Class Component.BltBufferStrategy
- java.lang.Object
-
- java.awt.image.BufferStrategy
-
- java.awt.Component.BltBufferStrategy
- Enclosing class:
- Component
protected class Component.BltBufferStrategy extends BufferStrategy
Inner class for blitting offscreen surfaces to a component.
- Since:
- 1.4
Field Summary
Modifier and Type | Field | Description |
---|---|---|
protected VolatileImage[] | backBuffers | The back buffers |
protected BufferCapabilities | caps | The buffering capabilities |
protected int | height | Height of the back buffers |
protected boolean | validatedContents | Whether or not the drawing buffer has been recently restored from a lost state. |
protected int | width | Width of the back buffers |
Constructor Summary
Modifier | Constructor | Description |
---|---|---|
protected | BltBufferStrategy(int numBuffers,
BufferCapabilities caps) | Creates a new blt buffer strategy around a component |
Method Summary
Modifier and Type | Method | Description |
---|---|---|
boolean | contentsLost() | Returns whether the drawing buffer was lost since the last call to |
boolean | contentsRestored() | Returns whether the drawing buffer was recently restored from a lost state and reinitialized to the default background color (white). |
protected void | createBackBuffers(int numBuffers) | Creates the back buffers |
void | dispose() | Releases system resources currently consumed by this |
BufferCapabilities | getCapabilities() | Returns the |
Graphics | getDrawGraphics() | Creates a graphics context for the drawing buffer. |
protected void | revalidate() | Restore the drawing buffer if it has been lost |
void | show() | Makes the next available buffer visible. |
Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Field Detail
caps
protected BufferCapabilities caps
The buffering capabilities
backBuffers
protected VolatileImage[] backBuffers
The back buffers
validatedContents
protected boolean validatedContents
Whether or not the drawing buffer has been recently restored from a lost state.
width
protected int width
Width of the back buffers
height
protected int height
Height of the back buffers
Constructor Detail
BltBufferStrategy
protected BltBufferStrategy(int numBuffers, BufferCapabilities caps)
Creates a new blt buffer strategy around a component
- Parameters:
-
numBuffers
- number of buffers to create, including the front buffer -
caps
- the capabilities of the buffers
Method Detail
dispose
public void dispose()
Releases system resources currently consumed by this BufferStrategy
and removes it from the associated Component. After invoking this method, getBufferStrategy
will return null. Trying to use a BufferStrategy
after it has been disposed will result in undefined behavior.
- Overrides:
-
dispose
in classBufferStrategy
- Since:
- 1.6
- See Also:
-
Window.createBufferStrategy(int)
,Canvas.createBufferStrategy(int)
,Window.getBufferStrategy()
,Canvas.getBufferStrategy()
createBackBuffers
protected void createBackBuffers(int numBuffers)
Creates the back buffers
- Parameters:
-
numBuffers
- the number of buffers to create
getCapabilities
public BufferCapabilities getCapabilities()
Description copied from class: BufferStrategy
Returns the BufferCapabilities
for this BufferStrategy
.
- Specified by:
-
getCapabilities
in classBufferStrategy
- Returns:
- the buffering capabilities of this strategy
getDrawGraphics
public Graphics getDrawGraphics()
Description copied from class: BufferStrategy
Creates a graphics context for the drawing buffer. This method may not be synchronized for performance reasons; use of this method by multiple threads should be handled at the application level. Disposal of the graphics object obtained must be handled by the application.
- Specified by:
-
getDrawGraphics
in classBufferStrategy
- Returns:
- the draw graphics
show
public void show()
Makes the next available buffer visible.
- Specified by:
-
show
in classBufferStrategy
revalidate
protected void revalidate()
Restore the drawing buffer if it has been lost
contentsLost
public boolean contentsLost()
Description copied from class: BufferStrategy
Returns whether the drawing buffer was lost since the last call to getDrawGraphics
. Since the buffers in a buffer strategy are usually type VolatileImage
, they may become lost. For a discussion on lost buffers, see VolatileImage
.
- Specified by:
-
contentsLost
in classBufferStrategy
- Returns:
- whether the drawing buffer was lost since the last call to
getDrawGraphics
- See Also:
VolatileImage
contentsRestored
public boolean contentsRestored()
Description copied from class: BufferStrategy
Returns whether the drawing buffer was recently restored from a lost state and reinitialized to the default background color (white). Since the buffers in a buffer strategy are usually type VolatileImage
, they may become lost. If a surface has been recently restored from a lost state since the last call to getDrawGraphics
, it may require repainting. For a discussion on lost buffers, see VolatileImage
.
- Specified by:
-
contentsRestored
in classBufferStrategy
- Returns:
- whether the drawing buffer was recently restored from a lost state and reinitialized to the default background color (white)
- See Also:
VolatileImage