Package nl.bebr.mapviewer.data

Class TileCache<T>

  • public abstract class TileCache<T>
extends Object
    An implementation only class for now. For internal use only.
    Author:
    joshua.marinacci@sun.com, Frantisek Post

    • Constructor Detail

      • TileCache

        public TileCache()

    • Method Detail

      • put

        public void put​(URI uri,
                T img)
        Put a tile image into the cache. This puts both a buffered image and array of bytes that make up the compressed image.
        Parameters:
        uri - URI of image that is being stored in the cache
        img - image to store in the cache

      • get

        public T get​(URI uri)
      throws IOException
        Returns a buffered image for the requested URI from the cache. This method must return null if the image is not in the cache. If the image is unavailable but it's compressed version *is* available, then the compressed version will be expanded and returned.
        Parameters:
        uri - URI of the image previously put in the cache
        Returns:
        the image matching the requested URI, or null if not available
        Throws:
        IOException

      • getImageSizeInBytes

        protected abstract int getImageSizeInBytes​(T image)

      • getImgMap

        protected abstract Map<URI,​T> getImgMap()
        target implementation should return static imageMap
        Returns:

      • needMoreMemory

        public void needMoreMemory()
        Request that the cache free up some memory. How this happens or how much memory is freed is up to the TileCache implementation. Subclasses can implement their own strategy. The default strategy is to clear out all buffered images but retain the compressed versions.

      • clear

        public void clear()