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Printing out datetime in a specific format in Java?

I want to print out datetime in java in a specific format. I have this C# code which prints out the datetime in this format.
DateTime value = new DateTime(2010, 1, 18);
Console.WriteLine(value);
Console.WriteLine(value == DateTime.Today);
The result is - 1/18/2010 12:00:00 AM
Now, I want to write a java code that prints out the datetime in the same format. I used the joda.time library. This is what I tried so far.
DateTime today = new DateTime();
System.out.println(today.toString(“yyyy-MMM-dd”));
How can I pass the year,month and day as the constructor in the DateTime in java and print out in the above format.

Approach 1: Using java.time.LocalDateTime. (Strongly Preferred)
DateTimeFormatter dtf = DateTimeFormatter.ofPattern("yyyy/MM/dd HH:mm:ss");
LocalDateTime now = LocalDateTime.now();
System.out.println(dtf.format(now)); //2016/11/16 12:08:43
Approach 2: Using java.util.Date.
DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Date date = new Date();
System.out.println(dateFormat.format(date)); //2016/11/16 12:08:43
Approach 3: Using java.util.Calendar.
DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Calendar cal = Calendar.getInstance();
System.out.println(dateFormat.format(cal)); //2016/11/16 12:08:43

If you need date in 24 hour system then use this approach
SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy HH:mm:ss");
Date custDate = new Date();
System.out.println(sdf.format(custDate));
Please note in 24 hour system there is no need to show AM/PM.
If you want date in 12 hour system then use below approach
SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy hh:mm:ss a");
Date custDate = new Date();
System.out.println(sdf.format(custDate));
"a" in the date format will help to show AM/PM.
Please import below classes for above code to work
java.text.SimpleDateFormat
java.util.Date

LocalDate.of(2010, 1, 18).atStartOfDay().format(DateTimeFormatter.ofPattern("MM/dd/yyyy HH:mm:ss a"))
or
LocalDate.of(2010, 1, 18).atTime(12, 0, 0).format(DateTimeFormatter.ofPattern("MM/dd/yyyy HH:mm:ss a"));
if you want to add the time too

Please try to this one
public void Method(Datetime time)
{
time.toString("yyyy-MM-dd'T'HH:mm:ss"));
}

Why won't my SimpleDateFormat convert correctly?

I have my Date as String: 2014-06-23 22:00
To get the Date as java.util.date I parse it by using SimpleDateFormat
Date listDate = new Date();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-DD HH:mm",Locale.GERMANY);
listDate = sdf.parse(gameList.get(position).getTime());
but my output
System.out.println(listDate)
is 2014-04-118 19:37
What's going on here??

DD should be dd (in small) below are the available formats in Java7

Java Date format weird

I have an issue where I would like to get the start of the day, however it seems to be setting it to 12:00 via automatic.
SimpleDateFormat dfFull = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
String todayDate = dfFull.parse("2014-06-06 00:00:00");
today = dfFull.format(todayDate);
System.out.println(today);
Why is this spitting out:
2014-06-06 12:00:00
The 12:00:00 is the issue

That is because hh represents the hour in 12 hour format. You need to use HH instead.
SimpleDateFormat dfFull = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Have a look at the docs for more info.
Also, on a side note, there is a typo in your code.
SimpleDateFormat dfFull = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date todayDate = dfFull.parse("2014-06-06 00:00:00"); // todayDate must be of type Date and not String
String today = dfFull.format(todayDate); // today should be of type String
System.out.println(today);

You should use HH for hours in this case.
SimpleDateFormat dfFull = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String todayDate = dfFull.parse("2014-06-06 00:00:00");
today = dfFull.format(todayDate);
System.out.println(today);
Now you will get the out put as
2014-06-06 00:00:00
And again if you use hh that mean you are using 12 hour format while HH means 24 hour format
So

Calculating Date in Java

Ok so I am trying to create a date in this format:
SimpleDateFormat dateformat = new SimpleDateFormat("dd-MM-yy");
I am having trouble calculating that date so that it gives me 1/1/13.
Date newdate = new Date (136199001);
String date = dateformat.format(newdate);
However I can't work out how to do it to get to my desired date. I know I am suppose to work it out from 01/01/70 but I am having trouble. The question : what is the formula to work the date out?

I would say that what you are looking for is this:
new SimpleDateFormat("dd/MM/yy").parse("1/1/13");

You can use calendar object for a specific date. It is much easier.
Calendar cal = Calendar.getInstance();
cal.set(2013, 0, 1); //1st january 2013
Date date = cal.getTime();
SimpleDateFormat dateformat = new SimpleDateFormat("dd-MM-yy");
String dateStr = dateformat.format(date);

How to parse String "24-10-2012" into Date ( dd-mm-yyyy) format?

I am using jdk- 1.6.
I am try to parse String "24-10-2012" date to Date (24-10-2012) but i am getting this error:
java.text.ParseException: Unparseable date: "18-11-2012"
java.text.DateFormat.parse(DateFormat.java:354)
I am parsing like this:
SimpleDateFormat formatter = new SimpleDateFormat("dd-MM-yyyy");
String currentDate = "24-10-2012";
Date date = formatter.parse(currentDate);

SimpleDateFormat formatter = new SimpleDateFormat("dd-MM-yyyy");
String currentDate = "24-10-2012";
System.out.println(formatter.parse(currentDate));
prints
Wed Oct 24 00:00:00 CEST 2012
Your problem cannot be reproduced with the code you have posted.
My hypothesis: your exception is thrown from a piece of code other than the one you are accusing of the error. You could try carefully analyzing the stack trace in order to track down the real culprit.

Date in java does not hold any format. Read more...

When I run
SimpleDateFormat formatter = new SimpleDateFormat("dd-MM-yyyy");
String currentDate = "24-10-2012";
Date date = formatter.parse(currentDate);
System.out.println(date);
System.out.println(formatter.format(date));
I get
Wed Oct 24 00:00:00 BST 2012
24-10-2012
which is as I expected. Can you clarity what the problem is?

You can use this for the format "dd-mm-yyyy"
SimpleDateFormat formatter = new SimpleDateFormat("dd-MM-yyyy");
String currentDate = "24-10-2012";
Date date = formatter.parse(currentDate);
System.out.println(formatter.format(date));

import java.util.Date;
import java.text.SimpleDateFormat;
public class SimpleFormatDate
{
public static void main(String args[]){
Date todaysDate = new java.util.Date();
// Formatting date into yyyy-MM-dd HH:mm:ss e.g 2008-10-10 11:21:10
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String formattedDate = formatter.format(todaysDate);
System.out.println("Formatted date is ==>"+formattedDate);
// Formatting date into yyyy-MM-dd e.g 2008-10-10
formatter = new SimpleDateFormat("yyyy-MM-dd");
formattedDate = formatter.format(todaysDate);
System.out.println("Formatted date is ==>"+formattedDate);
// Formatting date into MM/dd/yyyy e.g 10/10/2008
formatter = new SimpleDateFormat("MM/dd/yyyy");
formattedDate = formatter.format(todaysDate);
System.out.println("Formatted date is ==>"+formattedDate);
}
}
output
Formatted date is ==>2008-10-10 13:03:54
Formatted date is ==>2008-10-10
Formatted date is ==>10/10/2008

Wait a second.. Why u need to parsing that if u have a right value ?
Anyway, i use this :
SimpleDateFormat oFormat = new SimpleDateFormat("yyyy-MM-dd");
String sDate = oFormat.format("24-10-2012");
it will appearing date like 2012-10-24. So if u want to parsing to dd-MM-yyyy, u just need change the format to what u want.
NB : Sorry if my english is bad. :D