edu.kzoo.grid
Class BoundedGrid

java.lang.Object
  |
  +--edu.kzoo.grid.Grid
        |
        +--edu.kzoo.grid.BoundedGrid

public class BoundedGrid

extends Grid

Grid Container Package:
A BoundedGrid is a rectangular, bounded two-dimensional container data structure. It can contain any kind of object that can be modeled using an extension of the GridObject class. For example, a grid could be used to model a board for a tic-tac-toe or chess game, an environment of fish for a marine biology simulation, etc.

A BoundedGrid is implemented as a two-dimensional array corresponding to the dimensions of the grid. This gives it the following time and space characteristics:

numObjects		O(1)
allObjects		O(r * c)
isEmpty, objectAt		O(1)
add		O(1)
remove		O(1)
space		O(r * c)

where r is the number of rows and rc is the number of columns in the grid.

The BoundedGrid class and its internal 2D array implementation are based on the College Board's BoundedEnv class, as allowed by the GNU General Public License.

Version:

13 December 2003

Author:

Alyce Brady

Nested Class Summary

protected static class

BoundedGrid.Array2DGridRep The Array2DGridRep class represents an internal bounded grid using a two-dimensional array.

Nested classes inherited from class edu.kzoo.grid.Grid

Grid.BoundedGridValidityChecker, Grid.UnboundedGridValidityChecker, Grid.ValidityChecker

Field Summary

Fields inherited from class edu.kzoo.grid.Grid

includeDiagonals, internalRep, UNBOUNDED

Constructor Summary

BoundedGrid(boolean includeDiagonalNeighbors, int rows, int cols)
Constructs an empty BoundedGrid object with the given dimensions.

BoundedGrid(int rows, int cols)
Constructs an empty BoundedGrid object with the given dimensions.

Method Summary

int	numCols() Returns number of columns in this grid.
int	numRows() Returns number of rows in this grid.

Methods inherited from class edu.kzoo.grid.Grid

add, allObjects, getDirection, getNeighbor, isEmpty, isValid, neighborsOf, numAdjacentNeighbors, numObjects, objectAt, randomDirection, remove, remove, removeAll, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

BoundedGrid

public BoundedGrid(int rows,
                   int cols)

Constructs an empty BoundedGrid object with the given dimensions. A cell's neighbors include only the cells to its north, south, east, and west, not the cells on the diagonals. (Precondition: rows > 0 and cols > 0.)

Parameters:

rows - number of rows in BoundedGrid

cols - number of columns in BoundedGrid

Throws:

java.lang.IllegalArgumentException - if the precondition is not met

BoundedGrid

public BoundedGrid(boolean includeDiagonalNeighbors,
                   int rows,
                   int cols)

Constructs an empty BoundedGrid object with the given dimensions. Each cell in this grid will have at most four or eight adjacent neighbors, depending on the value of the includeDiagonalNeighbors parameter. Cells along the grid boundaries will have fewer than the maximum four or eight neighbors. If includeDiagonalNeighbors is true, a cell's adjacent neighbors include the cells to its north, south, east, and west and the cells on the diagonals, to the northeast, southeast, northwest, and southwest. If includeDiagonalNeighbors is false, a cell's adjacent neighbors include only the four cells to its north, south, east, and west. (Precondition: rows > 0 and cols > 0.)

Parameters:

includeDiagonalNeighbors - whether to include the four diagonal locations as neighbors

rows - number of rows in BoundedGrid

cols - number of columns in BoundedGrid

Throws:

java.lang.IllegalArgumentException - if the precondition is not met

Method Detail

numRows

public int numRows()

Returns number of rows in this grid.

Specified by:

numRows in class Grid

Returns:

the number of rows in this grid

numCols

public int numCols()

Returns number of columns in this grid.

Specified by:

numCols in class Grid

Returns:

the number of columns in this grid