书上的课后题,我觉得有用就把放这里了

class NoThisSongException extends Exception { public NoThisSongException() { super(); } public NoThisSongException(String str) { super(str); } } class Player { public void play(int index) throws NoThisSongException{ if(index>10){ throw new NoThisSongException("您播放的歌曲不存在"); } else { System.out.println("歌曲"+index+"已经播放"); } } } public class test3 { public static void main(String[] args) { Player p1 = new Player(); try{ p1.play(5); p1.play(11); }catch(NoThisSongException e){ System.out.println(e.getMessage()); } } }