java Set 遍历

//1.迭代遍历：

Set<String> set = new HashSet<String>();

Iterator<String> it = set.iterator();

while (it.hasNext()) {

  String str = it.next();

  System.out.println(str);

}

  

//2.for循环遍历：

for (String str : set) {

      System.out.println(str);

}

  

  

//优点还体现在泛型 假如 set中存放的是Object

  

Set<Object> set =new HashSet<Object>();

//for循环遍历：

for (Object obj: set) {

      if(objinstanceof Integer){

            intaa= (Integer)obj;

      }elseif(obj instanceofString){

            String aa = (String)obj

      }

            ........

}