JLabelの文字列を折り返し

class WrappedLabel extends JLabel {
  private GlyphVector gvtext;
  private int width = -1;
  public WrappedLabel() {
    this(null);
  }

  public WrappedLabel(String str) {
    super(str);
  }

  @Override public void doLayout() {
    Insets i = getInsets();
    int w = getWidth() - i.left - i.right;
    if (w != width) {
      Font font = getFont();
      FontMetrics fm = getFontMetrics(font);
      FontRenderContext frc = fm.getFontRenderContext();
      gvtext = getWrappedGlyphVector(getText(), w, font, frc);
      width = w;
    }
    super.doLayout();
  }

  @Override protected void paintComponent(Graphics g) {
    if (gvtext == null) {
      super.paintComponent(g);
    } else {
      Insets i = getInsets();
      Graphics2D g2 = (Graphics2D) g.create();
      g2.setPaint(Color.RED);
      g2.drawGlyphVector(gvtext, i.left, getFont().getSize() + i.top);
      g2.dispose();
    }
  }

  private GlyphVector getWrappedGlyphVector(
      String str, float width, Font font, FontRenderContext frc) {
    Point2D gmPos = new Point2D.Double(0d, 0d);
    GlyphVector gv = font.createGlyphVector(frc, str);
    float lineheight = (float) (gv.getLogicalBounds().getHeight());
    float xpos = 0f;
    float advance = 0f;
    int lineCount = 0;
    GlyphMetrics gm;
    for (int i = 0; i < gv.getNumGlyphs(); i++) {
      gm = gv.getGlyphMetrics(i);
      advance = gm.getAdvance();
      if (xpos < width && width <= xpos + advance) {
        lineCount++;
        xpos = 0f;
      }
      gmPos.setLocation(xpos, lineheight * lineCount);
      gv.setGlyphPosition(i, gmPos);
      xpos = xpos + advance;
    }
    return gv;
  }
}