info.gridworld.grid
Interface Grid<E>

All Known Implementing Classes:

AbstractGrid, BoundedGrid, UnboundedGrid

public interface Grid<E>

Grid provides an interface for a two-dimensional, grid-like environment containing arbitrary objects.
This interface is testable on the AP CS A and AB exams.

Method Summary

E	get(Location loc) Returns the object at a given location in this grid.
ArrayList<Location>	getEmptyAdjacentLocations(Location loc) Gets the valid empty locations adjacent to a given location in all eight compass directions (north, northeast, east, southeast, south, southwest, west, and northwest).
ArrayList<E>	getNeighbors(Location loc) Gets the neighboring occupants in all eight compass directions (north, northeast, east, southeast, south, southwest, west, and northwest).
int	getNumCols() Returns the number of columns in this grid.
int	getNumRows() Returns the number of rows in this grid.
ArrayList<Location>	getOccupiedAdjacentLocations(Location loc) Gets the valid occupied locations adjacent to a given location in all eight compass directions (north, northeast, east, southeast, south, southwest, west, and northwest).
ArrayList<Location>	getOccupiedLocations() Gets the locations in this grid that contain objects.
ArrayList<Location>	getValidAdjacentLocations(Location loc) Gets the valid locations adjacent to a given location in all eight compass directions (north, northeast, east, southeast, south, southwest, west, and northwest).
boolean	isValid(Location loc) Checks whether a location is valid in this grid.
E	put(Location loc, E obj) Puts an object at a given location in this grid.
E	remove(Location loc) Removes the object at a given location from this grid.

Method Detail

getNumRows

int getNumRows()

Returns the number of rows in this grid.

Returns:

the number of rows, or -1 if this grid is unbounded

getNumCols

int getNumCols()

Returns the number of columns in this grid.

Returns:

the number of columns, or -1 if this grid is unbounded

isValid

boolean isValid(Location loc)

Checks whether a location is valid in this grid.
Precondition: loc is not null

Parameters:

loc - the location to check

Returns:

true if loc is valid in this grid, false otherwise

put

E put(Location loc,
      E obj)

Puts an object at a given location in this grid.
Precondition: (1) loc is valid in this grid (2) obj is not null

Parameters:

loc - the location at which to put the object

obj - the new object to be added

Returns:

the object previously at loc (or null if the location was previously unoccupied)

remove

E remove(Location loc)

Removes the object at a given location from this grid.
Precondition: loc is valid in this grid

Parameters:

loc - the location of the object that is to be removed

Returns:

the object that was removed (or null if the location is unoccupied)

get

E get(Location loc)

Returns the object at a given location in this grid.
Precondition: loc is valid in this grid

Parameters:

loc - a location in this grid

Returns:

the object at location loc (or null if the location is unoccupied)

getOccupiedLocations

ArrayList<Location> getOccupiedLocations()

Gets the locations in this grid that contain objects.

Returns:

an array list of all occupied locations in this grid

getValidAdjacentLocations

ArrayList<Location> getValidAdjacentLocations(Location loc)

Gets the valid locations adjacent to a given location in all eight compass directions (north, northeast, east, southeast, south, southwest, west, and northwest).
Precondition: loc is valid in this grid

Parameters:

loc - a location in this grid

Returns:

an array list of the valid locations adjacent to loc in this grid

getEmptyAdjacentLocations

ArrayList<Location> getEmptyAdjacentLocations(Location loc)

Gets the valid empty locations adjacent to a given location in all eight compass directions (north, northeast, east, southeast, south, southwest, west, and northwest).
Precondition: loc is valid in this grid

Parameters:

loc - a location in this grid

Returns:

an array list of the valid empty locations adjacent to loc in this grid

getOccupiedAdjacentLocations

ArrayList<Location> getOccupiedAdjacentLocations(Location loc)

Gets the valid occupied locations adjacent to a given location in all eight compass directions (north, northeast, east, southeast, south, southwest, west, and northwest).
Precondition: loc is valid in this grid

Parameters:

loc - a location in this grid

Returns:

an array list of the valid occupied locations adjacent to loc in this grid

getNeighbors

ArrayList<E> getNeighbors(Location loc)

Gets the neighboring occupants in all eight compass directions (north, northeast, east, southeast, south, southwest, west, and northwest).
Precondition: loc is valid in this grid

Parameters:

loc - a location in this grid

Returns:

returns an array list of the objects in the occupied locations adjacent to loc in this grid