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/*
 *
 * (C) Copyright IBM Corp. 1998-2003 All Rights Reserved
 */

package sun.font;

import java.awt.Font;

import java.awt.font.FontRenderContext;
import java.text.Bidi;

  
A factory for text labels.  Basically this just holds onto the stuff that
doesn't change-- the render context, context, and bidi info for the context-- and gets
called for each subrange you want to create.

See Also:
/**
   * A factory for text labels.  Basically this just holds onto the stuff that
   * doesn't change-- the render context, context, and bidi info for the context-- and gets
   * called for each subrange you want to create.
   *
   * @see Font
   * @see FontRenderContext
   * @see java.awt.font.GlyphVector
   * @see TextLabel
   * @see ExtendedTextLabel
   * @see Bidi
   * @see java.awt.font.TextLayout
   */

public final class TextLabelFactory {
  private final FontRenderContext frc;
  private final char[] text;
  private final Bidi bidi;
  private Bidi lineBidi;
  private final int flags;
  private int lineStart;
  private int lineLimit;

  
Initialize a factory to produce glyph arrays.

Params:
  • frc – the FontRenderContext to use for the arrays to be produced.
  • text – the text of the paragraph.
  • bidi – the bidi information for the paragraph text, or null if the
entire text is left-to-right text.
/**
   * Initialize a factory to produce glyph arrays.
   * @param frc the FontRenderContext to use for the arrays to be produced.
   * @param text the text of the paragraph.
   * @param bidi the bidi information for the paragraph text, or null if the
   * entire text is left-to-right text.
   */
  public TextLabelFactory(FontRenderContext frc,
                          char[] text,
                          Bidi bidi,
                          int flags) {
    this.frc = frc;
    this.text = text.clone();
    this.bidi = bidi;
    this.flags = flags;
    this.lineBidi = bidi;
    this.lineStart = 0;
    this.lineLimit = text.length;
  }

  public FontRenderContext getFontRenderContext() {
    return frc;
  }

  public Bidi getLineBidi() {
    return lineBidi;
  }

  
Set a line context for the factory.  Shaping only occurs on this line.
Characters are ordered as they would appear on this line.

Params:
  • lineStart – the index within the text of the start of the line.
  • lineLimit – the index within the text of the limit of the line.
/**
   * Set a line context for the factory.  Shaping only occurs on this line.
   * Characters are ordered as they would appear on this line.
   * @param lineStart the index within the text of the start of the line.
   * @param lineLimit the index within the text of the limit of the line.
   */
  public void setLineContext(int lineStart, int lineLimit) {
    this.lineStart = lineStart;
    this.lineLimit = lineLimit;
    if (bidi != null) {
      lineBidi = bidi.createLineBidi(lineStart, lineLimit);
    }
  }

  
Create an extended glyph array for the text between start and limit.

Params:
  • font – the font to use to generate glyphs and character positions.
  • start – the start of the subrange for which to create the glyph array
  • limit – the limit of the subrange for which to create glyph array
Start and limit must be within the bounds of the current line.  If no
line context has been set, the entire text is used as the current line.
The text between start and limit will be treated as though it all has
the same bidi level (and thus the same directionality) as the character
at start.  Clients should ensure that all text between start and limit
has the same bidi level for the current line.
/**
   * Create an extended glyph array for the text between start and limit.
   *
   * @param font the font to use to generate glyphs and character positions.
   * @param start the start of the subrange for which to create the glyph array
   * @param limit the limit of the subrange for which to create glyph array
   *
   * Start and limit must be within the bounds of the current line.  If no
   * line context has been set, the entire text is used as the current line.
   * The text between start and limit will be treated as though it all has
   * the same bidi level (and thus the same directionality) as the character
   * at start.  Clients should ensure that all text between start and limit
   * has the same bidi level for the current line.
   */
  public ExtendedTextLabel createExtended(Font font,
                                          CoreMetrics lm,
                                          Decoration decorator,
                                          int start,
                                          int limit) {

    if (start >= limit || start < lineStart || limit > lineLimit) {
      throw new IllegalArgumentException("bad start: " + start + " or limit: " + limit);
    }

    int level = lineBidi == null ? 0 : lineBidi.getLevelAt(start - lineStart);
    int linedir = (lineBidi == null || lineBidi.baseIsLeftToRight()) ? 0 : 1;
    int layoutFlags = flags & ~0x9; // remove bidi, line direction flags
    if ((level & 0x1) != 0) layoutFlags |= 1; // rtl
    if ((linedir & 0x1) != 0) layoutFlags |= 8; // line rtl

    TextSource source = new StandardTextSource(text, start, limit - start, lineStart, lineLimit - lineStart, level, layoutFlags, font, frc, lm);
    return new ExtendedTextSourceLabel(source, decorator);
  }

  
Create a simple glyph array for the text between start and limit.

Params:
  • font – the font to use to generate glyphs and character positions.
  • start – the start of the subrange for which to create the glyph array
  • limit – the limit of the subrange for which to create glyph array
/**
   * Create a simple glyph array for the text between start and limit.
   *
   * @param font the font to use to generate glyphs and character positions.
   * @param start the start of the subrange for which to create the glyph array
   * @param limit the limit of the subrange for which to create glyph array
   */
  public TextLabel createSimple(Font font,
                                CoreMetrics lm,
                                int start,
                                int limit) {

    if (start >= limit || start < lineStart || limit > lineLimit) {
      throw new IllegalArgumentException("bad start: " + start + " or limit: " + limit);
    }

    int level = lineBidi == null ? 0 : lineBidi.getLevelAt(start - lineStart);
    int linedir = (lineBidi == null || lineBidi.baseIsLeftToRight()) ? 0 : 1;
    int layoutFlags = flags & ~0x9; // remove bidi, line direction flags
    if ((level & 0x1) != 0) layoutFlags |= 1; // rtl
    if ((linedir & 0x1) != 0) layoutFlags |= 8; // line rtl
    TextSource source = new StandardTextSource(text, start, limit - start, lineStart, lineLimit - lineStart, level, layoutFlags, font, frc, lm);
    return new TextSourceLabel(source);
  }
}