Higher order function and threads

Question

Does anyone knows if I define an interface ApplyObj with a binary function f as it's only method; the binary operator that we want to pass as an argument into the reduction is then declared as a class that implements this interface. How to I do that??
Taking example.
applic is the function to excute. and this applic can store instructions to add, concat or minus. Then I have this set of array which can be alpha or int array, passing the function in, it's suppose to create threads to get the result
e.g array[3] store [0]= 2 [1]=4 and [2]=8
after the first round will result to array[0] and array[1] to add each other and result stored in [0]. since [2] does not have a neighbour [3], [2] after step 1 still have the value of 8
then step 2 will result to [0] which stores the step 1 results which is 2+4=6, [0] will then add with [2] and the final results [0]=14.
Just how can I program like this?
1st can anyone tell me... how to decipher a higher order function that is pass in as a object?
Thanks

Answer 1

Sounds to me like you want this:public interface ApplyObj
    public int[] applic(int[] args);
}Then e.g.public class Add implements ApplyObj
    public int[] applic(int[] args)
        int[] result = new int[(args.length + 1) / 2];
        for (int i = 0; i < args.length; i += 2)
            result[i / 2] = args[i] + args[i + 1];
        // Deal with the last element of an odd length array
        if (args.length % 2 == 1)
            result[result.length - 1] = args[args.length - 1];
        return args;
}Warning: this code is untested. Note: pizza is a superset of Java which has proper higher order functions. Maybe you should use that instead.
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