Time Date Base operation

I. Get the current system time and date and format the output:

Import Java.util.Date;
Import Java.text.SimpleDateFormat;

public class Nowstring {
public static void Main (string[] args) {
SimpleDateFormat df = new SimpleDateFormat ("Yyyy-mm-dd HH:mm:ss");//Set Date format
System.out.println (Df.format (new Date ()));//new Date () to get the current system time
}
}

Two. The date in the database is only output in the form of year-month-day, which can be used in two ways:

1. CONVERT () Convert function:

String sqlst = "SELECT CONVERT (varchar), bookdate,126) as convertbookdate from RoomBook where bookdate between ' 2007-4-1 0 ' and ' 2007-4-25 ';

System.out.println (rs.getstring ("convertbookdate"));

2, the use of SimpleDateFormat class:

To enter two Java packages first:

Import Java.util.Date;
Import Java.text.SimpleDateFormat;

And then:

Define date format: SimpleDateFormat SDF = new SimpleDateFormat (YY-MM-DD);

The SQL statement is: String sqlstr = "Select Bookdate from RoomBook where bookdate between ' 2007-4-10 ' and ' 2007-4-25 '";

Output:

System.out.println (Df.format (Rs.getdate ("bookdate"));

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Methods for getting the current date and time in Java

Import Java.util.Date;
Import Java.util.Calendar;

Import Java.text.SimpleDateFormat;

public class testdate{
public static void Main (string[] args) {
Date now = new Date ();
SimpleDateFormat DateFormat = new SimpleDateFormat ("Yyyy/mm/dd HH:mm:ss");//You can easily modify the date format

String hehe = Dateformat.format (now);
SYSTEM.OUT.PRINTLN (hehe);

Calendar C = calendar.getinstance ();//Can be modified individually for each time domain

int year = C.get (calendar.year);
int month = C.get (calendar.month);
int date = C.get (calendar.date);
int hour = C.get (Calendar.hour_of_day);
int minute = C.get (Calendar.minute);
int second = C.get (Calendar.second);
SYSTEM.OUT.PRINTLN (Year + "/" + month + "/" + Date + "" +hour + ":" +minute + ":" + second);
}
}

Sometimes you convert a string of time to a date type, and you can convert the time string you just got to date type in the following way.

SimpleDateFormat sdf=new SimpleDateFormat ("Yyyy-mm-dd");

Java.util.Date Time=null;
try {
Time= Sdf.parse (Sdf.format (New Date ()));

} catch (ParseException e) {

E.printstacktrace ();
}

Java date subtraction get days

public class Dat {
 
 static simpledateformat H; 
 
 public static void Test (date date, int m) {
 H = new SimpleDateFormat ("Yyyy-mm-dd HH:mm:ss"); 
 String n = h.format (date); 
 
 String myString = dateformat.getdateinstance (). Format (date); 
 System.out.println ("After formatting:" + myString); 
 
 Timestamp time = timestamp.valueof (n); 
 
//Days plus (minus) days 
 long L = time.gettime () + * * * m * +; 
 Time.settime (l); 
 System.out.println ("Calculated date:" + time); 
} 
 public static void Main (String arg[]) {
 Date date=new date (108,04,02); 
 Test (date,5); 
 
} 
 
} 
 
 

Date date1 = new SimpleDateFormat ("Yyyy-mm-dd"). Parse ("2006-06-08");

  Date date2 = new SimpleDateFormat ("Yyyy-mm-dd"). Parse ("2006-06-12");

Long L = date1.gettime ()-date2.gettime () >0? Date1.gettime ()-date2.gettime ():

   Date2.gettime ()-date1.gettime ();

System.out.println (l/1000+ "s");

Date subtraction to get a difference

  Long day = (Date1.gettime ()-date2.gettime ())/(24*60*60*1000) >0? (Date1.gettime ()-date2.gettime ())/(24*60*60*1000):

   (Date2.gettime ()-date1.gettime ())/(24*60*60*1000);

System.out.println ("Date of Difference:" +day);

Time Date Base operation