public class Test {public static void main(String[] args) {Book bookA = new Book("JAVA",79.8);Book bookB = (Book) bookA.clone();}}請問我在輸出克隆對象時，向下轉型時紅色的字條報錯了，說要加上throws ecception是為什么呢？剛學java不久小白一枚，希望各位老哥幫忙解答一下