///////    Iterable.java    ///////
import java.util.Enumeration;

public interface Iterable
{   /** Sets up and returns a new iterator.
     *    using default (forward) traversal
     */
     Enumeration elements();

    /** Sets up and returns a new iterator.
     *    using given traversal scheme
     */
     Enumeration elements(int scheme);

    /** Some constants to indicate traversal scheme.
     */
     static final int FORWARD = 0;
     static final int BACKWARD = 1;
     static final int DEPTHFIRST = 2;
     static final int BREADTHFIRST = 3;
}