JAVA 将时间戳转化成时间的三种写法_string.valueof(timestamp)作用

import java.text.SimpleDateFormat;
import java.util.Date;
 
public class Demo1 {
	public static void main(String[] args) {
		Long timeStamp = System.currentTimeMillis();  //获取当前时间戳
        SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String sd = sdf.format(Long.parseLong(String.valueOf(timeStamp)));
        String sd2 = sdf.format(new Date(Long.parseLong(String.valueOf(timeStamp))));
        String sd3 = sdf.format(timeStamp);
        System.out.println("格式化结果：" + sd);
        System.out.println("格式化结果：" + sd2);
        System.out.println("格式化结果：" + sd3);
	}
}