com.sun.sgs.example.hack.server.level

Class SimpleBoard

java.lang.Object

com.sun.sgs.example.hack.server.level.SimpleBoard

All Implemented Interfaces:

LevelBoard, Board, Serializable

public class SimpleBoard
extends Object
implements LevelBoard

A server-side LevelBoard implementation that utilizes individual tile-locking to achieve maximum concurrency. Internally, the board is represented as a 2D gride of tiles, each of which are ManagedObject instances. Accesses and updates only acquire the minimum number of tiles, which results in better througput for a board with many active players. This implementation uses a ScalableHashMap of points instead of a ManagedReference<Tile>[][] to store its tiles in order to reduce the amount of data that needs to be loaded for each board access. For large boards, the ManagedReference array would have imposed a significant data bottleneck.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface com.sun.sgs.example.hack.server.level.LevelBoard

LevelBoard.ActionResult

Constructor Summary

Constructors

Constructor and Description
SimpleBoard(int width, int height) Creates a new instance of SimpleBoard with an empty tile set

Method Summary

Methods

Modifier and Type	Method and Description
boolean	addCharacterAt(int x, int y, CharacterManager mgr) Tries to add a character at the given location.
boolean	addItemAt(int x, int y, Item item) Tries to add an item at the given location.
int[]	getAt(int x, int y) Returns the stack of identifiers at the given position.
int	getHeight() Returns the height of this board.
LevelBoard.ActionResult	getItem(int x, int y, CharacterManager mgr) Tries to take an item on this tile.
int	getWidth() Returns the width of this board.
boolean	isDark() Returns whether or not this board is dark.
LevelBoard.ActionResult	moveTo(int x, int y, CharacterManager mgr) Moves the given character to the given location.
static SimpleBoard	parse(StreamTokenizer stok, Set<Integer> impassableSprites) Creates a new instance of SimpleBoard from the given tokenized stream.
boolean	removeCharacterAt(int x, int y, CharacterManager mgr) Tries to remove a character from the given location.
boolean	removeItemAt(int x, int y, Item item) Tries to remove an item from the given location.
void	setAsConnector(int x, int y, Connector connector) Sets the given space as a connector.
boolean	testMove(int x, int y, CharacterManager mgr) Tests to see if a move would be possible to the given location for the given character.

Methods inherited from class java.lang.Object

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

Constructor Detail

SimpleBoard

public SimpleBoard(int width,
           int height)

Creates a new instance of SimpleBoard with an empty tile set

Parameters:

width - the width of the board

height - the height of the board

Throws:

IllegalArgumentException - if height or width is non-positive

Method Detail

parse

public static SimpleBoard parse(StreamTokenizer stok,
                Set<Integer> impassableSprites)
                         throws IOException

Creates a new instance of SimpleBoard from the given tokenized stream.

Parameters:

stok - a StreamTokenizer that provides the board

impassableSprites - the set of identifiers that are impassable

Throws:

IOException - if the stream isn't formatted correctly

setAsConnector

public void setAsConnector(int x,
                  int y,
                  Connector connector)

Sets the given space as a connector.

Parameters:

x - the x-coordinate

y - the y-coordinate

connector - the Connector

getWidth

public int getWidth()

Returns the width of this board.

Specified by:

getWidth in interface Board

Returns:

the board's width

getHeight

public int getHeight()

Returns the height of this board.

Specified by:

getHeight in interface Board

Returns:

the board's height

getAt

public int[] getAt(int x,
          int y)

Returns the stack of identifiers at the given position.

Specified by:

getAt in interface Board

Parameters:

x - the x-coordinate

y - the y-coordinate

Returns:

the set of identifiers at this space

isDark

public boolean isDark()

Returns whether or not this board is dark.

Specified by:

isDark in interface Board

Returns:

true if this board is dark, false otherwise

addCharacterAt

public boolean addCharacterAt(int x,
                     int y,
                     CharacterManager mgr)

Tries to add a character at the given location. This board only allows one character per space.

Specified by:

addCharacterAt in interface LevelBoard

Parameters:

x - the x-coordinate

y - the y-coordinate

mgr - the character's manager

Returns:

true if the operation succeeded, false otherwise

removeCharacterAt

public boolean removeCharacterAt(int x,
                        int y,
                        CharacterManager mgr)

Tries to remove a character from the given location.

Specified by:

removeCharacterAt in interface LevelBoard

Parameters:

x - the x-coordinate

y - the y-coordinate

mgr - the character's manager

Returns:

true if the operation succeeded, false otherwise

addItemAt

public boolean addItemAt(int x,
                int y,
                Item item)

Tries to add an item at the given location. This board only allows one item per space.

Specified by:

addItemAt in interface LevelBoard

Parameters:

x - the x-coordinate

y - the y-coordinate

item - the item's manager

Returns:

true if the operation succeeded, false otherwise

removeItemAt

public boolean removeItemAt(int x,
                   int y,
                   Item item)

Tries to remove an item from the given location.

Specified by:

removeItemAt in interface LevelBoard

Parameters:

x - the x-coordinate

y - the y-coordinate

item - the item's manager

Returns:

true if the operation succeeded, false otherwise

testMove

public boolean testMove(int x,
               int y,
               CharacterManager mgr)

Tests to see if a move would be possible to the given location for the given character.

Specified by:

testMove in interface LevelBoard

Parameters:

x - the x-coordinate

y - the y-coordinate

mgr - the character's manager

Returns:

true if the operation would succeed, false otherwise

moveTo

public LevelBoard.ActionResult moveTo(int x,
                             int y,
                             CharacterManager mgr)

Moves the given character to the given location. The character must alredy be on the board through a call to addCharacterAt.

Specified by:

moveTo in interface LevelBoard

Parameters:

x - the x-coordinate

y - the y-coordinate

mgr - the character's manager

Returns:

the result of attempting the move

getItem

public LevelBoard.ActionResult getItem(int x,
                              int y,
                              CharacterManager mgr)

Tries to take an item on this tile. Unlike moveTo, this actually will remove items from the tile if they are successfully taken.

Specified by:

getItem in interface LevelBoard

Parameters:

mgr - the manager for a character

x - the x-coordinate

y - the y-coordinate

Returns:

the result of getting an item