Module java.desktop
Package java.awt

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

    Fields
    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

    Constructors
    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 getDrawGraphics.
    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 BufferStrategy and removes it from the associated Component.
    BufferCapabilities
    getCapabilities()
    Returns the BufferCapabilities for this BufferStrategy.
    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 Details

    • 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 Details

    • 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 Details

    • 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 class BufferStrategy
      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 class BufferStrategy
      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 class BufferStrategy
      Returns:
      the draw graphics

    • show

      public void show()
      Makes the next available buffer visible.
      Specified by:
      show in class BufferStrategy

    • 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 class BufferStrategy
      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 class BufferStrategy
      Returns:
      whether the drawing buffer was recently restored from a lost state and reinitialized to the default background color (white)
      See Also:
      VolatileImage