java - Fibonacci Recursion? -

i have started learn recursion. program i'm asked make should take term input, , output corresponding fibonacci number. have far, it's showing error. what's wrong?

thanks in advance!

private void btnfindnumberactionperformed(java.awt.event.actionevent evt) {                                                   int term = integer.parseint(txtinputterm.gettext());     int number = fibonacci(term);     txtoutput.settext("fibonacci number " + term + " " + number); }                                               public int fibonacci (int term) {     if (term == 1) {         return term;     } else {        int number = fibonacci(term-1) + fibonacci(term-2);        return number;     } } 

imagine fibonacci term being 2. happen?

• term == 1 ? wrong, continue else...
• so try calling fibonacci(term-1) ( = fibonacci(1) ) + fibonacci(term-2) ( = fibonacci(0) )

ok, fibonacci(term-1) ( = fibonacci(1) )...

• term == 1 ? true, returning 1

ok, fibonacci(term-2) ( = fibonacci(0) )

• term == 1 ? false, because it's zero. , goes downhill there, since numbers negative , never step term == 1.

so, perhaps might wish think again if criteria should equal 1 or perhaps different.

as more technical explanation, since mentioned in comments: when calling method, data stored on called "stack". if call, example, method a, calls b, data (at least) 2 methods stored on stack. if b again calls method, again, again... stack overflow, dreaded stackoverflowexception. happens when getting return conditions wrong on recursive method.

and last comment: don't recursive methods unless need to. imagine need learn now, in future, don't forget recursion elegant concept - in math, not in coding, tends lead problems (like 1 - , fact calculating fibonacci recursively worst way so).