Java common utils test

package com.utils;import java.io.File;import java.util.Random;import java.util.UUID;public class Common {private static Random random = new Random();public String getUUID() {String id = UUID.randomUUID().toString();return id;}public String getUUIDByString(String str) {String id = UUID.fromString("38400000-8cf0-11bd-b23e-10b96e4ef00d").toString();return id;}public Number getRandomNumber() {Number ranNumber = 0;ranNumber = random.nextFloat()*10;return ranNumber;}public Integer getRandom(Integer from, Integer to) {return from + random.nextInt(to - from);}public String[] getFileList() {File file = new File("C:/Downloads");String[] liSt = file.list();for (String path: liSt) {System.out.println(path);}return liSt;}}