/**
 * The InspectableList interface specifies a sequence of elements of
 * which each element is associated with a position.  The sequence
 * cannot be changed.
 *
 * @version     1.4	March 2, 2001
 * @author      Franck van Breugel
 * @see Position
 */
public interface InspectableList extends InspectablePositionalContainer 
{

    /**
     * Returns the first position of this sequence.
     * Throws an EmptyContainerException if this sequence is empty.
     * @return The first position of this sequence.
     * @exception EmptyContainerException if this sequence is empty.
     */
    public Position first() throws EmptyContainerException;

    /**
     * Returns the last position of this sequence.
     * Throws an EmptyContainerException if this sequence is empty.
     * @return The last position of this sequence.
     * @exception EmptyContainerException if this sequence is empty.
     */
    public Position last() throws EmptyContainerException;

    /**
     * Tests if the specified position is the first position of this
     * sequence.
     * @param position The position to be tested to be the first position
     * of this sequence.
     * @result true if the specified position is the first position
     * of this sequence, false otherwise.
     */
    public boolean isFirst(Position position);

    /**
     * Tests if the specified position is the last position of this
     * sequence.
     * @param position The position to be tested to be the last position
     * of this sequence.
     * @result true if the specified position is the last position
     * of this sequence, false otherwise.
     */
    public boolean isLast(Position position);

    /**
     * Returns the position before the specified position in this sequence.
     * Throws a BoundaryViolationException if the specified position is
     * the first position of this sequence.
     * @param position The position the predecessor of which is to be returned.
     * @return The position before the specified position in this sequence.
     * @exception BoundaryViolationException if the specified position is
     * the first position of this sequence.
     */
    public Position before(Position position) throws BoundaryViolationException;

    /**
     * Returns the position after the specified position in this sequence.
     * Throws a BoundaryViolationException if the specified position is
     * the last position of this sequence.
     * @param position The position the successor of which is to be returned.
     * @return The position after the specified position in this sequence.
     * @exception BoundaryViolationException if the specified position is
     * the last position of this sequence.
     */
    public Position after(Position position) throws BoundaryViolationException;
}