通过Iterator遍历set集合元素 遍历不出来
public void testIterator(){
Set<Course> set = new HashSet<Course>();
Iterator<Course> it = set.iterator();
System.out.println("通过Iterator遍历");
while(it.hasNext()){
// System.out.println(it.hasNext());
// System.out.println(".....");
System.out.println(it.next());
}
}
