ArrayEnumeration.java Source code

Introduction

Here is the source code for ArrayEnumeration.java

Source

import java.lang.reflect.Array;
import java.util.Enumeration;

class ArrayEnumeration implements Enumeration {
    private final int size;

    private int cursor;

    private final Object array;

    public ArrayEnumeration(Object obj) {
        Class type = obj.getClass();
        if (!type.isArray()) {
            throw new IllegalArgumentException("Invalid type: " + type);
        }
        size = Array.getLength(obj);
        array = obj;
    }

    public boolean hasMoreElements() {
        return (cursor < size);
    }

    public Object nextElement() {
        return Array.get(array, cursor++);
    }
}

public class MainClass {

    public static void main(String args[]) {
        Object obj = new int[] { 2, 3, 5, 8, 13, 21 };
        Enumeration e = new ArrayEnumeration(obj);
        while (e.hasMoreElements()) {
            System.out.println(e.nextElement());
        }
        try {
            e = new ArrayEnumeration("Not an Array");
        } catch (IllegalArgumentException ex) {
            System.out.println(ex.getMessage());
        }
    }
}