com.collegeboard.gridworld.actor
Class AbstractCritter

java.lang.Object
  com.collegeboard.gridworld.actor.Actor
      com.collegeboard.gridworld.actor.AbstractCritter

Direct Known Subclasses:

SimpleCritter

public abstract class AbstractCritter
extends Actor

A critter is an actor that moves through its world, processing its neighbors in some way and then picking a new location.

copyright© 2005 Cay S. Horstmann (http://horstmann.com)

Author:

Cay Horstmann

Constructor Summary

AbstractCritter()

Method Summary

void	act() A critter acts by getting a list of its neighbors, processing them, getting locations to move to, selecting one of them, and moving to the selected location.
abstract ArrayList<Location>	getMoveLocations() Get the possible locations for the next move.
abstract ArrayList<Actor>	getNeighbors() Get the neighbors for processing.
abstract void	makeMove(Location loc) Moves this critter to the given location.
abstract void	processNeighbors(ArrayList<Actor> neighbors) Process the critter's neighbors.
abstract Location	selectMoveLocation(ArrayList<Location> locs) Selects the location for the next move.

Methods inherited from class com.collegeboard.gridworld.actor.Actor

getColor, getDirection, getGrid, getLocation, moveTo, putSelfInGrid, removeSelfFromGrid, setColor, setDirection, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractCritter

public AbstractCritter()

Method Detail

act

public void act()

A critter acts by getting a list of its neighbors, processing them, getting locations to move to, selecting one of them, and moving to the selected location.

Specified by:

act in class Actor

getNeighbors

public abstract ArrayList<Actor> getNeighbors()

Get the neighbors for processing. Implemented to return the actors that occupy neighboring grid locations. Override this method for subclasses that look elsewhere for neighbors.

Returns:

a list of actors that are neighbors of this critter

processNeighbors

public abstract void processNeighbors(ArrayList<Actor> neighbors)

Process the critter's neighbors. This method is implemented to do nothing. Override it in subclasses that process neighbors, for example by examining or removing them.

Parameters:

neighbors - the neighbors to be processed

getMoveLocations

public abstract ArrayList<Location> getMoveLocations()

Get the possible locations for the next move. Implemented to return the empty neighboring locations. Override this method for subclasses that look elsewhere for move locations.

Returns:

a list of possible locations for the next move

selectMoveLocation

public abstract Location selectMoveLocation(ArrayList<Location> locs)

Selects the location for the next move. Implemented to randomly pick one of the possible locations, or to return the current location if locs has size 0. Override this method for subclasses that have another mechanism for selecting the next move location.

Parameters:

locs - the possible locations for the next move

Returns:

the location that was selected for the next move.

makeMove

public abstract void makeMove(Location loc)

Moves this critter to the given location. Implemented to call moveTo. Override this method for subclasses that want to carry out other actions for moving (for example, turning or leaving traces).

Parameters:

loc - the location to move to (must be valid)