java - Swing paint issue -

i have custom scrollbarui paint both thumb , track of scrollbar. when scrolling keeps lines below don't want. :

painting code below:

protected void paintthumb(graphics g, jcomponent c, rectangle thumbbounds) {     graphics2d g2d = (graphics2d) g;      gradientpaint gradient = new gradientpaint(new point(thumbbounds.x, thumbbounds.y), gray, new          point(thumbbounds.x + width, thumbbounds.y), white);      g.setcolor(white);     g.fillroundrect(thumbbounds.x + 1, thumbbounds.y + 1, thumbbounds.width - 3, thumbbounds.height - 1, 2, 2);      g2d.setpaint(gradient);     g2d.fillroundrect(thumbbounds.x + 2, thumbbounds.y + 2, thumbbounds.width - 4, thumbbounds.height - 3, 3, 3);      //draw middle lines:     if ((getminimumthumbsize().height + 10) < thumbbounds.height) {         g.setcolor(new color(167, 167, 167));         int w = ((thumbbounds.width > 16) ? 8 : (int) ((thumbbounds.width / 2.0) + 0.5));         int x = (thumbbounds.width > 0) ? (thumbbounds.x + ((thumbbounds.width - w) / 2) - 1) : thumbbounds.x;          g.drawline(x, (thumbbounds.y + (thumbbounds.height / 2) - 3), (x + w), (thumbbounds.y + (thumbbounds.height / 2) - 3));         g.drawline(x, (thumbbounds.y + (thumbbounds.height / 2) - 1), (x + w), (thumbbounds.y + (thumbbounds.height / 2) - 1));         g.drawline(x, (thumbbounds.y + (thumbbounds.height / 2) + 1), (x + w), (thumbbounds.y + (thumbbounds.height / 2) + 1));     }      g.setcolor(color_1);     g.drawroundrect(thumbbounds.x, thumbbounds.y, thumbbounds.width - 2, thumbbounds.height, 2, 2); } 

you need use

g.drawroundrect(..., thumbbounds.height - 1, 2, 2)  

instead of

g.drawroundrect(..., thumbbounds.height, 2, 2) 

the bottom edges of drawroundrect(x,y,width,height,arcw,arch) @ y + height, bottom edges of repaint(thumbbounds) @ thumbbounds.y + thumbbounds.height - 1. 1px line remain free of repaint.