java.awt

Class Component.FlipBufferStrategy

protected class Component.FlipBufferStrategy extends BufferStrategy

This class provides support for flipping component buffers. It can only be used on Canvases and Windows.

Since: 1.4

Field Summary
protected BufferCapabilities	caps The capabilities of this buffering strategy.
protected Image	drawBuffer An Image reference to the drawing buffer.
protected VolatileImage	drawVBuffer A VolatileImage reference to the drawing buffer.
protected int	numBuffers The number of buffers.
protected boolean	validatedContents Whether or not the image buffer resources are allocated and ready to be drawn into.

Constructor Summary
protected	FlipBufferStrategy(int numBuffers, BufferCapabilities caps) Creates a flipping buffer strategy.

Method Summary
boolean	contentsLost() Returns whether or not the image buffer resources have been lost.
boolean	contentsRestored() Returns whether or not the image buffer resources have been restored.
protected void	createBuffers(int numBuffers, BufferCapabilities caps) Creates a multi-buffer flipping strategy.
protected void	destroyBuffers() Release the back buffer's resources.
protected void	flip(BufferCapabilities.FlipContents flipAction) Perform a flip operation to transfer the contents of the back buffer to the front buffer.
protected Image	getBackBuffer() Return a direct reference to the back buffer image.
BufferCapabilities	getCapabilities() Retrieves the capabilities of this buffer strategy.
Graphics	getDrawGraphics() Retrieves a graphics object that can be used to draw into this strategy's image buffer.
protected void	revalidate() Re-create the image buffer resources if they've been lost.
void	show() Bring the contents of the back buffer to the front buffer.

Field Detail

caps

protected BufferCapabilities caps

The capabilities of this buffering strategy.

drawBuffer

protected Image drawBuffer

An Image reference to the drawing buffer.

drawVBuffer

protected VolatileImage drawVBuffer

A VolatileImage reference to the drawing buffer.

numBuffers

protected int numBuffers

The number of buffers.

validatedContents

protected boolean validatedContents

Whether or not the image buffer resources are allocated and ready to be drawn into.

Constructor Detail

FlipBufferStrategy

protected FlipBufferStrategy(int numBuffers, BufferCapabilities caps)

Creates a flipping buffer strategy. The only supported strategy for FlipBufferStrategy itself is a double-buffer page flipping strategy. It forms the basis for more complex derived strategies.

Parameters: numBuffers the number of buffers caps the capabilities of this buffering strategy

Throws: AWTException if the requested number-of-buffers/capabilities combination is not supported

Method Detail

contentsLost

public boolean contentsLost()

Returns whether or not the image buffer resources have been lost.

Returns: true if the resources have been lost, false otherwise

contentsRestored

public boolean contentsRestored()

Returns whether or not the image buffer resources have been restored.

Returns: true if the resources have been restored, false otherwise

createBuffers

protected void createBuffers(int numBuffers, BufferCapabilities caps)

Creates a multi-buffer flipping strategy. The number of buffers must be greater than one and the buffer capabilities must specify page flipping.

Parameters: numBuffers the number of flipping buffers; must be greater than one caps the buffering capabilities; caps.isPageFlipping() must return true

Throws: IllegalArgumentException if numBuffers is not greater than one or if the page flipping capability is not requested AWTException if the requested flipping strategy is not supported

Returns: a direct reference to the back buffer image.

getCapabilities

public BufferCapabilities getCapabilities()

Retrieves the capabilities of this buffer strategy.

Returns: the capabilities of this buffer strategy

getDrawGraphics

public Graphics getDrawGraphics()

Retrieves a graphics object that can be used to draw into this strategy's image buffer.

Returns: a graphics object

revalidate

protected void revalidate()

Re-create the image buffer resources if they've been lost.

show

public void show()

Bring the contents of the back buffer to the front buffer.