR="#008000">  
<TR><TD>item 3<TD BGCOLOR="#0000FF">  
</TABLE>
</TABLE>
</HMTL>
Try it here
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