Yes.
Sometimes translating the math-like definition into Java is all you need to do. But sometimes you need to think about what happens when the program runs. In this dynamic view you think about the sequence of events as the method is actually executing.
Look at the TriangleTester program again.
Here is a statement from main():
int result = tri.Triangle( 4 );
When a statement like this executes,
the method
Triangle() is said to be activated
with an argument of 4.
It does some computation and returns a result, 10.
Picture this as at right.
Examine the code. Say that Triangle()
has been activated with a parameter of 4.
The if statement selects the false branch.
What happens next?
public int Triangle( int N )
{
if ( N == 1 )
return 1;
else
return N + Triangle( N-1 );
}