Java 工厂模式

一、抽象接口->Printer.java

public interface Printer {
public void open();

public void close();

public void print(String s);

}

二、实现接口的类1->HPPrinter.java

public class HPPrinter implements Printer {

@Override
public void open() {
System.out.println("HPPrinter open");
}

@Override
public void close() {
System.out.println("HPPrinter close");
}

@Override
public void print(String s) {
System.out.println("HPPrinter print----->"+s);
}

}

三、实现接口的类2->CannonPrinter .java

public class CannonPrinter implements Printer {

@Override
public void open() {
System.out.println("CannonPrinter open");
}

@Override
public void close() {
System.out.println("CannonPrinter close");
}

@Override
public void print(String s) {
System.out.println("CannonPrinter print----->"+s);
}

}

四、产生priter的工厂类->PrinterFactory .java

public class PrinterFactory {

//根据用户的输入new 相应类型的打印机，及向上转型为Printer
//getPriner方法声明为static，则不用生成对象可用"类名.方法名"直接调用
public static Printer getPrinter(int flag) {
Printer printer = null;
if(flag == 0){
printer = new HPPrinter();
}else if(flag == 1){
printer = new CannonPrinter();
}
return printer;
}

}

五、测试代码->Test.java

public class Test {
public static void main(String [] args){
Printer printer = null;
int flag = 0;
printer = PrinterFactory.getPrinter(flag);
printer.open();
printer.print("test");
printer.close();
}

}

ps:参考mars老师的视频，谢谢mars老师