java - get today's date and time as string

I am new to Java and trying to use Calendar object to get date and time of now as a string. I am particularly stuck at object and object conversions.

Here is the format I need (as a string):
2016-03-30T14:21:00Z

If I could just get the date and time format right, I could play around with the string but I am struggling with deprecated methods.

Thank you for replies