What is the sum of this 'byte' array?

A byte array of size 256 is filled with integers 0 to 255. All values in the byte array are added to produce a sum:

byte[] bytes = new byte[256];

// fill the array from 0 to 255
for(int i=0; i < bytes.length; ++i)
    bytes[i] = (byte)i;

// calculate sum of all        
int sum = 0;
for(byte b : bytes)
  sum += b;

What will be the value of sum?