下面列出了怎么用java.awt.PrintGraphics的API类实例代码及写法，或者点击链接到github查看源代码。
static boolean isPrinting(Graphics g) {
return (g instanceof PrinterGraphics || g instanceof PrintGraphics);
}
private static boolean isPrinting(Graphics g) {
return g instanceof PrintGraphics || g instanceof PrinterGraphics;
}