数组、字符串、集合的相互转换
1.数组转字符串
public static void main(String[] args) { // 定义一个数组 char[] a = {'a','b','c','d'}; String b = new String(a); System.out.println(b);// abcd }
2.数组转集合
public static void main(String[] args) { // 定义一个数组 Integer[] a = {1,2,3,4}; List list = Arrays.asList(a); System.out.println(list);//[1,2,3,4] }
3.字符串转数组
public static void main(String[] args) { String str ="asdfg"; char[] a = str.toCharArray(); System.out.println(a);//asdfg }
4.字符串转集合
public static void main(String[] args) { String str ="a,s,d,f,g"; List list = Arrays.asList(str.split(",")); System.out.println(list);// [a, s, d, f, g] }
5.集合转数组
public static void main(String[] args) { List list = new ArrayList(); list.add('a'); list.add(1); list.add('c'); Object[] a = list.toArray(); System.out.println(Arrays.toString(a));// [a, 1, c] }
6.集合转化为字符串
public static void main(String[] args) { List list = new ArrayList(); list.add("张三"); list.add("李四"); String s = StringUtils.join(list, ""); System.out.println(s);//张三，李四 }
