graph2d.java

java 作图的程序

	       } else {
                                    xrange = Math.max(range, xrange);
               }
            }

            if(xrange <= 0 | yrange <= 0 )      return r; 


            if( xrange > yrange )      range = xrange;
            else                       range = yrange;

            for (int i=0; i<axis.size(); i++) {
               a = (Axis)axis.elementAt(i);
               a.maximum = a.minimum + range;
            }
/*
**          Get the new data rectangle
*/
            dr = getDataRectangle(g, r);
/*
**          Modify the data rectangle so that it is square.
*/
	    if(dr.width > dr.height) {
                    x += (dr.width-dr.height)/2.0;
                    width -= dr.width-dr.height;
            } else {
                    y += (dr.height-dr.width)/2.0;
                    height -= dr.height-dr.width;
            }


            return new Rectangle(x,y,width,height);


	}
/**
 *  Calculate the rectangle occupied by the data
 */

       protected Rectangle getDataRectangle(Graphics g, Rectangle r) {
            Axis a;
            int waxis;
            int x     = r.x;
            int y     = r.y;
            int width = r.width;
            int height = r.height;

            for (int i=0; i<axis.size(); i++) {
               a = ((Axis)axis.elementAt(i));
 
               waxis = a.getAxisWidth(g);

               switch (a.getAxisPos()) {
               case Axis.LEFT:
                          x += waxis;
                          width -= waxis;
                          break;
               case Axis.RIGHT:
                          width -= waxis;
                          break;
               case Axis.TOP:
                          y += waxis;
                          height -= waxis;
                          break;
               case Axis.BOTTOM:
                          height -= waxis;
                          break;
               }
            }

             return new Rectangle(x, y, width, height);
            }

/**
 *
 *  Draw the Axis. As each axis is drawn and aligned less of the canvas
 *  is avaliable to plot the data. The returned Rectangle is the canvas
 *  area that the data is plotted in.
 */
        protected Rectangle drawAxis(Graphics g, Rectangle r) {
            Axis a;
            int waxis;
            Rectangle dr;
            int x;
            int y;
            int width;
            int height;


            if(square) r = ForceSquare(g,r);

            dr = getDataRectangle(g,r);

            x      = dr.x;
            y      = dr.y;
            width  = dr.width;
            height = dr.height;

            if(clearAll ) {
               Color c = g.getColor();
	       g.setColor(DataBackground);
               g.fillRect(x,y,width,height);
               g.setColor(c);
            }

// Draw a frame around the data area (If requested)
            if(frame) drawFrame(g,x,y,width,height);

// Now draw the axis in the order specified aligning them with the final
// data area.
            for (int i=0; i<axis.size(); i++) {
               a = ((Axis)axis.elementAt(i));

               a.data_window = new Dimension(width,height);

               switch (a.getAxisPos()) {
               case Axis.LEFT:
                          r.x += a.width;
                          r.width -= a.width;
                          a.positionAxis(r.x,r.x,y,y+height);
                          if(r.x == x ) {
                             a.gridcolor = gridcolor;
                             a.drawgrid  = drawgrid;
                             a.zerocolor = zerocolor;
                             a.drawzero  = drawzero;
			   }

                           a.drawAxis(g);

                           a.drawgrid  = false;
                           a.drawzero  = false;

                          break;
               case Axis.RIGHT:
                          r.width -= a.width;
                          a.positionAxis(r.x+r.width,r.x+r.width,y,y+height);
                          if(r.x+r.width == x+width ) {
                             a.gridcolor = gridcolor;
                             a.drawgrid  = drawgrid;
                             a.zerocolor = zerocolor;
                             a.drawzero  = drawzero;
                          }

                          a.drawAxis(g);

                          a.drawgrid  = false;
                          a.drawzero  = false;

                           break;
               case Axis.TOP:
                          r.y += a.width;
                          r.height -= a.width;
                          a.positionAxis(x,x+width,r.y,r.y);
                          if(r.y == y) {
                             a.gridcolor = gridcolor;
                             a.drawgrid  = drawgrid;
                             a.zerocolor = zerocolor;
                             a.drawzero  = drawzero;
                          }

                          a.drawAxis(g);

                          a.drawgrid  = false;
                          a.drawzero  = false;


                          break;
               case Axis.BOTTOM:
                          r.height -= a.width;
                          a.positionAxis(x,x+width,r.y+r.height,r.y+r.height);
                          if(r.y +r.height == y+height ) {
                             a.gridcolor = gridcolor;
                             a.drawgrid  = drawgrid;
                             a.zerocolor = zerocolor;
                             a.drawzero  = drawzero;
                          }

                          a.drawAxis(g);

                          a.drawgrid  = false;
                          a.drawzero  = false;


                          break;
               }
            }

           return r;
      }
/*
 *  Draws a frame around the data area.
 */
      protected void drawFrame(Graphics g, int x, int y, int width, int height) {
        Color c = g.getColor();

        if( framecolor != null ) g.setColor(framecolor);

        g.drawRect(x,y,width,height);

        g.setColor(c);


     }



}

/**
 * This should be thrown if any of the packages fileloaders 
 * encounter a format error
*/
class FileFormatException extends Exception {
    public FileFormatException(String s) {
        super(s);
    }
}



/**
 *   This is a separate thread that flashes a message
 *   on the Graph2D canvas that data is loading
 */

class LoadMessage extends Thread {
        Graph2D  g2d;
        String   message    = "Loading Data ... Please Wait!";
        String   newmessage = null;
        long     visible    = 500;
        long     invisible  = 200;
        Color    foreground = Color.red;
        Graphics lg = null;
        Font     f = null;
        
/**
 *    Instantiate the class
 * @param g2d The Graph2D canvas to draw message on
 *
 */            
        public LoadMessage(Graph2D g2d) {
           this.g2d = g2d;

        }

/**
 *  Instantiate the class
 * @param g2d The Graph2D canvas to draw message on
 * @param s   The string to flash on the canvas
 */            
        public LoadMessage(Graph2D g2d, String s) {

           this(g2d);
           this.message = s;

        }
/**
 *  Instantiate the class
 * @param g2d The Graph2D canvas to draw message on
 * @param s   The string to flash on the canvas
 * @param visible Number of milliseconds the message is visible
 * @param invisible Number of milliseconds the message is invisible
 */            

        public LoadMessage(Graph2D g, String s, long visible, long invisible) {
            this(g,s);
            this.visible = visible;
            this.invisible = invisible;
        }

/**
 *   begin displaying the message
 */
        public void begin() {
 
            g2d.clearAll = false;
            g2d.paintAll = false;

            super.start();

	  }
/**
 *   end displaying message and force a graph repaint
 */
        public void end() {
             
            super.stop();

            g2d.clearAll = true;
            g2d.paintAll = true;

            if(lg != null) lg.dispose();

            g2d.repaint();

	  }
/**
 *   The method to call when the thread starts
 */
        public void run() {
           boolean draw = true;
           FontMetrics fm;
           Rectangle r;
           int sw = 0;
           int sa = 0;
           int x  = 0;
           int y  = 0;

           setPriority(Thread.MIN_PRIORITY);

           
           while(true) {

                if( newmessage != null && draw) {
                    message = newmessage;
                    newmessage = null;
		}

                if(lg == null) {           
                  lg = g2d.getGraphics();
                  if(lg != null) lg = lg.create();
	        }

                if( lg != null) {
                   if(f != null) lg.setFont(f);
                   fm = lg.getFontMetrics(lg.getFont());
                   sw = fm.stringWidth(message);
                   sa = fm.getAscent();
		} else {
                   draw = false;
		 }

                if( draw ) {
                      lg.setColor(foreground);
                      r = g2d.bounds();
                      x = r.x + (r.width-sw)/2;
                      y = r.y + (r.height+sa)/2;
                      lg.drawString(message, x, y);
                
                      g2d.repaint();

                      try { sleep(visible); }
                      catch(Exception e) { }
	        } else {
                      if(lg != null) {
                         lg.setColor(g2d.getBackground());
                         lg.drawString(message, x, y);

                         g2d.repaint();
		       }

                       try { sleep(invisible); }
                       catch(Exception e) { }

		 }

                draw = !draw;

	      }
	 }

  /**
   * Set the font the message will be displayed in
   * @param f the font
   */
          public void setFont(Font f) {
              this.f = f;
          }
  /**
   *  The foreground color for the message
   * @param c the foreground color
   */

          public void setForeground(Color c) {
              if(c == null) return;
              this.foreground = c;
          }
  /**
   *   Set the message to be displayed
   * @param s the message
   */

          public void setMessage(String s) {
              if(s==null) return;
              newmessage = s;
          }


}