nankin.zheng.gatem.model
Class GameContainer

java.lang.Object
  |
  +--nankin.zheng.gatem.model.GameContainer

public abstract class GameContainer

extends java.lang.Object

GameContainer is in charge of the game (frame) updating and the communications among all the roles inside it. All the work is done by a thread while game is not over. NOTE that by default, GameContainer does not care about user input.

Version:

1.0, Date 2003-04-11

Author:

ZHENG Zhong

Field Summary

protected Background	background A background reference is held seperately to update viewport.
protected Env	env The game environment.
protected StageLoader	loader Stage loader, which loads stage information (creates RoleView and Role objects) for this container.
protected java.util.Vector	roleList Role list, containing all the active roles whose act() will be called during every frame-updating.
protected GameScheduler	scheduler Game scheduler, which schedules all the game containers.
protected int	status Status of the container.

Constructor Summary

GameContainer(Env environ)
Constructor.

Method Summary

void	addRole(Role r) Add a new role into the role list.
void	broadcastGameEvent(GameEvent gevt) Broadcast a game event to all the roles in the roleList.
protected void	drawGameFrame() This method draws all the roles onto the screen without changing their status.
int	getContainerStatus() Get container status.
StageLoader	getStageLoader() Get stage loader for this container.
protected abstract void	receiveGameEvent(GameEvent gevt) This method works as Role.receiveGameEvent(...) since game event may also have some impact on GameContainer.
void	setBackground(Background b) Sets background.
void	setContainerStatus(int sts) Set container status.
void	setGameScheduler(GameScheduler s) Set game scheduler.
void	setStageLoader(StageLoader l) Set stage loader for this container.
void	testInitialization() Verify whether this object is initialized properly.
void	unloadStage() Unload this stage.
void	updateGameFrame() This method updates all the roles' logical status.

Methods inherited from class java.lang.Object

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

Field Detail

env

protected Env env

The game environment.

scheduler

protected GameScheduler scheduler

Game scheduler, which schedules all the game containers.

status

protected int status

Status of the container. Constants of container status are defined in class GameScheduler.

background

protected Background background

A background reference is held seperately to update viewport.

roleList

protected java.util.Vector roleList

Role list, containing all the active roles whose act() will be called during every frame-updating.

loader

protected StageLoader loader

Stage loader, which loads stage information (creates RoleView and Role objects) for this container.

Constructor Detail

GameContainer

public GameContainer(Env environ)
              throws GameException

Constructor.

Parameters:

environ - game environment

Throws:

java.lang.NullPointerException - if environ is null.

GameException - if any error occured.

Method Detail

setBackground

public void setBackground(Background b)
                   throws GameException

Sets background.

The specified Background b should be a Role object, and should have already been added in the roleList.

Parameters:

b - background

Throws:

GameException - if b is not in the roleList yet.

getContainerStatus

public int getContainerStatus()

Get container status.

Returns:

status of GameContainer.

setContainerStatus

public void setContainerStatus(int sts)

Set container status.

Parameters:

sts - status of GameContainer.

setGameScheduler

public void setGameScheduler(GameScheduler s)

Set game scheduler.

Parameters:

s - game scheduler.

addRole

public void addRole(Role r)
             throws java.lang.NullPointerException

Add a new role into the role list.

Parameters:

r - role

Throws:

java.lang.NullPointerException - if r is null.

testInitialization

public void testInitialization()
                        throws GameException

Verify whether this object is initialized properly.

This method should be overridden to provide more strict verification.

NOTE that this method will call all the roles' testInitialization(), which means that the roles' proper initailization is the necessary condition of its proper initialization.

Throws:

GameException - if this GameContainer is not initialized properly.

updateGameFrame

public void updateGameFrame()
                     throws GameException

This method updates all the roles' logical status.

Throws:

GameException - may be thrown out by Role.act().

drawGameFrame

protected void drawGameFrame()
                      throws GameException

This method draws all the roles onto the screen without changing their status.

Throws:

GameException - may be thrown out by Role.draw().

broadcastGameEvent

public void broadcastGameEvent(GameEvent gevt)
                        throws GameException

Broadcast a game event to all the roles in the roleList.

This method is called by a role who fires a GameEvent. It will do the following two things:

• broadcast the GameEvent to every role in the roleList
• decide whether this event has an impact on itself

Parameters:

gevt - game event to be broadcast.

Throws:

GameException - may be thrown out by receiveGameEvent().

receiveGameEvent

protected abstract void receiveGameEvent(GameEvent gevt)
                                  throws GameException

This method works as Role.receiveGameEvent(...) since game event may also have some impact on GameContainer.

Parameters:

gevt - game event.

Throws:

GameException - may be thrown out by its subclasses.

setStageLoader

public void setStageLoader(StageLoader l)

Set stage loader for this container.

Parameters:

l - stage loader.

getStageLoader

public StageLoader getStageLoader()

Get stage loader for this container.

Returns:

stage loader.

unloadStage

public void unloadStage()

Unload this stage.

This method will clean its role list and unset its background, and then run System.gc(). This work will be done before a new stage is loaded.