Differences between date Yyyy-mm-dd HH:mm:ss and Yyyy-mm-dd Hh:mm:ss in Java

The differences between date yyyy-mm-dd HH:mm:ss and Yyyy-mm-dd hh:mm:ss in Java:

Hh:24 Hour System

Hh:12 Hour System

 PackageTime ;ImportJava.text.DateFormat;ImportJava.text.SimpleDateFormat;Importjava.util.Date;/*** Created by sheting on 10/20/2017*/ Public classTest { Public Static voidMain (string[] args) {//HH is a 12-hour system .DateFormat DateTimeFormat =NewSimpleDateFormat ("Yyyy-mm-dd hh:mm:ss"); String strbegindate= Datetimeformat.format (NewDate ());  System.out.println (strbegindate); //2017-10-20 11:59:23//HH is a 24-hour system .DateFormat DATETIMEFORMAT2 =NewSimpleDateFormat ("Yyyy-mm-dd HH:mm:ss"); String StrBeginDate2= Datetimeformat2.format (NewDate ());  System.out.println (STRBEGINDATE2); //2017-10-20 11:59:23    }}

Differences between date yyyy-mm-dd HH:mm:ss and Yyyy-mm-dd hh:mm:ss in Java