2
A
回答
8
试试这个
abstract class Command {
final public void execute(){
run();
onComplete();
}
protected abstract void run();
protected abstract void onComplete();
}
//usage
abstract class HiCommand extends Command {
protected void run(){
System.out.println("Hi, ");
}
protected abstract void onComplete();
}
new HiCommand(){
@Override
protected void onComplete() {
System.out.println("world");
}
}.execute();
或本
interface WhenDone{
void onComplete();
}
abstract class Command {
private final WhenDone callback;
protected Command(WhenDone callback){
this.callback = callback;
}
final public void execute(){
run();
callback.onComplete();
}
protected abstract void run();
}
//usage
class PrintHi extends Command {
protected PrintHi(WhenDone callback){
super(callback);
}
protected void run(){
System.out.println("Hi, ");
}
}
class PrintWorld implements WhenDone {
public void onComplete(){
System.out.println("world!");
}
}
//somewhere
new PrintHi(new PrintWorld()).execute();
使用的例子是不是来自真实的生活。很可能,您应该通过创建CommandManager
将创建和调用执行分开。
+0
谢谢,斯塔斯!嗯...现在我必须弄清楚那个父回调命令是怎么样的。我不会否认你的意见。 :-) – Cambiata 2010-12-06 08:18:15
GoF命令模式不包括回调。请添加更多信息或显示您真正想到的模式的网址参考。 – 2010-12-06 08:06:01