I tried to find the mode of elements in an array without using any of Java Array's methods

Mode.java

import java.util.Arrays;

public class Mode {
    private ModeOccurrence<Object, Integer> modeOccurrence;

    Mode() {
        this.modeOccurrence = new ModeOccurrence<>(null, -1);
    }

    public static void main(String[] args) {
        if (args.length == 0) {
            System.err.println("Man, warrisdat?");
            System.exit(1);
        }

        if (args.length == 1) {
            System.out.println(args[0]);
            System.exit(0);
        }

        Mode modeFinder = new Mode();
        ModeOccurrence<Object, Integer> modeAndCount = modeFinder.findMode(args);
        System.out.println(modeAndCount);

    }

    public ModeOccurrence<Object, Integer> findMode(Object[] array) {
        Object[] copyOfArguments = duplicateArray(array);
        Arrays.sort(copyOfArguments);

        Object mode = null;
        int modeCount = 0;
        Object previousElement = copyOfArguments[0];
        int currentElementCount = 0;

        for (int i = 0; i < copyOfArguments.length; i++) {
            Object currentElement = copyOfArguments[i];
            // Check whether current element is same as previous
            if (currentElement.equals(previousElement)) {
                // if previous and current element are the same
                // increment count for number of appearances of current
                currentElementCount++;
            } else {
                // otherwise change cached previous to current element
                if (currentElementCount > modeCount) {
                    // if appearances of current element is highest so far
                    // save current element as mode and currentElementCount as mode count
                    mode = previousElement;
                    modeCount = currentElementCount;
                }
                previousElement = currentElement;

                // reset current element count
                currentElementCount = 1;
            }

            if ( i == copyOfArguments.length - 1 ) {
                if (currentElementCount > modeCount) {
                  mode = currentElement;
                  modeCount = currentElementCount;
                }
            }
        }

        this.modeOccurrence.mode = mode;
        this.modeOccurrence.modeCount = modeCount;

        return modeOccurrence;
    }

    public static Object[] duplicateArray(Object[] original) {
        Object[] copy = new Object[original.length];
        System.arraycopy(original, 0, copy, 0, original.length);

        return copy;
    }

    class ModeOccurrence<E, Integer> {
        public final E mode;
        public final int modeCount;

        ModeOccurrence(E mode, int modeCount) {
            this.mode = mode;
            this.modeCount = modeCount;
        }

        public String toString() {
          return String.format("%s(%d)", mode.toString(), this.modeCount);
        }
    }
}