import java.awt.geom.*;
import java.awt.image.*;
private static final Color clrHi = new Color(255, 229, 63);
private static final Color clrLo = new Color(255, 105, 0);
private static final Color clrGlowInnerHi = new Color(253, 239, 175, 148);
private static final Color clrGlowInnerLo = new Color(255, 209, 0);
private static final Color clrGlowOuterHi = new Color(253, 239, 175, 124);
private static final Color clrGlowOuterLo = new Color(255, 179, 0);
private Shape createClipShape() {
　float border = 20.0f;
　float x1 = border;
　float y1 = border;
　float x2 = width - border;
　float y2 = height - border;
　float adj = 3.0f; //幫助圓化類銳的拐角
　float arc = 8.0f;
　float dcx = 0.18f * width;
　float cx1 = x1-dcx;
　float cy1 = 0.40f * height;
　float cx2 = x1+dcx;
　float cy2 = 0.50f * height;
　GeneralPath gp = new GeneralPath();
　gp.moveTo(x1-adj, y1+adj);
　gp.quadTo(x1, y1, x1+adj, y1);
　gp.lineTo(x2-arc, y1);
　gp.quadTo(x2, y1, x2, y1+arc);
　gp.lineTo(x2, y2-arc);
　gp.quadTo(x2, y2, x2-arc, y2);
　gp.lineTo(x1+adj, y2);
　gp.quadTo(x1, y2, x1, y2-adj);
　gp.curveTo(cx2, cy2, cx1, cy1, x1-adj, y1+adj);
　gp.closePath();
　return gp;
}
private BufferedImage createClipImage(Shape s) {
　// 建立一半透明的中間影象，我們可以使用它來實現軟修剪效果
　GraphicsConfiguration gc = g.getDeviceConfiguration();
　BufferedImage img = gc.createCompatibleImage(width, height, Transparency.TRANSLUCENT);
　Graphics2D g2 = img.createGraphics();
　//清除影象，這樣所有的畫素都具有零alpha
　g2.setComposite(AlphaComposite.Clear);
　g2.fillRect(0, 0, width, height);
　// 把我們的修剪形狀生成到影象上。注意，我們啟動了
　// 反走樣功能以實現軟修剪效果。你可以
　//嘗試註釋掉啟動反走樣的這一行，那麼
　//你會看到通常的生硬的修剪效果.
　g2.setComposite(AlphaComposite.Src);
　g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
　g2.setColor(Color.WHITE);
　g2.fill(s);
　g2.dispose();
　return img;
}
private static Color getMixedColor(Color c1, float pct1, Color c2, float pct2) {
　float[] clr1 = c1.getComponents(null);
　float[] clr2 = c2.getComponents(null);
　for (int i = 0; i < clr1.length; i++) {
　　clr1[i] = (clr1[i] * pct1) + (clr2[i] * pct2);
　}
　return new Color(clr1[0], clr1[1], clr1[2], clr1[3]);
}
//下面是實現技巧：為了實現發光效果，我們開始使用一種"內部"顏色粗筆
//和筆劃需要的形狀。然後，我們不斷地把筆變細，
//並且不斷地移向"外部"顏色，
//並且不斷地提高顏色的不透明度以便使其朝向形狀的內部看上去暗淡。
//我們使用已經生成到我們的目的影象上的"修剪形狀"，這樣以來，
//SRC_ATOP規則就會修剪在我們的形狀外部的筆劃部分。
private void paintBorderGlow(Graphics2D g2, int glowWidth) {
　int gw = glowWidth*2;
　for (int i=gw; i >= 2; i-=2) {
　　float pct = (float)(gw - i) / (gw - 1);
　　Color mixHi = getMixedColor(clrGlowInnerHi, pct,clrGlowOuterHi, 1.0f - pct);
　　Color mixLo = getMixedColor(clrGlowInnerLo, pct,clrGlowOuterLo, 1.0f - pct);
　　g2.setPaint(new GradientPaint(0.0f, height*0.25f, mixHi,0.0f, height, mixLo));
　　//g2.setColor(Color.WHITE);
　　g2.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, pct));
　　g2.setStroke(new BasicStroke(i));
　　g2.draw(clipShape);
　}
}
Shape clipShape = createClipShape();
//Shape clipShape = new Ellipse2D.Float(width/4, height/4, width/2, height/2);
//把背景清除為白色
g.setColor(Color.WHITE);
g.fillRect(0, 0, width, height);
//設定修剪形狀
BufferedImage clipImage = createClipImage(clipShape);
Graphics2D g2 = clipImage.createGraphics();
//使用漸變填充形狀
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.setComposite(AlphaComposite.SrcAtop);
g2.setPaint(new GradientPaint(0, 0, clrHi, 0, height, clrLo));
g2.fill(clipShape);
//應用邊界發光效果
paintBorderGlow(g2, 8);
g2.dispose();
g.drawImage(clipImage, 0, 0, null);