Java - collection and array tables

Question

i have a little task in java generated from an exercise randomizer application. The instructions are:

Write a class named Vulgarist with a public identifier which must contain a public static method mes. This method gets as arguments a Vector type collection of Long and two tables with boolean type elements. The two tables and the collection have the same number of elements. The method returns as a result a Vector type collection of Long consisting of the elements of the collection of the first argument for which the corresponding element of the first table is the value true and the corresponding element of the second table is the value false.

My code is:

import java.util.Vector;
public class Vulgarist {
    public static Vector<Long> mes(Vector<Long> v1, boolean a[], boolean b[]) {
        Vector<Long> v2 = new Vector<>();
        while ((v1.size() == b.length) && (v1.size() == a.length)
            && (a.length == b.length)) {
            for (int i = 0; i <= a.length; i++) {
                if ((a[i] == true) && (b[i] == false)) {
                    v2.add(v1.get(i));
                }
            }
        }
        return v2;
    }
}

The result i get from the application is "The method mes was not implemented according to the instructions" Message Error : null

Can anyone help me find what i did wrong?

sstan · Accepted Answer · 2015-12-05 03:42:20Z

1

There are 2 main problems:

Your while loop is unnecessary, and will always evaluate to true, thus resulting in an endless loop. Just remove the while loop. It doesn't accomplish anything.
The for condition i <= a.length should be changed to i < a.length to avoid getting an IndexOutOfBoundsException. Remember that the last available index on an array is length - 1.

answered Dec 5, 2015 at 3:42

sstan

36.8k7 gold badges54 silver badges72 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

zatara90 Over a year ago

Wow at first i had no while loop and added it later cause i thought that it was the reason of my problem. Turns out, all this time the problem was in the for as u correctly suggested. Such a small thing. Thank you.

Collectives™ on Stack Overflow

Java - collection and array tables

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related