Convert java.util.Date to java.sql.Date and Basic date

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Date Class

Parameter	Explanation
No parameter	Creates a new Date object using the allocation time (to the nearest millisecond)
long date	Creates a new Date object with the time set to the number of milliseconds since "the epoch" (January 1, 1970, 00:00:00 GMT

Convert java.util.Date to java.sql.Date

java.util.Date to java.sql.Date conversion is usually necessary when a Date object needs to be written in a database.

java.sql.Date is a wrapper around millisecond value and is used by JDBC to identify an SQL DATE type

In the below example, we use the java.util.Date() constructor, that creates a Date object and initializes it to represent time to the nearest millisecond. This date is used in the convert(java.util.Date utilDate) method to return a java.sql.Date object

Example

public class UtilToSqlConversion
{
	public static void main(String args[])
	{
		java.util.Date utilDate = new java.util.Date();
		System.out.println("java.util.Date is : " + utilDate);
		java.sql.Date sqlDate = convert(utilDate);
		System.out.println("java.sql.Date is : " + sqlDate);
		DateFormat df = new SimpleDateFormat("dd/MM/YYYY - hh:mm:ss");
		System.out.println("dateFormated date is : " + df.format(utilDate));
	}
	private static java.sql.Date convert(java.util.Date uDate)
	{
		java.sql.Date sDate = new java.sql.Date(uDate.getTime());
		return sDate;
	}
}

Result:

java.util.Date is : Fri Dec 29 17:23:15 UTC 2023
java.sql.Date is : 2023-12-29
dateFormated date is : 29/12/2023 - 05:23:15

java.util.Date has both date and time information, whereas java.sql.Date only has date information

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A basic date output

Using the following code with the format string yyyy/MM/dd hh:mm.ss, we will receive the following output

2023/12/29 10:45.59

// define the format to use
String formatString = "yyyy/MM/dd hh:mm.ss";
 
// get a current date object
Date date = Calendar.getInstance().getTime();
 
// create the formatter
SimpleDateFormat simpleDateFormat = new SimpleDateFormat(formatString);
 
// format the date
String formattedDate = simpleDateFormat.format(date);
 
// print it
System.out.println(formattedDate);
 
// single-line version of all above code
System.out.println(new SimpleDateFormat("yyyy/MM/dd hh:mm.ss").format(Calendar.getInstance().getTime()));
 

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