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How to get the correct format of dateand time in mysql?

When I get the date and time in MySQL it retrieves it in this format:
2016-01-14 14:24:00.0
Where does the .0 come from and how do I get this format with Java:
2016-01-14 14:24:00

You can use 2 ways to do this.
Split the date string at '.'
String date = "2016-01-14 14:24:00.0";
String newDate = date.split("\\.")[0];
System.out.println(newDate);
Use SimpleDateFormat
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS");
Date date = sdf.parse("2016-01-14 14:24:00.0");
sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
System.out.println(sdf.format(date));

If you are getting date as string, you can use Format to get the format you need:
SELECT DATE_FORMAT(YourDateField, '%d-%m-%Y %T')
FROM YourTable
Have a look here for all possible formats

If you are getting your date as a java.sql.Timestamp, you can get the corresponding java.util.Date instance very easily and then format it to the desired string representation with a java.text.SimpleDateFormat class.

Java - SimpleDateFormat parse from String issue

I'm trying to parse the following string to a Date object:
String str = "04/15/2014 10:30:24"
I'm using SimpleDateFormat :
SimpleDateFormat sdf = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss");
java.util.Date orderDate = sdf.parse(str);
java.sql.Date orderSqlDate = new java.sql.Date(orderDate.getTime());
but orderSqlDate always returned: 04/15/2014 00:00:00
how to use SimpleDateFormat in java exactly?

The java.sql.Date javadoc states
To conform with the definition of SQL DATE, the millisecond values
wrapped by a java.sql.Date instance must be 'normalized' by setting
the hours, minutes, seconds, and milliseconds to zero in the
particular time zone with which the instance is associated.
If you're going to use java.sql.Date, there's no way around this.

You are also doing correct.
But to get the result in the format you want, you need to use .format("/your format/") method after parsing the string.
String date = "15/12/2014 10:42:24";
SimpleDateFormat dateParser = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss");
SimpleDateFormat formatter = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Date parseDate = dateParser.parse(date);
formatter.format(parseDate) // this will change format of date as you want.

I don't think the way you parse is wrong. Are you sure you print orderDate right ?
The following code demonstrates both parsing and formatting (printing).
public static void main(String[] args) {
String format = "MM/dd/yyyy HH:mm:ss";
try {
SimpleDateFormat sdf = new SimpleDateFormat(format);
Date orderDate = new SimpleDateFormat(format).parse("04/15/2014 10:30:24");
System.out.println(sdf.format(orderDate));
} catch (Exception e) {
e.printStackTrace();
}
}

Provide Locale in the SimpleDateFormat constructor, otherwise parsing might be dependant on your local settings:
SimpleDateFormat sdf = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss", Locale.ROOT);

convert a date object to Oracle timestamp type string

I want to convert a date object, ex: new Date(), to a string which has a format like Oracle's time stamp type, ex: 21-OCT-13 11.08.13.858000000 AM. I know I could just get each piece of information in the date object like day, month, year, hour, minute, ... to form the Oracle format string but I really want to know is there a utility to do that instead?

Using SimpleDateFormat#format() you would print a Date as
SimpleDateFormat sdf = new SimpleDateFormat("dd-MMM-yy hh.mm.ss.SSSSSSSSS a");
System.out.println(sdf.format(new Date()).toUpperCase());
Output :
21-OCT-13 10.01.38.000000614 AM
See JavaDocs for Date and Time patterns.

Try taking a look at SimpleDateFormats - That would be your best bet and easiest way of doing it.
Eg:
Date date = new Date();
SimpleDateFormat dateFormat = new SimpleDateFormat("hh:mm:ss"); //Hours:Minutes:Seconds
String strDate = dateFormat.format(date);

Use SimpleDateFormat.
Date date = new Date();
SimpleDateFormat sdf = new SimpleDateFormat("your_format_here"); // dd/MM/yy h:mm:ss a
String formattedDate = sdf.format(date);
System.out.println(formattedDate);

Current Date & Time in Java

I want the current date and time in the following format :
Date :YYYYMMDD
Time : HHMMSS
I tried the following
DateFormat dateFormat = new SimpleDateFormat("yyyyMMdd");
//get current date time with Date()
Date date = new Date();
System.out.println(dateFormat.format(date));
//get current date time with Calendar()
Calendar cal = Calendar.getInstance();
System.out.println(new Date().getTime());
By this I am getting the desired date output but the time is coming in this way 1341837848290.
The expected is HHMMSS.

Use format()
System.out.println(new SimpleDateFormat("HH:mm:SS").format(new Date()));
Date instance doesn't have any property to hold custom format, So you need to format the date instance to String with your custom format HH:mm:SS (See API doc for more detail)
See
IDEOne demo

try this
DateFormat dateFormat = new SimpleDateFormat("yyyyMMdd");
//get current date time with Date()
Date date = new Date();
System.out.println(dateFormat.format(date));
//get current date time with Calendar()
DateFormat timeFormat = new SimpleDateFormat("HHmmss");
Date d=new Date();
System.out.println(timeFormat.format(d);

Did you check out the joda-time library? Link here
With joda-time, you could easily call new DateTime(), call toString() on it and have this output, which may be more what you want:
public static void main(final String[] args) {
final DateTime d = new DateTime();
System.out.println(d.toString());
}
Output: 2012-07-09T14:54:13.366+02:00
Joda-Time is very powerful on the plus side. Of course, this is an extra lib you need to include, and if this is not possible or desired, another approach would probably be better.

I tried this:
SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd HHmmss");
Date date = Calendar.getInstance().getTime();
System.out.println(sdf.format(date));
Yields:
20120709 145518
First section is the date (20120709), the second section is the time(145518).
It seems that you have been using the wrong notation. I would recommend you take a look here for full details.

DateFormat dateFormat = new SimpleDateFormat("yyyyMMdd HH:mm:SS");
//get current date time with Date()
Date date = new Date();
System.out.println(dateFormat.format(date));
for more formatting refer API Doc

How to format a date String into desirable Date format

I was trying to format a string into date.
For this I have written a code:-
Calendar cal = Calendar.getInstance();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
System.out.println(sdf.format( cal.getTime() ));
This is fine..
But now I want to convert a string into a date formatted like above..
For example
String dt="2010-10-22";
And the output should be like this:-
2010-10-22T00:00:00
How do I do this?

String dt = "2010-10-22";
SimpleDateFormat sdfIn = new SimpleDateFormat("yyyy-MM-dd");
ParsePosition ps = new ParsePosition(0)
Date date = sdfIn.parse(dt, pos)
SimpleDateFormat sdfOut = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
System.out.println(sdfOut.format( date ));

This should do it for you, remember to wrap it in a try-catch block just in case.
DateFormat dt = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
try
{
Date today = dt.parse("2010-10-22T00:00:00");
System.out.println("Your Date = " + dt.format(today));
} catch (ParseException e)
{
//This parse operation may not be successful, in which case you should handle the ParseException that gets thrown.
//Black Magic Goes Here
}

If your input is going to be ISO, you could also look at using the Joda Time API, like so:
LocalDateTime localDateTime = new LocalDateTime("2010-10-22");
System.out.println("Formatted time: " + localDateTime.toString());

The same class you use for output formatting of dates can also be used to parse dates on input.
SimpleDateFormat reference
To use your example, to parse the sample date:
String dt = "2010-10-22";
SimpleDateFormat dateFormatter = new SimpleDateFormat("yyyy-MM-dd");
System.out.println(dateFormatter.parse(dt));
The fields that are not specified (ie. hour, minutes, etc) will be 0. So your same code can be used to format the date on output.

Date Format Example
Containing the Conversion of String Date object from one format to another