java字符串、数组、集合之间的转换

import java.util.Arrays;
import java.util.List;

import static java.util.Arrays.sort;

/**
 * @author 孙永潮
 * @date 2024/01/04
 */
public class StringSplitDemo {
    public static void main(String[] args) {
        String str = "1,2,9,4,5,6,7,8,3";
        System.out.println(str);

        //字符串 拆分为数组
        String[] split = str.split(",");
        //排序
        sort(split);

        for (String e : split){
            System.out.print(e);
            System.out.print(" ");
        }
        System.out.println();

        System.out.println("转换为带 [] 的字符串");
        String toString = Arrays.toString(split);
        System.out.println(toString);

        //数组 转换为List
        List<String> list = Arrays.asList(split);

        //list 转换为数组
        String[] strings = list.toArray(new String[0]);
        for (String e : strings){
            System.out.print(e);
            System.out.print(" ");
        }

        String str010 = "000010";
        System.out.println(str010);

        //list 也可以转换 为 int类型的数组
        int[] array = list.stream()
                .mapToInt(Integer::parseInt)
                .toArray();
        for (int i : array){
            System.out.print(i);
            System.out.print(" ");
        }

        //int会自动去掉前边的0
        int n = Integer.parseInt(str010);
        System.out.println(n);
    }
}