/* TransformPanel class */import java.util.StringTokenizer;import java.awt.*;import java.io.*;import java.net.*;/** * Text panel to display the source code of the animation algorithm. * This class is initialized in the <code>TextFrame</code> class * construction during the main frame initialization. * Each line of the source code starting with <code>/*-</code> will be ignored. * The line after <code>/*-------</code> is considered as the first line of * text being displayed. * The line before <code>//-</code> is the last line of source code being * displayed. The text after this line will no longer be parsed. * See also <A href="AlgThread.html"><code>AlgThread</code></A> for special * symbol used in displaying source code in text panel. * <p> * This method should NOT have to be called manually. * @see TextFrame * @see AlgAnimFrame */public class TransformPanel extends Panel {    String file_name;    private boolean highlighted;    private int width = 300;    private int height = 400;		private BlockDiagram bd;    private Dimension offscreensize = null;    private Image offscreen = null;    private Graphics offGraphics = null;    private static final int dx = 2;    private Font font;    private int font_size = 10;    private int line_space = 14;    private int start;    private void SetFont( Graphics g ) {        FontMetrics fm;        this.setBackground( Color.white );        font = new Font( "Dialog", Font.PLAIN, font_size );        fm = g.getFontMetrics( font );        line_space = fm.getHeight() + 1;        g.setFont( font );    }    private int ReadSource( DataInputStream ds ) {        int cnt = 0;        StringBuffer sb;                        try {            while( true ) {                String s;                if ( (s = ds.readLine()) != null ) {                   // if ( s.startsWith( start_sign ) ) {                   //     n_lines = 0;                   //     cnt = 0;                   // } else if (s.trim().startsWith(ignore_trigger)) {                   //     continue;                   // } else if (s.startsWith(end_sign)) {                   //     break;                   // } else {                   //     sb = trim( s );                   //     /* Copy the buffer into a string */                   //     lines[cnt++] = expandtabs( sb );                   // }                 } else                    break;            }        } catch( IOException e ) {}        return cnt;    }		public TransformPanel( int number, boolean before ) {			System.out.println("TransformPanel(" + number + "," +                                              before + ")" );			bd = new BlockDiagram( number, before );			if ( bd == null ) {				System.out.println("null blockdiagram");				}			highlighted = false;						}    /**     * Creates a text panel based on the source file specified in the String     * passed in as the parameter.     * @param fn Filename of the source code     */    public TransformPanel( String fn ) {        FileInputStream instream;        file_name = fn;        File source = new File( file_name );                if ( source.exists() && source.isFile() ) {            try {                // lines = new String[ max_lines ];                instream = new FileInputStream( source );            } catch( IOException e ) {}            /* Read the file */        } else            System.out.println("Cant access [" + file_name + "]");    }            /**     * Creates a text frame based on the URL specified by     * the parameter.     * @param sourceURL URL of the source code     * @see URL     */    public TransformPanel( URL sourceURL) {        InputStream source = null;        StringBuffer sb;        // n_lines = 0;				// start = 0;        // file_name = sourceURL.toString();				try {	   			 source = sourceURL.openStream();				} catch( IOException e ) {       	}        if ( source != null ) {          //   lines = new String[ max_lines ];           //  /* Read the file */           //  DataInputStream ds = new DataInputStream( source );           //  n_lines = ReadSource( ds );        }                                 // highlight = -1;            }    public void Highlight( int h ) {        highlighted = h == 0;        this.repaint();    }    /**     * Returns the initial dimension of the text panel. This method     * will be called by the layout manager during the corresponding     * frame initialization.     */    public Dimension getPreferredSize() {        // int h = line_space * (n_lines + 1) - start * line_space;        int h = 200;        return new Dimension( width, h );    }        /**     * Return the minimum allowed dimension of the text panel.     */    public Dimension getMinimumSize() {        // int h = line_space * (n_lines + 1) - start * line_space;        int h = 140;        return new Dimension( width, h );    }        /**     * This method is invoked when the <code>repaint()</code> method of the     * parent class is called. This method eliminates flashing during animation.     */    public void update(Graphics g) {        Dimension d = size();        if (d.width < 1 || d.height < 1)            return;        if ((offscreen == null) || (d.width != offscreensize.width) ||                (d.height != offscreensize.height)) {            offscreen = createImage(d.width, d.height);            offscreensize = d;            offGraphics = offscreen.getGraphics();        }        offGraphics.setColor(Color.white);        offGraphics.fillRect(0, 0, d.width, d.height);        paint(offGraphics);        g.drawImage(offscreen, 0, 0, null);    }        /**     * Set the first line to display.     * @param start First line to display     * @see TransformPanel#getStart     */    // public void setStart(int start) {		//		this.start = start;    // }    /**     * This method print the source code starting from the first line specified     * by <code>setStart(int)</code> on the text panel.     * @param g Graphical context of the text panel.     */    public void paint( Graphics g ) {        int i, x, y;        SetFont( g );        x = dx; y = line_space;        g.setColor( Color.black );        bd.draw( g );    }    /**     * Get the number of lines of source code to be displayed on the text panel.     * @return The number of lines of source code to be displayed on the      *		text frame.     */    public int getNumLines() {	return 0;    	}    /**     * Get the number of pixels used by each line of text.     * @return The number of pixels allocated for each line of text.     */    public int getLineSpace() {			return line_space;    }    /**     * Get the first line of the source code that will be displayed.     * This attribute is used to couple the text panel to a vertical scrollbar     * in the TextFrame.      * @return The first line of source code that will be displayed.     *      */    public int getStart() {			return start;    }		public void setStart( int s ) {			// not relevant to TransformPanel			}}