Program: 66866
Project: 66866
Buggy source:
@Override public void drawArc(ArcRenderEvent are) throws ChartException {
  if (iv != null) {
    iv.modifyEvent(are);
  }
  final LineAttributes lia=are.getOutline();
  if (!validateLineAttributes(are.getSource(),lia)) {
    return;
  }
  final Color cFG=(Color)validateEdgeColor(lia.getColor(),are.getBackground(),_ids);
  if (cFG == null || cFG.getAlpha() == 0) {
    return;
  }
  Stroke sPrevious=null;
  Stroke sCurrent=getCachedStroke(lia);
  if (sCurrent != null) {
    sPrevious=_g2d.getStroke();
    _g2d.setStroke(sCurrent);
  }
  _g2d.setColor(cFG);
  if (are.getInnerRadius() >= 0 && are.getOuterRadius() > 0 && are.getInnerRadius() < are.getOuterRadius()) {
    Bounds rctOuter=BoundsImpl.create(are.getTopLeft().getX() + (are.getWidth() - 2 * are.getOuterRadius()) / 2,are.getTopLeft().getY() + (are.getHeight() - 2 * are.getOuterRadius()) / 2,2 * are.getOuterRadius(),2 * are.getOuterRadius());
    Bounds rctInner=BoundsImpl.create(are.getTopLeft().getX() + (are.getWidth() - 2 * are.getInnerRadius()) / 2,are.getTopLeft().getY() + (are.getHeight() - 2 * are.getInnerRadius()) / 2,2 * are.getInnerRadius(),2 * are.getInnerRadius());
    Shape outerArc=new Arc2D.Double(rctOuter.getLeft(),rctOuter.getTop(),rctOuter.getWidth(),rctOuter.getHeight(),are.getStartAngle(),are.getAngleExtent(),Arc2D.OPEN);
    Shape innerArc=new Arc2D.Double(rctInner.getLeft(),rctInner.getTop(),rctInner.getWidth(),rctInner.getHeight(),are.getStartAngle() + are.getAngleExtent(),-are.getAngleExtent(),Arc2D.OPEN);
    double startAngle=Math.toRadians(-are.getStartAngle());
    double stopAngle=Math.toRadians(-are.getStartAngle() - are.getAngleExtent());
    double xsOuter=(rctOuter.getLeft() + (Math.cos(startAngle) * 0.5 + 0.5) * rctOuter.getWidth());
    double ysOuter=(rctOuter.getTop() + (Math.sin(startAngle) * 0.5 + 0.5) * rctOuter.getHeight());
    double xeInner=(rctInner.getLeft() + (Math.cos(stopAngle) * 0.5 + 0.5) * rctInner.getWidth());
    double yeInner=(rctInner.getTop() + (Math.sin(stopAngle) * 0.5 + 0.5) * rctInner.getHeight());
    GeneralPath gp=new GeneralPath();
    gp.append(outerArc,false);
    gp.lineTo((float)xeInner,(float)yeInner);
    gp.append(innerArc,false);
    gp.lineTo((float)xsOuter,(float)ysOuter);
    Area area=new Area(gp);
    Shape prevClip=_g2d.getClip();
    Area ar2=new Area(area);
    if (prevClip != null) {
      Area ar1=new Area(prevClip);
      ar2.intersect(ar1);
    }
    _g2d.setClip(ar2);
    _g2d.draw(area);
    _g2d.setClip(prevClip);
  }
 else {
    _g2d.draw(new Arc2D.Double(are.getTopLeft().getX(),are.getTopLeft().getY(),are.getWidth(),are.getHeight(),are.getStartAngle(),are.getAngleExtent(),toG2dArcType(are.getStyle())));
  }
  if (sPrevious != null) {
    _g2d.setStroke(sPrevious);
  }
}

Fixed version (ground truth):
@Override public void drawArc(ArcRenderEvent are) throws ChartException {
  if (iv != null) {
    iv.modifyEvent(are);
  }
  final LineAttributes lia=are.getOutline();
  if (!validateLineAttributes(are.getSource(),lia)) {
    return;
  }
  final Color cFG=(Color)validateEdgeColor(lia.getColor(),are.getBackground(),_ids);
  if (cFG == null || cFG.getAlpha() == 0) {
    return;
  }
  Stroke sPrevious=null;
  Stroke sCurrent=getCachedStroke(lia);
  if (sCurrent != null) {
    sPrevious=_g2d.getStroke();
    _g2d.setStroke(sCurrent);
  }
  _g2d.setColor(cFG);
  if ((are.getInnerRadius() >= 0 && are.getOuterRadius() > 0 && are.getInnerRadius() < are.getOuterRadius()) || (are.getInnerRadius() > 0 && are.getOuterRadius() <= 0)) {
    Bounds rctOuter, rctInner;
    if (are.getOuterRadius() > 0) {
      rctOuter=BoundsImpl.create(are.getTopLeft().getX() + (are.getWidth() - 2 * are.getOuterRadius()) / 2,are.getTopLeft().getY() + (are.getHeight() - 2 * are.getOuterRadius()) / 2,2 * are.getOuterRadius(),2 * are.getOuterRadius());
    }
 else {
      rctOuter=BoundsImpl.create(are.getTopLeft().getX(),are.getTopLeft().getY(),are.getWidth(),are.getHeight());
    }
    rctInner=BoundsImpl.create(are.getTopLeft().getX() + (are.getWidth() - 2 * are.getInnerRadius()) / 2,are.getTopLeft().getY() + (are.getHeight() - 2 * are.getInnerRadius()) / 2,2 * are.getInnerRadius(),2 * are.getInnerRadius());
    Shape outerArc=new Arc2D.Double(rctOuter.getLeft(),rctOuter.getTop(),rctOuter.getWidth(),rctOuter.getHeight(),are.getStartAngle(),are.getAngleExtent(),Arc2D.OPEN);
    Shape innerArc=new Arc2D.Double(rctInner.getLeft(),rctInner.getTop(),rctInner.getWidth(),rctInner.getHeight(),are.getStartAngle() + are.getAngleExtent(),-are.getAngleExtent(),Arc2D.OPEN);
    double startAngle=Math.toRadians(-are.getStartAngle());
    double stopAngle=Math.toRadians(-are.getStartAngle() - are.getAngleExtent());
    double xsOuter=(rctOuter.getLeft() + (Math.cos(startAngle) * 0.5 + 0.5) * rctOuter.getWidth());
    double ysOuter=(rctOuter.getTop() + (Math.sin(startAngle) * 0.5 + 0.5) * rctOuter.getHeight());
    double xeInner=(rctInner.getLeft() + (Math.cos(stopAngle) * 0.5 + 0.5) * rctInner.getWidth());
    double yeInner=(rctInner.getTop() + (Math.sin(stopAngle) * 0.5 + 0.5) * rctInner.getHeight());
    GeneralPath gp=new GeneralPath();
    gp.append(outerArc,false);
    gp.lineTo((float)xeInner,(float)yeInner);
    gp.append(innerArc,false);
    gp.lineTo((float)xsOuter,(float)ysOuter);
    Area area=new Area(gp);
    Shape prevClip=_g2d.getClip();
    Area ar2=new Area(area);
    if (prevClip != null) {
      Area ar1=new Area(prevClip);
      ar2.intersect(ar1);
    }
    _g2d.setClip(ar2);
    _g2d.draw(area);
    _g2d.setClip(prevClip);
  }
 else {
    _g2d.draw(new Arc2D.Double(are.getTopLeft().getX(),are.getTopLeft().getY(),are.getWidth(),are.getHeight(),are.getStartAngle(),are.getAngleExtent(),toG2dArcType(are.getStyle())));
  }
  if (sPrevious != null) {
    _g2d.setStroke(sPrevious);
  }
}