Date Time conversion in Java

Package test;
Import java.text.ParseException;

Import Java.text.SimpleDateFormat; public class TestDate {public static void main (string[] args) throws ParseException {java.util.Date udate = new Java . util.
		Date ();

		Java.sql.Date sdate = new Java.sql.Date (0);
		SimpleDateFormat sdfdate = new SimpleDateFormat ("Yyyy-mm-dd");
		SimpleDateFormat sdftime = new SimpleDateFormat ("HH:mm:ss");

		SimpleDateFormat sdfdatetime = new SimpleDateFormat ("Yyyy-mm-dd HH:mm:ss"); Converts the Date in the Util package to the Sql.date udate.gettime ();

		Gets a long sdate = new Java.sql.Date (Udate.gettime ()); GetParameter is a string that converts the string date "2017-08-08" to Java.sql.Date//1. Converts the string date to Java.util.Date//2 through Simpledateformat.parse (String str). Get long//3 via Java.util.Date.getTime ().
		New Java.sql.Date (Java.util.Date.getTime ());
		Java.util.Date judate = Sdfdate.parse ("2017-8-1");
		Long ldate = Judate.gettime ();
		Java.sql.Date jsdate = new Java.sql.Date (ldate);
		System.out.println (judate);
		System.out.println (ldate); SYstem.out.println (jsdate);
	SYSTEM.OUT.PRINTLN (Sdatetosqldate (null, "Yyyy-mm-dd HH:mm:ss", "1990-1-1 0:0:0")); public static Java.sql.Timestamp Sdatetosqldate (string date, string pattern, string defaultdate) {try {Simpleda
			Teformat SDF = new SimpleDateFormat (pattern);
		
			Long ldate = sdf.parse (date!= null? date:defaultdate). GetTime ();
		return new Java.sql.Timestamp (ldate); 
		catch (ParseException e) {e.printstacktrace ();
	return null;
 }
}

The Java.sql.Date type dates the method of construction: Date (long date), which requires a long date dated, and the date we do the item fetch (getparameter) from the page is a string type.

The first step requires us to convert the string date to the date of the Util type, which requires the format of the date: SimpleDateFormat

SimpleDateFormat SDF = new SimpleDateFormat ("Yyyy-mm-dd HH:mm:ss");

Java.util.Date judate = Sdf.parse ("2017-8-1 20:32:25");

The second step converts date dates of the Util type to long date

Judate.gettime ()

The third step is to convert a long date to a SQL type using the method of constructing SQL type Date
New Java.sql.Date (Judate.gettime ()); Common methods of SimpleDateFormat class

NO	Method	type	Description
1	Public SimpleDateFormat (String pattern)	Structure	The build uses the default format locale to set the given pattern and default date format symbol SimpleDateFormat.
2	Public final String format (date date)	Ordinary	Format a date As String data
3	Public Date Parse (String source) throws ParseException	Ordinary	Format a string as date data