Dot Notation ends early

The example twitter object, the field id won't be reached. String[] parts returns length of 3 and the for loop starts at 1

First iteration: i = 1; 1 < 2 (true,continue in loop)
Second iteration: i =2; 2 < 2 (false, don't enter loop)

parts[2] is the "id" of the object. In order to not exit the loop early we need to evaluate 
i <= (parts.length - 1)
or
i < parts.length