Needed for printf() like formatting
  (replaces variable length argument lists
Possibly a good idea.
An example:
  public static void main(String[] args) {
  
    double sum2 = sum({1.2, 2.4, 3.5, 4.9});
    System.out.println(sum(array));
    
  }
  
  public static double sum(double[] x) {
  
    double sum = 0.0;
    for (int i = 0; i < x.length; i++) {
      sum += x[i];
    }
    return sum;
  } 
}
  
How is the type of the array determined?