①

根据数组创建ArrayList

String[] stringArray = { "a", "b", "c", "d", "e" };

ArrayList<String> arrayList = new ArrayList<String>(Arrays.asList(stringArray));

System.out.println(arrayList);// [a, b, c, d, e]

 

②

将ArrayList转换为数组

String[] stringArray = { "a", "b", "c", "d", "e" };

ArrayList<String> arrayList = new ArrayList<String>(Arrays.asList(stringArray));

String[] stringArr = new String[arrayList.size()];

arrayList.toArray(stringArr);

for (String s : stringArr){

   System.out.println(s);

}

③

将数组转换为Set

Set
      
        set = new HashSet
       
        (Arrays.asList(stringArray));
       
      

System.out.println(set);//[d, e, b, c, a]

 

④

 

 

⑤

 

 

⑥

 

 

⑦

 

 

⑧

 

 

⑨

 

 

⑩

 

 

⑪

 

 

⑫

 

 

⑬

 

 

⑭

 

 

⑮

 

 

⑯

 

 

⑰

 

 

⑱

 

 

⑲

 

 

⑳