interface Printer{publicvoid open();publicvoid close();publicvoid print(String s);}classHPPrinter implements Printer{publicvoid open(){System.out.println("HP open");}publicvoid close(){System.out.println("HP close");}publicvoid print(String s){System.out.println("HP print---->"+ s);}}classCanonPrinter implements Printer{privatevoid clean(){System.out.println("clean");}publicvoid close(){this.clean();System.out.println("Canon close");}publicvoid open(){System.out.println("Canon open");}publicvoid print(String s){System.out.println("Canon print---->"+ s);}}classPrinterFactory{publicstaticPrinter getPrinter(int flag){Printer printer = null;if(flag ==0){ printer =newHPPrinter();}elseif(flag ==1){ printer =newCanonPrinter();}return printer;}}classTest{publicstaticvoid main(String args []){//根据用户的选择，生成相应的打印机对象//并且向上转型为Printer类型//Printer getPrinter(int flag)int flag =0;Printer printer =PrinterFactory.getPrinter(flag); printer.open(); printer.print("test"); printer.close();}}原文：http://www.cnblogs.com/arroneve/p/5815458.html