Java 生成指定范围内的随机时间

package test;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Random;

public class Test2 {
    public static void main(String[] args) throws Exception {
    	randomDate("2022-05-10", null);
    	randomDate("2022-05-10", "2022-05-11");
    }
    
    /**
     * 生成随机时间
     * @param beginDate	开始时间范围
     * @param endDate	结束时间范围
     * @return
     * @throws ParseException 
     */
    public static String randomDate(String beginDate,String endDate) throws ParseException{
    	//格式化时间
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        
        //如果不需要时分秒，下面拼接00:00:00也不需要
//        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        //随机起始时间拼接时分秒
        beginDate += " 00:00:00";
        //解析时间
        Date d1 = sdf.parse(beginDate);
        long before = d1.getTime();
        
        //默认获取当前时间
        Date d2 = new Date();
        if(endDate != null){
        	//拼接时分秒
        	endDate += " 00:00:00";
        	d2 = sdf.parse(endDate);
        }
        long after = d2.getTime();
        
        Random r = new Random();
        long randomDate = (long) (before + (r.nextFloat() * (after - before + 1)));
        
        String date = sdf.format(randomDate);
        System.out.println(date);
        return date;
    }

}