list => sort

Collections => list => sort 

import java.util.ArrayList;
import java.util.Collections;
import java.util.Random;
public class Arry_Sort {
    public static void main(String[] args) {
        ArrayList <Integer> myList = new ArrayList<>();
        Random generator = new Random(); // Random 객체 생성
        int i; // index
        for (i = 0; i < 10; i++) {
            myList.add(generator.nextInt(20));
        }
        System.out.println("before => " + myList);
        Collections.sort(myList);
        System.out.println("after => " + myList);
    }
}