Arrays and enhanced for loops?

Question

Can someone please explain what is going on in this method?

class test{  
public static void main(String args[])
{
   int[] x = new int[4]; 
   int[] xy = new i         


        

Answer 1

It should be straight-forward to find out, if you trace through using debugger.

In brief, it is getting each value in x, and use the value as index to increment corresponding value in xy.

It will be more obvious if you initialize both array with meaningful values:

int[] x = {1,1,3,3}
int[] xy = new int[4]; // initialized to 0 by default

after your piece of code, you will find xy containing {0,2,0,2}.

---

You should understand how enhanced-for-loop is expanded for array:

for (T v : arr) {
    // do something 
}

is transformed to

for (int i = 0; i < arr.length; ++i) {
    T v = arr[i];
    // do something 
}

Obviously your understanding on how enhanced for loop being expanded is wrong.