dsto.dfc.collections
Interface Cursor

All Known Implementing Classes:

ArrayIterator

public interface Cursor

A cursor is a more flexible way to move through a collection than an Iterator. A cursor can be moved rapidly back and forth by any number of units. It also remembers the current item it is pointing to.

Author:

Matthew Phillips

Method Summary

Object	current()
boolean	inside()
int	move(int units) Move the cursor left (negative units) or right (positive units).

Method Detail

move

int move(int units)

Move the cursor left (negative units) or right (positive units). This may cause the cursor to move outside the collection: if so, it stops just one unit to the left or right of the sequence and returns the actual number of items it moved past. A subsequent move of one unit in the other direction would put the cursor back to the first/last entry.

Parameters:

units - The number of units to move.

Returns:

The number of elements actually moved past, which may be less than the requested units if the cursor has moved outside the collection. For example, if the cursor was at the last element of the collection and a move of 1 unit was requested, this returns zero.

current

Object current()
               throws NoSuchElementException

Returns:

The current element the cursor is pointing to.

Throws:

NoSuchElementException - If the cursor is not inside the collection.

inside

boolean inside()

Returns:

True if the cursor is valid is within the collection).