我正在尝试创建一个简单的程序，将字符串发送到打印机进行打印。这是我的程序的样子:importjavax.print.Doc;importjavax.print.DocFlavor;importjavax.print.DocPrintJob;importjavax.print.PrintException;importjavax.print.PrintService;importjavax.print.PrintServiceLookup;importjavax.print.SimpleDoc;publicclassPrinterTest{publicstaticvoidmain(Str