public class Hello {
public static void main(String[] args) throws Exception{
System.out.println( System.currentTimeMillis());
long begin = System.currentTimeMillis();
print();
long end = System.currentTimeMillis();结束时间
System.out.println("耗时" + (end - begin) + "毫秒");
}
public static void print(){
for (int i = 0; i < 1000000000; i++) {
}
}
}
import java.text.SimpleDateFormat;
import java.util.Date;
public class Hello {
public static void main(String[] args) throws Exception {
Date time = new Date(1);
System.out.println(time);
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss SSS");
System.out.println(sdf.format(time));
Date time2 = new Date(System.currentTimeMillis() - 1000 * 60 *60 *24);
String str = sdf.format(time2);
System.out.println(str);
Date time3 = new Date(System.currentTimeMillis() - (long)1000 * 60 * 60 * 24 * 365);
System.out.println(sdf.format(time3));
}
}