Rumah > Soal Jawab > teks badan
public abstract class Rhythm {
/**
* @return duration between {@linkplain Note} in milliseconds
*/
public abstract long getDuration();
public void perform() {
long duration = getDuration();
try {
Thread.sleep(duration);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
throw new RuntimeException(ie);
}
}
}
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@Override public void play(Rhythm rhythm, Note note, NoteCallback noteCallback){
rhythm.getDuration();//想在这里重写getDuration方法,如何做到?
rhythm.perform();
note.getNoteValue();
noteCallback.notePlayed(note);
}
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//重写成如下形式
@Override public long getDuration(){
return (expectedMs);
}
代码附上。在play() 方法中如何直接重写Rhythm类中的抽象方法getDuration()呢? 创建rhythm对象是可以用匿名类的方法实例化的,那是实例化之后 想调用一个重写的getDuration()方法,有什么办法么?在不引入子类继承的前提下。
怪我咯2017-04-18 10:49:54
Java tidak boleh melakukan ini, tetapi ia boleh menggunakan kelas dalaman untuk mencapai keperluan ini secara berselindung
public abstract class Rhythm {
/**
* @return duration between {@linkplain Note} in milliseconds
*/
public abstract long getDuration();
public abstract class InnderClass {
public abstract long getDuration();
}
private InnderClass innderClass;
public Rhythm() {
innderClass = new InnderClass() {
@Override
public long getDuration() {
return Rhythm.this.getDuration();
}
};
}
public void setInnderClass(InnderClass innderClass) {
this.innderClass = innderClass;
}
public void perform() {
long duration = innderClass.getDuration();
try {
Thread.sleep(duration);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
throw new RuntimeException(ie);
}
}
}
@Override public void play(Rhythm rhythm, Note note, NoteCallback noteCallback){
//rhythm.getDuration();//想在这里重写getDuration方法,如何做到?
rhythm.setInnderClass(rhythm.new InnderClass() {
@Override
public long getDuration() {
// TODO 把实现放到这里
return 0;
}
});
rhythm.perform();
note.getNoteValue();
noteCallback.notePlayed(note);
}