textline.java

java 作图的程序

package graph;

import java.awt.*;
import java.util.*;
import java.lang.*;
import java.awt.image.*;

/*
**************************************************************************
**
**    Class  TextLine
**
**************************************************************************
**    Copyright (C) 1996 Leigh Brookshaw
**
**    This program 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 program 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 program; if not, write to the Free Software
**    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
**************************************************************************
**
**    This class is designed to bundle together all the information required
**    to draw short Strings
**
*************************************************************************/

/**
 * This class is designed to bundle together all the information required
 * to draw short Strings with subscripts and superscripts
 *
 * @version $Revision: 1.10 $, $Date: 1996/09/05 04:53:27 $
 * @author  Leigh Brookshaw
 */

public class TextLine extends Object {

/*
*************
**
** Constants
**
************/
  /**
   * Center the Text over the point
   */
     public final static int CENTER   =    0;
  /**
   * Position the Text to the Left of the  point
   */
     public final static int LEFT     =    1;
  /**
   * Position the Text to the Right of the  point
   */
     public final static int RIGHT    =    2;
  /**
   * Format to use when parsing a double
   */
     public final static int SCIENTIFIC = 1;
  /**
   * Format to use when parsing a double
   */
     public final static int ALGEBRAIC = 2;


  /*
  ** Minimum Point size allowed for script characters
  */
     final static int MINIMUM_SIZE  =  6;

/*
**********************
**
** Protected Variables
**
*********************/
  /**
   * Decrease in size of successive script levels
   */
     protected double script_fraction = 0.8;
  /**
   * Superscript offset
   */
     protected double sup_offset      = 0.6;
  /**
   * Subscript offset
   */
     protected double sub_offset      = 0.7;
  /**
   * Font to use for text
   */
     protected Font font     = null;
  /**
   * Text color
   */
     protected Color color   = null;
  /**
   * Background Color
   */
     protected Color background   = null;
  /**
   * The text to display
   */
     protected String text   = null;
  /**
   * The logical name of the font to use
   */
     protected String fontname  = "TimesRoman";
  /**
   * The font size
   */
     protected int    fontsize  = 0;
  /**
   * The font style
   */
     protected int    fontstyle = Font.PLAIN;
  /**
   * Text justification. Either CENTER, LEFT or RIGHT
   */
     protected int    justification = LEFT;
  /**
   * The width of the text using the current Font
   */
     protected int width   = 0;
  /**
   * The ascent using the current font
   */
     protected int ascent  = 0;
  /**
   * The maximum ascent using the current font
   */
     protected int maxAscent  = 0;
  /**
   * The descent using the current font
   */
     protected int descent = 0;
  /**
   * The maximum descent using the current font
   */
     protected int maxDescent = 0;
  /**
   * The height using the current font ie ascent+descent+leading
   */
     protected int height = 0;
  /**
   * The leading using the current font
   */
     protected int leading = 0;
  /**
   * Has the string been parsed! This only needs to be done once
   * unless the font is altered.
   */
     protected boolean parse = true;

  /**
   * Local graphics context.
   */
     protected Graphics lg = null;
  /**
   * The parsed string. Each element in the vector represents
   * a change of context in the string ie font change and offset.
   */
     protected Vector list = new Vector(8,4);

/*
**********************
**
** Constructors
**
*********************/

  /**
   * Instantiate the class
   */
     public TextLine() { }
  /**
   * Instantiate the class.
   * @param s String to parse.
   */
     public TextLine(String s) { 
            this.text = s;
	  }
  /**
   * Instantiate the class
   * @param s String to parse.
   * @param f Font to use.
   */

     public TextLine(String s, Font f) { 
            this(s);
            font      = f;
            if(font == null) return;
            fontname  = f.getName();
            fontstyle = f.getStyle();
            fontsize  = f.getSize();
	  }
  /**
   * Instantiate the class
   * @param s String to parse.
   * @param f Font to use.
   * @param c Color to use
   * @param j Justification
   */

     public TextLine(String s, Font f, Color c, int j) {
            this(s,f);
            color  = c;
            justification = j;
 	  }

  /**
   * Instantiate the class
   * @param s String to parse.
   * @param c Color to use
   */
     public TextLine(String s, Color c) { 
            this(s);
            color = c;
	  }
  /**
   * Instantiate the class
   * @param f Font to use.
   * @param c Color to use
   * @param j Justification
   */

     public TextLine(Font f, Color c, int j) {
            font      = f;
            color  = c;
            justification = j;

            if(font == null) return;
            fontname  = f.getName();
            fontstyle = f.getStyle();
            fontsize  = f.getSize();
 	  }

/*
*****************
**
** Public Methods
**
*****************/


  /**
   * Create a New Textline object copying the state of the existing
   * object into the new one. The state of the class is the color,
   * font, and justification ie everything but the string.
   */

     public TextLine copyState() {
            return new TextLine(font,color,justification);
     }

  /**
   * Copy the state of the parsed Textline into the existing
   * object.
   * @param t The TextLine to get the state information from.
   */
     public void copyState(TextLine t) {
            if(t==null) return;

            font  = t.getFont();
            color = t.getColor();
            justification = t.getJustification();
       
            if(font == null) return;
            fontname  = font.getName();
            fontstyle = font.getStyle();
            fontsize  = font.getSize();

            parse  = true;
     }
  /**
   * Set the Font to use with the class
   * @param f Font
   */
     public void setFont(  Font f   ) { 
            font      = f;
            fontname  = f.getName();
            fontstyle = f.getStyle();
            fontsize  = f.getSize();
            parse = true; 

     }
  /**
   * Set the String to use with the class
   * @param s String
   */
     public void setText(  String s ) { 
            text   = s;
            parse = true; 
     }

  /**
   * Set the Color to use with the class
   * @param c Color
   */
     public void setColor( Color c  ) { 
            color = c; 
     }
  /**
   * Set the Background Color to use with the class
   * @param c Color
   */
     public void setBackground( Color c  ) { 
            background = c; 
     }


  /**
   * Set the Justification to use with the class
   * @param t Justification
   */
     public void setJustification( int i ) {
          switch (i) {
          case CENTER:
                    justification = CENTER;
                    break;
          case LEFT: default:
                    justification = LEFT;
                    break;
          case RIGHT:
                    justification = RIGHT;
                    break;
          }
	}


  /**
   * @return the font the class is using
   */
     public Font   getFont()  { 
                                return font; 
     }
  /**
   * @return the String the class is using.
   */
     public String getText()  { 
                               return text; 
     }

  /**
   * @return the Color the class is using.
   */
     public Color  getColor() { 
                               return color; 
     }
  /**
   * @return the Background Color the class is using.
   */
     public Color  getBackground() { 
                               return background; 
     }
  /**
   * @return the Justification the class is using.
   */
     public int    getJustification() { 
                                return justification; 
     }

  /**
   * @param g Graphics context.
   * @return the Fontmetrics the class is using.
   */
     public FontMetrics getFM(Graphics g) {
         if(g==null) return null;

         if(font==null) return g.getFontMetrics();
         else           return g.getFontMetrics(font);
     }

  /**
   * @param g Graphics context.
   * @param ch The character.
   * @return the width of the character.
   */
     public int charWidth(Graphics g, char ch) {
         FontMetrics fm;
         if(g==null) return 0;

         if(font==null) fm =  g.getFontMetrics();
         else           fm =  g.getFontMetrics(font);
         
         return fm.charWidth(ch);
     }

  /**
   * @param g Graphics context.
   * @return the width of the parsed text.
   */
     public int getWidth(Graphics g) {

         parseText(g);

         return width;

     }

  /**
   * @param g Graphics context.
   * @return the height of the parsed text.
   */
     public int getHeight(Graphics g) {

         parseText(g);

         return height;

     }


  /**
   * @param g Graphics context.
   * @return the ascent of the parsed text.
   */
     public int getAscent(Graphics g) {
         if(g == null) return 0;

         parseText(g);

         return ascent;
     }
  /**
   * @param g Graphics context.
   * @return the maximum ascent of the parsed text.
   */
     public int getMaxAscent(Graphics g) {
         if(g == null) return 0;

         parseText(g);

         return maxAscent;
     }

  /**
   * @param g Graphics context.
   * @return the descent of the parsed text.
   */
     public int getDescent(Graphics g) {
         if(g == null) return 0;

         parseText(g);

         return descent;
      
     }
  /**
   * @param g Graphics context.
   * @return the maximum descent of the parsed text.
   */
     public int getMaxDescent(Graphics g) {
         if(g == null) return 0;

         parseText(g);

         return maxDescent;
     }


  /**
   * @param g Graphics context.
   * @return the leading of the parsed text.
   */
     public int getLeading(Graphics g) {