public void test1(){
ArrayList<String> arraylist = new ArrayList<String>();
arraylist.add("a");
arraylist.add("a");
HashSet<String> sets = new HashSet<String>(arraylist);
System.out.println(setsd.size());
}
輸出結果爲:1
public void test1(){
ArrayList<String> arraylist = new ArrayList<String>();
arraylist.add("a");
arraylist.add("a");
HashSet<String> sets = new HashSet<String>(arraylist);
System.out.println(setsd.size());
}
輸出結果爲:1