Module java.desktop
Package java.awt

Class Component.BltBufferStrategy

  • Enclosing class:
    Component


    protected class Component.BltBufferStrategy
    extends BufferStrategy
    Inner class for blitting offscreen surfaces to a component.
    Since:
    1.4
    • Field Detail

      • 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

      • createBackBuffers

        protected void createBackBuffers​(int numBuffers)
        Creates the back buffers
        Parameters:
        numBuffers - the number of buffers to create
      • 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