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// Test to change datetime items in text form
SimpleDateFormat sdfIn = new SimpleDateFormat( "dd.mm.yyyy" );
SimpleDateFormat sdfOut = new SimpleDateFormat( "yyyy.mm.dd" );
String strIn = "25.11.2023";
Date dt = sdfIn.parse( strIn );
String strOut = sdfOut.format( dt );
System.out.printf( "+++ Convert date format: '%s' -> '%s'%n", strIn, strOut );
...