question about the calendar class

I have the following lines of code

Calendar c=null;
c.set(2007, 2, 15);

According to the API, I am invoking the set method correctly

* set(int year, int month, int date)
Sets the values for the calendar fields YEAR, MONTH, and DAY_OF_MONTH *

http://java.sun.com/j2se/1.5.0/docs/api/index.html?java/util/Calendar.html

So why is the JVM complaining at runtime

* Exception in thread "main" java.lang.NullPointerException
at staffing.createManager.main(createManager.java:13) *

There is nothing in the API about this method throwing a NPE exception. Can someone tell me what is wrong with my method call?

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