com.yospace.yae.yogi
Class NativeResources

java.lang.Object
  |
  +--com.yospace.yae.yogi.NativeResources

Direct Known Subclasses:

MIDletResources

public abstract class NativeResources

extends java.lang.Object

The controller and access point for the native resources needed by YAE and YoGI.

It may be assumed that this class and its subclasses are completely constructed before any other Toolkit or YogiRootPane subsystems are alive. Thus, it is important that no complex YoGI operations are invoked during the construction phase of this class, as they may not yet be initialized.

Constructor Summary

protected

NativeResources() Constructor is protected so that NativeResources displays singleton characteristics.

Method Summary

abstract Image	createImage(byte[] imageData, int imageOffset, int imageLength) Creates an immutable native image which is decoded from the data stored in the specified byte array at the specified offset and length.
abstract Image	createImage(Image source) Creates an immutable image from a source image.
abstract Image	createImage(java.lang.String name) Creates an immutable image from decoded image data obtained from the named resource.
abstract Font	createNativeFont(int face, int style, int size) Creates a MIDP Font given a typeface, style and size.
static NativeResources	get() Accessor method that gets the current NativeResources object.
abstract int	getCanvasHeight() Gets the canvas height.
abstract int	getCanvasWidth() Gets the canvas width.
static javax.microedition.lcdui.Display	getDisplay() Convenience method for getting the MIDP Display of the current NativeResources object.
protected abstract javax.microedition.lcdui.Display	getDisplayImpl() Template method for accessing the Display.
static Graphics	getGraphics() Convenience method for getting the Graphics of the current NativeResources object.
protected abstract Graphics	getGraphicsImpl() Template method for accessing the Graphics.
abstract java.lang.String	getProperty(java.lang.String propName) Gets the named property supplied in the Panelet URL.
abstract java.lang.String	getSystemProperty(java.lang.String name) Template method for accessing system properties.
void	grabResources(java.lang.Object key) Tells us that it is time to grab heavy resources, as YoGI is now online.
protected void	grabResourcesImpl() Template method for grabbing native resources.
abstract void	repaint() Requests a repaint of the whole canvas.
abstract void	repaint(int x, int y, int width, int height) Requests a repaint of a rectangular area of the canvas.
abstract void	serviceRepaints() Forces all pending repaints to be completed immediately.
static void	set(NativeResources ynr) Sets the NativeResources to be ynr.
static void	setKey(java.lang.Object theKey) Sets up the key to validate resource grabbing and trimming reation requests against.
void	trimResources(java.lang.Object key) Tells us that it is time to lose any heavy resources as the Panelet system is idle.
protected void	trimResourcesImpl() Template method for trimming native resources.

Methods inherited from class java.lang.Object

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

Constructor Detail

NativeResources

protected NativeResources()

Constructor is protected so that NativeResources displays singleton characteristics.

Method Detail

set

public static void set(NativeResources ynr)

Sets the NativeResources to be ynr.

Parameters:

ynr - the NativeResources to be used.

setKey

public static final void setKey(java.lang.Object theKey)

Sets up the key to validate resource grabbing and trimming reation requests against. Can only be performed once per 'run' of the VM.

Parameters:

theKey - the key to use.

get

public static NativeResources get()

Accessor method that gets the current NativeResources object.

Returns:

the current NativeResources.

getGraphics

public static Graphics getGraphics()

Convenience method for getting the Graphics of the current NativeResources object. Calls getGraphicsImpl().

Returns:

the current Graphics.

getDisplay

public static javax.microedition.lcdui.Display getDisplay()

Convenience method for getting the MIDP Display of the current NativeResources object. Calls getDisplayImpl().

Returns:

the current MIDP Display.

getGraphicsImpl

protected abstract Graphics getGraphicsImpl()

Template method for accessing the Graphics.

getDisplayImpl

protected abstract javax.microedition.lcdui.Display getDisplayImpl()

Template method for accessing the Display.

getSystemProperty

public abstract java.lang.String getSystemProperty(java.lang.String name)

Template method for accessing system properties.

Parameters:

name - the name of the requested property.

Returns:

the corresponding property value.

Throws:

NullPointerException - if there is no such property.

trimResources

public final void trimResources(java.lang.Object key)

Tells us that it is time to lose any heavy resources as the Panelet system is idle. Stop threads, remove canvases, lose weight.

Calls trimResourcesImpl() if the key is valid.

Parameters:

key - the key for the NativeResources.

trimResourcesImpl

protected void trimResourcesImpl()

Template method for trimming native resources.

grabResources

public final void grabResources(java.lang.Object key)

Tells us that it is time to grab heavy resources, as YoGI is now online. In particular, we should restart anything that we dumped if trimResources() was called.

Calls grabResourcesImpl() if the key is valid.

Parameters:

key - the key for the NativeResources.

grabResourcesImpl

protected void grabResourcesImpl()

Template method for grabbing native resources.

getCanvasWidth

public abstract int getCanvasWidth()

Gets the canvas width.

Returns:

the canvas width.

getCanvasHeight

public abstract int getCanvasHeight()

Gets the canvas height.

Returns:

the canvas height.

repaint

public abstract void repaint()

Requests a repaint of the whole canvas.

repaint

public abstract void repaint(int x,
                             int y,
                             int width,
                             int height)

Requests a repaint of a rectangular area of the canvas.

Parameters:

x - the x coordinate of the top-left corner of the rectangle.

y - the y coordinate of the top-left corner of the rectangle.

width - the width of the rectangle.

height - the height of the rectangle.

serviceRepaints

public abstract void serviceRepaints()

Forces all pending repaints to be completed immediately.

createNativeFont

public abstract Font createNativeFont(int face,
                                      int style,
                                      int size)

Creates a MIDP Font given a typeface, style and size.

Parameters:

face - the typeface of the font.

style - the style of the font.

size - the size of the font.

See Also:

Font

createImage

public abstract Image createImage(byte[] imageData,
                                  int imageOffset,
                                  int imageLength)

Creates an immutable native image which is decoded from the data stored in the specified byte array at the specified offset and length. A yogi image is then created based on this native image.

Parameters:

imageData - the array of image data in a supported image format

imageOffset - the offset of the start of the data in the array

imageLength - the length of the data in the array

Returns:

a new YoGI Image if creation of the native Image was successful

createImage

public abstract Image createImage(Image source)

Creates an immutable image from a source image.

Parameters:

source - the source image to be copied.

Returns:

the new, immutable YoGI Image.

createImage

public abstract Image createImage(java.lang.String name)

Creates an immutable image from decoded image data obtained from the named resource.

Parameters:

name - the name of the resource containing the image data in one of the supported image formats

Returns:

a new YoGI Image if creation of the native Image was successful

getProperty

public abstract java.lang.String getProperty(java.lang.String propName)

Gets the named property supplied in the Panelet URL.

Parameters:

propName - name of the required property.

Returns:

the relevant property value.