mirror of git://gcc.gnu.org/git/gcc.git
				
				
				
			
		
			
				
	
	
		
			731 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			Java
		
	
	
	
			
		
		
	
	
			731 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			Java
		
	
	
	
/* Utilities.java --
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   Copyright (C) 2004, 2005, 2006  Free Software Foundation, Inc.
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This file is part of GNU Classpath.
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GNU Classpath is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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						|
the Free Software Foundation; either version 2, or (at your option)
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						|
any later version.
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GNU Classpath is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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						|
General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with GNU Classpath; see the file COPYING.  If not, write to the
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Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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02110-1301 USA.
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Linking this library statically or dynamically with other modules is
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making a combined work based on this library.  Thus, the terms and
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						|
conditions of the GNU General Public License cover the whole
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combination.
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As a special exception, the copyright holders of this library give you
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permission to link this library with independent modules to produce an
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executable, regardless of the license terms of these independent
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modules, and to copy and distribute the resulting executable under
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terms of your choice, provided that you also meet, for each linked
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independent module, the terms and conditions of the license of that
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module.  An independent module is a module which is not derived from
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or based on this library.  If you modify this library, you may extend
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this exception to your version of the library, but you are not
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obligated to do so.  If you do not wish to do so, delete this
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exception statement from your version. */
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package javax.swing.text;
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import java.awt.FontMetrics;
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import java.awt.Graphics;
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import java.awt.Point;
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import java.text.BreakIterator;
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import javax.swing.text.Position.Bias;
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/**
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 * A set of utilities to deal with text. This is used by several other classes
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 * inside this package.
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 *
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 * @author Roman Kennke (roman@ontographics.com)
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 * @author Robert Schuster (robertschuster@fsfe.org)
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 */
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public class Utilities
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{
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  /**
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   * Creates a new <code>Utilities</code> object.
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   */
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  public Utilities()
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  {
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    // Nothing to be done here.
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  }
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  /**
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   * Draws the given text segment. Contained tabs and newline characters
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   * are taken into account. Tabs are expanded using the
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   * specified {@link TabExpander}.
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   *
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   *
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   * The X and Y coordinates denote the start of the <em>baseline</em> where
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   * the text should be drawn.
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   *
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   * @param s the text fragment to be drawn.
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   * @param x the x position for drawing.
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   * @param y the y position for drawing.
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   * @param g the {@link Graphics} context for drawing.
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   * @param e the {@link TabExpander} which specifies the Tab-expanding
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   *     technique.
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   * @param startOffset starting offset in the text.
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   * @return the x coordinate at the end of the drawn text.
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   */
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  public static final int drawTabbedText(Segment s, int x, int y, Graphics g,
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                                         TabExpander e, int startOffset)
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  {
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    // This buffers the chars to be drawn.
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    char[] buffer = s.array;
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    // The font metrics of the current selected font.
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    FontMetrics metrics = g.getFontMetrics();
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    int ascent = metrics.getAscent();
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    // The current x and y pixel coordinates.
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    int pixelX = x;
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    int pos = s.offset;
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    int len = 0;
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    int end = s.offset + s.count;
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    for (int offset = s.offset; offset < end; ++offset)
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      {
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        char c = buffer[offset];
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        switch (c)
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          {
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          case '\t':
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            if (len > 0) {
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              g.drawChars(buffer, pos, len, pixelX, y);
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              pixelX += metrics.charsWidth(buffer, pos, len);
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              len = 0;
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            }
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            pos = offset+1;
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            if (e != null)
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              pixelX = (int) e.nextTabStop((float) pixelX, startOffset + offset
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                                           - s.offset);
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            else
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              pixelX += metrics.charWidth(' ');
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            x = pixelX;
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            break;
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          case '\n':
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          case '\r':
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            if (len > 0) {
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              g.drawChars(buffer, pos, len, pixelX, y);
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              pixelX += metrics.charsWidth(buffer, pos, len);
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              len = 0;
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            }
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            x = pixelX;
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            break;
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          default:
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            len += 1;
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          }
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      }
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    if (len > 0)
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      {
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        g.drawChars(buffer, pos, len, pixelX, y);
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        pixelX += metrics.charsWidth(buffer, pos, len);
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      }
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    return pixelX;
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  }
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  /**
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   * Determines the width, that the given text <code>s</code> would take
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   * if it was printed with the given {@link java.awt.FontMetrics} on the
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   * specified screen position.
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   * @param s the text fragment
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   * @param metrics the font metrics of the font to be used
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   * @param x the x coordinate of the point at which drawing should be done
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   * @param e the {@link TabExpander} to be used
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   * @param startOffset the index in <code>s</code> where to start
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   * @returns the width of the given text s. This takes tabs and newlines
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   * into account.
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   */
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  public static final int getTabbedTextWidth(Segment s, FontMetrics metrics,
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                                             int x, TabExpander e,
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                                             int startOffset)
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  {
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    // This buffers the chars to be drawn.
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    char[] buffer = s.array;
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    // The current x coordinate.
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    int pixelX = x;
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    // The current maximum width.
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    int maxWidth = 0;
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    int end = s.offset + s.count;
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    int count = 0;
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    for (int offset = s.offset; offset < end; offset++)
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      {
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        switch (buffer[offset])
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          {
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          case '\t':
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            // In case we have a tab, we just 'jump' over the tab.
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            // When we have no tab expander we just use the width of 'm'.
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            if (e != null)
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              pixelX = (int) e.nextTabStop(pixelX,
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                                           startOffset + offset - s.offset);
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            else
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              pixelX += metrics.charWidth(' ');
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            break;
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          case '\n':
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            // In case we have a newline, we must 'draw'
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            // the buffer and jump on the next line.
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            pixelX += metrics.charsWidth(buffer, offset - count, count);
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            count = 0;
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            break;
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          default:
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            count++;
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          }
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      }
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    // Take the last line into account.
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    pixelX += metrics.charsWidth(buffer, end - count, count);
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    return pixelX - x;
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  }
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  /**
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   * Provides a facility to map screen coordinates into a model location. For a
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   * given text fragment and start location within this fragment, this method
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   * determines the model location so that the resulting fragment fits best
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   * into the span <code>[x0, x]</code>.
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   *
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   * The parameter <code>round</code> controls which model location is returned
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   * if the view coordinates are on a character: If <code>round</code> is
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   * <code>true</code>, then the result is rounded up to the next character, so
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   * that the resulting fragment is the smallest fragment that is larger than
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   * the specified span. If <code>round</code> is <code>false</code>, then the
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   * resulting fragment is the largest fragment that is smaller than the
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   * specified span.
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   *
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   * @param s the text segment
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   * @param fm the font metrics to use
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   * @param x0 the starting screen location
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   * @param x the target screen location at which the requested fragment should
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   *        end
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   * @param te the tab expander to use; if this is <code>null</code>, TABs are
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   *        expanded to one space character
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   * @param p0 the starting model location
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   * @param round if <code>true</code> round up to the next location, otherwise
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   *        round down to the current location
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   *
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   * @return the model location, so that the resulting fragment fits within the
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   *         specified span
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   */
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  public static final int getTabbedTextOffset(Segment s, FontMetrics fm, int x0,
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                                              int x, TabExpander te, int p0,
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                                              boolean round)
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  {
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    int found = s.count;
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    int currentX = x0;
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    int nextX = currentX;
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    int end = s.offset + s.count;
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    for (int pos = s.offset; pos < end && found == s.count; pos++)
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      {
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        char nextChar = s.array[pos];
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        if (nextChar != '\t')
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          nextX += fm.charWidth(nextChar);
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        else
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          {
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            if (te == null)
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              nextX += fm.charWidth(' ');
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            else
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              nextX += ((int) te.nextTabStop(nextX, p0 + pos - s.offset));
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          }
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        if (x >= currentX && x < nextX)
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          {
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            // Found position.
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            if ((! round) || ((x - currentX) < (nextX - x)))
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              {
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                found = pos - s.offset;
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              }
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            else
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              {
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                found = pos + 1 - s.offset;
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              }
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          }
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        currentX = nextX;
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      }
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    return found;
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  }
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  /**
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   * Provides a facility to map screen coordinates into a model location. For a
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						|
   * given text fragment and start location within this fragment, this method
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						|
   * determines the model location so that the resulting fragment fits best
 | 
						|
   * into the span <code>[x0, x]</code>.
 | 
						|
   *
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   * This method rounds up to the next location, so that the resulting fragment
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   * will be the smallest fragment of the text, that is greater than the
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   * specified span.
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   *
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   * @param s the text segment
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   * @param fm the font metrics to use
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						|
   * @param x0 the starting screen location
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						|
   * @param x the target screen location at which the requested fragment should
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						|
   *        end
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						|
   * @param te the tab expander to use; if this is <code>null</code>, TABs are
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						|
   *        expanded to one space character
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   * @param p0 the starting model location
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   *
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   * @return the model location, so that the resulting fragment fits within the
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   *         specified span
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   */
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  public static final int getTabbedTextOffset(Segment s, FontMetrics fm, int x0,
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                                              int x, TabExpander te, int p0)
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  {
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    return getTabbedTextOffset(s, fm, x0, x, te, p0, true);
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  }
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  /**
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   * Finds the start of the next word for the given offset.
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   *
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   * @param c
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   *          the text component
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   * @param offs
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   *          the offset in the document
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   * @return the location in the model of the start of the next word.
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   * @throws BadLocationException
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   *           if the offset is invalid.
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   */
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  public static final int getNextWord(JTextComponent c, int offs)
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      throws BadLocationException
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  {
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    if (offs < 0 || offs > (c.getText().length() - 1))
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      throw new BadLocationException("invalid offset specified", offs);
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    String text = c.getText();
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    BreakIterator wb = BreakIterator.getWordInstance();
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    wb.setText(text);
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    int last = wb.following(offs);
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    int current = wb.next();
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    int cp;
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    while (current != BreakIterator.DONE)
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      {
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        for (int i = last; i < current; i++)
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          {
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            cp = text.codePointAt(i);
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            // Return the last found bound if there is a letter at the current
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            // location or is not whitespace (meaning it is a number or
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            // punctuation). The first case means that 'last' denotes the
 | 
						|
            // beginning of a word while the second case means it is the start
 | 
						|
            // of something else.
 | 
						|
            if (Character.isLetter(cp)
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                || !Character.isWhitespace(cp))
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              return last;
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          }
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        last = current;
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        current = wb.next();
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      }
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    throw new BadLocationException("no more words", offs);
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  }
 | 
						|
 | 
						|
  /**
 | 
						|
   * Finds the start of the previous word for the given offset.
 | 
						|
   *
 | 
						|
   * @param c
 | 
						|
   *          the text component
 | 
						|
   * @param offs
 | 
						|
   *          the offset in the document
 | 
						|
   * @return the location in the model of the start of the previous word.
 | 
						|
   * @throws BadLocationException
 | 
						|
   *           if the offset is invalid.
 | 
						|
   */
 | 
						|
  public static final int getPreviousWord(JTextComponent c, int offs)
 | 
						|
      throws BadLocationException
 | 
						|
  {
 | 
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    String text = c.getText();
 | 
						|
 | 
						|
    if (offs <= 0 || offs > text.length())
 | 
						|
      throw new BadLocationException("invalid offset specified", offs);
 | 
						|
 | 
						|
    BreakIterator wb = BreakIterator.getWordInstance();
 | 
						|
    wb.setText(text);
 | 
						|
    int last = wb.preceding(offs);
 | 
						|
    int current = wb.previous();
 | 
						|
    int cp;
 | 
						|
 | 
						|
    while (current != BreakIterator.DONE)
 | 
						|
      {
 | 
						|
        for (int i = last; i < offs; i++)
 | 
						|
          {
 | 
						|
            cp = text.codePointAt(i);
 | 
						|
 | 
						|
            // Return the last found bound if there is a letter at the current
 | 
						|
            // location or is not whitespace (meaning it is a number or
 | 
						|
            // punctuation). The first case means that 'last' denotes the
 | 
						|
            // beginning of a word while the second case means it is the start
 | 
						|
            // of some else.
 | 
						|
            if (Character.isLetter(cp)
 | 
						|
                || !Character.isWhitespace(cp))
 | 
						|
              return last;
 | 
						|
          }
 | 
						|
        last = current;
 | 
						|
        current = wb.previous();
 | 
						|
      }
 | 
						|
 | 
						|
    return 0;
 | 
						|
  }
 | 
						|
 | 
						|
  /**
 | 
						|
   * Finds the start of a word for the given location.
 | 
						|
   * @param c the text component
 | 
						|
   * @param offs the offset location
 | 
						|
   * @return the location of the word beginning
 | 
						|
   * @throws BadLocationException if the offset location is invalid
 | 
						|
   */
 | 
						|
  public static final int getWordStart(JTextComponent c, int offs)
 | 
						|
      throws BadLocationException
 | 
						|
  {
 | 
						|
    String text = c.getText();
 | 
						|
 | 
						|
    if (offs < 0 || offs > text.length())
 | 
						|
      throw new BadLocationException("invalid offset specified", offs);
 | 
						|
 | 
						|
    BreakIterator wb = BreakIterator.getWordInstance();
 | 
						|
    wb.setText(text);
 | 
						|
 | 
						|
    if (wb.isBoundary(offs))
 | 
						|
      return offs;
 | 
						|
 | 
						|
    return wb.preceding(offs);
 | 
						|
  }
 | 
						|
 | 
						|
  /**
 | 
						|
   * Finds the end of a word for the given location.
 | 
						|
   * @param c the text component
 | 
						|
   * @param offs the offset location
 | 
						|
   * @return the location of the word end
 | 
						|
   * @throws BadLocationException if the offset location is invalid
 | 
						|
   */
 | 
						|
  public static final int getWordEnd(JTextComponent c, int offs)
 | 
						|
      throws BadLocationException
 | 
						|
  {
 | 
						|
    if (offs < 0 || offs >= c.getText().length())
 | 
						|
      throw new BadLocationException("invalid offset specified", offs);
 | 
						|
 | 
						|
    String text = c.getText();
 | 
						|
    BreakIterator wb = BreakIterator.getWordInstance();
 | 
						|
    wb.setText(text);
 | 
						|
    return wb.following(offs);
 | 
						|
  }
 | 
						|
 | 
						|
  /**
 | 
						|
   * Get the model position of the end of the row that contains the
 | 
						|
   * specified model position.  Return null if the given JTextComponent
 | 
						|
   * does not have a size.
 | 
						|
   * @param c the JTextComponent
 | 
						|
   * @param offs the model position
 | 
						|
   * @return the model position of the end of the row containing the given
 | 
						|
   * offset
 | 
						|
   * @throws BadLocationException if the offset is invalid
 | 
						|
   */
 | 
						|
  public static final int getRowEnd(JTextComponent c, int offs)
 | 
						|
      throws BadLocationException
 | 
						|
  {
 | 
						|
    String text = c.getText();
 | 
						|
    if (text == null)
 | 
						|
      return -1;
 | 
						|
 | 
						|
    // Do a binary search for the smallest position X > offs
 | 
						|
    // such that that character at positino X is not on the same
 | 
						|
    // line as the character at position offs
 | 
						|
    int high = offs + ((text.length() - 1 - offs) / 2);
 | 
						|
    int low = offs;
 | 
						|
    int oldHigh = text.length() + 1;
 | 
						|
    while (true)
 | 
						|
      {
 | 
						|
        if (c.modelToView(high).y != c.modelToView(offs).y)
 | 
						|
          {
 | 
						|
            oldHigh = high;
 | 
						|
            high = low + ((high + 1 - low) / 2);
 | 
						|
            if (oldHigh == high)
 | 
						|
              return high - 1;
 | 
						|
          }
 | 
						|
        else
 | 
						|
          {
 | 
						|
            low = high;
 | 
						|
            high += ((oldHigh - high) / 2);
 | 
						|
            if (low == high)
 | 
						|
              return low;
 | 
						|
          }
 | 
						|
      }
 | 
						|
  }
 | 
						|
 | 
						|
  /**
 | 
						|
   * Get the model position of the start of the row that contains the specified
 | 
						|
   * model position. Return null if the given JTextComponent does not have a
 | 
						|
   * size.
 | 
						|
   *
 | 
						|
   * @param c the JTextComponent
 | 
						|
   * @param offs the model position
 | 
						|
   * @return the model position of the start of the row containing the given
 | 
						|
   *         offset
 | 
						|
   * @throws BadLocationException if the offset is invalid
 | 
						|
   */
 | 
						|
  public static final int getRowStart(JTextComponent c, int offs)
 | 
						|
      throws BadLocationException
 | 
						|
  {
 | 
						|
    String text = c.getText();
 | 
						|
    if (text == null)
 | 
						|
      return -1;
 | 
						|
 | 
						|
    // Do a binary search for the greatest position X < offs
 | 
						|
    // such that the character at position X is not on the same
 | 
						|
    // row as the character at position offs
 | 
						|
    int high = offs;
 | 
						|
    int low = 0;
 | 
						|
    int oldLow = 0;
 | 
						|
    while (true)
 | 
						|
      {
 | 
						|
        if (c.modelToView(low).y != c.modelToView(offs).y)
 | 
						|
          {
 | 
						|
            oldLow = low;
 | 
						|
            low = high - ((high + 1 - low) / 2);
 | 
						|
            if (oldLow == low)
 | 
						|
              return low + 1;
 | 
						|
          }
 | 
						|
        else
 | 
						|
          {
 | 
						|
            high = low;
 | 
						|
            low -= ((low - oldLow) / 2);
 | 
						|
            if (low == high)
 | 
						|
              return low;
 | 
						|
          }
 | 
						|
      }
 | 
						|
  }
 | 
						|
 | 
						|
  /**
 | 
						|
   * Determine where to break the text in the given Segment, attempting to find
 | 
						|
   * a word boundary.
 | 
						|
   * @param s the Segment that holds the text
 | 
						|
   * @param metrics the font metrics used for calculating the break point
 | 
						|
   * @param x0 starting view location representing the start of the text
 | 
						|
   * @param x the target view location
 | 
						|
   * @param e the TabExpander used for expanding tabs (if this is null tabs
 | 
						|
   * are expanded to 1 space)
 | 
						|
   * @param startOffset the offset in the Document of the start of the text
 | 
						|
   * @return the offset at which we should break the text
 | 
						|
   */
 | 
						|
  public static final int getBreakLocation(Segment s, FontMetrics metrics,
 | 
						|
                                           int x0, int x, TabExpander e,
 | 
						|
                                           int startOffset)
 | 
						|
  {
 | 
						|
    int mark = Utilities.getTabbedTextOffset(s, metrics, x0, x, e, startOffset,
 | 
						|
                                             false);
 | 
						|
    int breakLoc = mark;
 | 
						|
    // If mark is equal to the end of the string, just use that position.
 | 
						|
    if (mark < s.count - 1)
 | 
						|
      {
 | 
						|
        for (int i = s.offset + mark; i >= s.offset; i--)
 | 
						|
          {
 | 
						|
            char ch = s.array[i];
 | 
						|
            if (ch < 256)
 | 
						|
              {
 | 
						|
                // For ASCII simply scan backwards for whitespace.
 | 
						|
                if (Character.isWhitespace(ch))
 | 
						|
                  {
 | 
						|
                    breakLoc = i - s.offset + 1;
 | 
						|
                    break;
 | 
						|
                  }
 | 
						|
              }
 | 
						|
            else
 | 
						|
              {
 | 
						|
                // Only query BreakIterator for complex chars.
 | 
						|
                BreakIterator bi = BreakIterator.getLineInstance();
 | 
						|
                bi.setText(s);
 | 
						|
                int pos = bi.preceding(i + 1);
 | 
						|
                if (pos > s.offset)
 | 
						|
                  {
 | 
						|
                    breakLoc = breakLoc - s.offset;
 | 
						|
                  }
 | 
						|
                break;
 | 
						|
              }
 | 
						|
          }
 | 
						|
      }
 | 
						|
    return breakLoc;
 | 
						|
  }
 | 
						|
 | 
						|
  /**
 | 
						|
   * Returns the paragraph element in the text component <code>c</code> at
 | 
						|
   * the specified location <code>offset</code>.
 | 
						|
   *
 | 
						|
   * @param c the text component
 | 
						|
   * @param offset the offset of the paragraph element to return
 | 
						|
   *
 | 
						|
   * @return the paragraph element at <code>offset</code>
 | 
						|
   */
 | 
						|
  public static final Element getParagraphElement(JTextComponent c, int offset)
 | 
						|
  {
 | 
						|
    Document doc = c.getDocument();
 | 
						|
    Element par = null;
 | 
						|
    if (doc instanceof StyledDocument)
 | 
						|
      {
 | 
						|
        StyledDocument styledDoc = (StyledDocument) doc;
 | 
						|
        par = styledDoc.getParagraphElement(offset);
 | 
						|
      }
 | 
						|
    else
 | 
						|
      {
 | 
						|
        Element root = c.getDocument().getDefaultRootElement();
 | 
						|
        int parIndex = root.getElementIndex(offset);
 | 
						|
        par = root.getElement(parIndex);
 | 
						|
      }
 | 
						|
    return par;
 | 
						|
  }
 | 
						|
 | 
						|
  /**
 | 
						|
   * Returns the document position that is closest above to the specified x
 | 
						|
   * coordinate in the row containing <code>offset</code>.
 | 
						|
   *
 | 
						|
   * @param c the text component
 | 
						|
   * @param offset the offset
 | 
						|
   * @param x the x coordinate
 | 
						|
   *
 | 
						|
   * @return  the document position that is closest above to the specified x
 | 
						|
   *          coordinate in the row containing <code>offset</code>
 | 
						|
   *
 | 
						|
   * @throws BadLocationException if <code>offset</code> is not a valid offset
 | 
						|
   */
 | 
						|
  public static final int getPositionAbove(JTextComponent c, int offset, int x)
 | 
						|
    throws BadLocationException
 | 
						|
  {
 | 
						|
    int offs = getRowStart(c, offset);
 | 
						|
 | 
						|
    if(offs == -1)
 | 
						|
      return -1;
 | 
						|
 | 
						|
    // Effectively calculates the y value of the previous line.
 | 
						|
    Point pt = c.modelToView(offs-1).getLocation();
 | 
						|
 | 
						|
    pt.x = x;
 | 
						|
 | 
						|
    // Calculate a simple fitting offset.
 | 
						|
    offs = c.viewToModel(pt);
 | 
						|
 | 
						|
    // Find out the real x positions of the calculated character and its
 | 
						|
    // neighbour.
 | 
						|
    int offsX = c.modelToView(offs).getLocation().x;
 | 
						|
    int offsXNext = c.modelToView(offs+1).getLocation().x;
 | 
						|
 | 
						|
    // Chose the one which is nearer to us and return its offset.
 | 
						|
    if (Math.abs(offsX-x) <= Math.abs(offsXNext-x))
 | 
						|
      return offs;
 | 
						|
    else
 | 
						|
      return offs+1;
 | 
						|
  }
 | 
						|
 | 
						|
  /**
 | 
						|
   * Returns the document position that is closest below to the specified x
 | 
						|
   * coordinate in the row containing <code>offset</code>.
 | 
						|
   *
 | 
						|
   * @param c the text component
 | 
						|
   * @param offset the offset
 | 
						|
   * @param x the x coordinate
 | 
						|
   *
 | 
						|
   * @return  the document position that is closest above to the specified x
 | 
						|
   *          coordinate in the row containing <code>offset</code>
 | 
						|
   *
 | 
						|
   * @throws BadLocationException if <code>offset</code> is not a valid offset
 | 
						|
   */
 | 
						|
  public static final int getPositionBelow(JTextComponent c, int offset, int x)
 | 
						|
    throws BadLocationException
 | 
						|
  {
 | 
						|
    int offs = getRowEnd(c, offset);
 | 
						|
 | 
						|
    if(offs == -1)
 | 
						|
      return -1;
 | 
						|
 | 
						|
    Point pt = null;
 | 
						|
 | 
						|
    // Note: Some views represent the position after the last
 | 
						|
    // typed character others do not. Converting offset 3 in "a\nb"
 | 
						|
    // in a PlainView will return a valid rectangle while in a
 | 
						|
    // WrappedPlainView this will throw a BadLocationException.
 | 
						|
    // This behavior has been observed in the RI.
 | 
						|
    try
 | 
						|
      {
 | 
						|
        // Effectively calculates the y value of the next line.
 | 
						|
        pt = c.modelToView(offs+1).getLocation();
 | 
						|
      }
 | 
						|
    catch(BadLocationException ble)
 | 
						|
      {
 | 
						|
        return offset;
 | 
						|
      }
 | 
						|
 | 
						|
    pt.x = x;
 | 
						|
 | 
						|
    // Calculate a simple fitting offset.
 | 
						|
    offs = c.viewToModel(pt);
 | 
						|
 | 
						|
    if (offs == c.getDocument().getLength())
 | 
						|
      return offs;
 | 
						|
 | 
						|
    // Find out the real x positions of the calculated character and its
 | 
						|
    // neighbour.
 | 
						|
    int offsX = c.modelToView(offs).getLocation().x;
 | 
						|
    int offsXNext = c.modelToView(offs+1).getLocation().x;
 | 
						|
 | 
						|
    // Chose the one which is nearer to us and return its offset.
 | 
						|
    if (Math.abs(offsX-x) <= Math.abs(offsXNext-x))
 | 
						|
      return offs;
 | 
						|
    else
 | 
						|
      return offs+1;
 | 
						|
    }
 | 
						|
 | 
						|
  /** This is an internal helper method which is used by the
 | 
						|
   * <code>javax.swing.text</code> package. It simply delegates the
 | 
						|
   * call to a method with the same name on the <code>NavigationFilter</code>
 | 
						|
   * of the provided <code>JTextComponent</code> (if it has one) or its UI.
 | 
						|
   *
 | 
						|
   * If the underlying method throws a <code>BadLocationException</code> it
 | 
						|
   * will be swallowed and the initial offset is returned.
 | 
						|
   */
 | 
						|
  static int getNextVisualPositionFrom(JTextComponent t, int offset, int direction)
 | 
						|
  {
 | 
						|
    NavigationFilter nf = t.getNavigationFilter();
 | 
						|
 | 
						|
    try
 | 
						|
      {
 | 
						|
        return (nf != null)
 | 
						|
          ? nf.getNextVisualPositionFrom(t,
 | 
						|
                                         offset,
 | 
						|
                                         Bias.Forward,
 | 
						|
                                         direction,
 | 
						|
                                         new Position.Bias[1])
 | 
						|
          : t.getUI().getNextVisualPositionFrom(t,
 | 
						|
                                                offset,
 | 
						|
                                                Bias.Forward,
 | 
						|
                                                direction,
 | 
						|
                                                new Position.Bias[1]);
 | 
						|
      }
 | 
						|
    catch (BadLocationException ble)
 | 
						|
    {
 | 
						|
      return offset;
 | 
						|
    }
 | 
						|
 | 
						|
  }
 | 
						|
 | 
						|
}
 |