Draft cache interfaces

src/main/java/bdv/cache/CacheInterfaces.java

+package bdv.cache;
+
+import java.util.concurrent.ExecutionException;
+
+public class CacheInterfaces
+{
+	public interface CacheLoader< K, V >
+	{
+		V get( K key ) throws Exception;
+	}
+
+	public interface RemovalListener< K, V >
+	{
+		void onRemoval( K key, V value );
+	}
+
+	public interface AbstractCache< K, V >
+	{
+		V getIfPresent( K key );
+
+		void invalidateAll();
+//		void cleanUp();
+//		void invalidate( Object key );
+//		long size();
+	}
+
+	public interface Cache< K, V > extends AbstractCache< K, V >
+	{
+		V get(
+				K key,
+				CacheLoader< ? super K, ? extends V > loader ) throws ExecutionException;
+	}
+
+	public interface LoadingCache< K, V > extends AbstractCache< K, V >, CacheLoader< K, V >
+	{
+		@Override
+		V get( K key ) throws ExecutionException;
+	}
+
+	public interface ListenableCache< K, V > extends AbstractCache< K, V >
+	{
+		V get(
+				K key,
+				CacheLoader< ? super K, ? extends V > loader,
+				RemovalListener< ? super K, ? super V > remover ) throws ExecutionException;
+	}
+
+	public interface ListenableLoadingCache< K, V > extends AbstractCache< K, V >
+	{
+		V get(
+				K key,
+				RemovalListener< ? super K, ? super V > remover ) throws ExecutionException;
+	}
+
+	/*
+	 * Volatile
+	 */
+
+	public interface VolatileCacheLoader< K, V > extends CacheLoader< K, V >
+	{
+		public V createInvalid( K key ) throws Exception;
+	}
+
+	public interface AbstractVolatileCache< K, V >
+	{
+		V getIfPresent(
+				K key,
+				CacheHints cacheHints ) throws ExecutionException;
+
+		void invalidateAll();
+//		void cleanUp();
+//		void invalidate( Object key );
+//		long size();
+	}
+
+	public interface VolatileCache< K, V > extends AbstractVolatileCache< K, V >
+	{
+		V get(
+				K key,
+				VolatileCacheLoader< ? super K, ? extends V > loader,
+				CacheHints cacheHints ) throws ExecutionException;
+	}
+
+	public interface VolatileLoadingCache< K, V > extends AbstractVolatileCache< K, V >
+	{
+		V get(
+				K key,
+				CacheHints cacheHints ) throws ExecutionException;
+	}
+
+	public interface VolatileListenableCache< K, V > extends AbstractVolatileCache< K, V >
+	{
+		V get(
+				K key,
+				VolatileCacheLoader< ? super K, ? extends V > loader,
+				RemovalListener< ? super K, ? super V > remover,
+				CacheHints cacheHints ) throws ExecutionException;
+	}
+
+	public interface VolatileListenableLoadingCache< K, V > extends VolatileListenableCache< K, V >, VolatileLoadingCache< K, V >
+	{
+		V get(
+				K key,
+				RemovalListener< ? super K, ? super V > remover,
+				CacheHints cacheHints ) throws ExecutionException;
+	}
+
+	/*
+	 * Adapters that translate keys.
+	 */
+
+	public interface KeyBimap< K, L >
+	{
+		L getTarget( K key );
+
+		K getSource( L key );
+	}
+
+	public static class AbstractCacheAdapter< K, L, V, C extends AbstractCache< L, V > >
+			implements AbstractCache< K, V >
+	{
+		protected final C cache;
+
+		protected final KeyBimap< K, L > keymap;
+
+		public AbstractCacheAdapter( final C cache, final KeyBimap< K, L > keymap )
+		{
+			this.cache = cache;
+			this.keymap = keymap;
+		}
+
+		@Override
+		public V getIfPresent( final K key )
+		{
+			return cache.getIfPresent( keymap.getTarget( key ) );
+		}
+
+		@Override
+		public void invalidateAll()
+		{
+			cache.invalidateAll();
+		}
+	}
+
+	public static class CacheAdapter< K, L, V, C extends Cache< L, V > >
+			extends AbstractCacheAdapter< K, L, V, C >
+			implements Cache< K, V >
+	{
+		public CacheAdapter( final C cache, final KeyBimap< K, L > keymap )
+		{
+			super( cache, keymap );
+		}
+
+		@Override
+		public V get( final K key, final CacheLoader< ? super K, ? extends V > loader ) throws ExecutionException
+		{
+			return cache.get(
+					keymap.getTarget( key ),
+					k -> loader.get( keymap.getSource( k ) ) );
+		}
+	}
+
+	public static class LoadingCacheAdapter< K, L, V, C extends LoadingCache< L, V > >
+			extends AbstractCacheAdapter< K, L, V, C >
+			implements LoadingCache< K, V >
+	{
+		public LoadingCacheAdapter( final C cache, final KeyBimap< K, L > keymap )
+		{
+			super( cache, keymap );
+		}
+
+		@Override
+		public V get( final K key ) throws ExecutionException
+		{
+			return cache.get( keymap.getTarget( key ) );
+		}
+	}
+
+	public static class ListenableCacheAdapter< K, L, V, C extends ListenableCache< L, V > >
+			extends AbstractCacheAdapter< K, L, V, C >
+			implements ListenableCache< K, V >
+	{
+		public ListenableCacheAdapter( final C cache, final KeyBimap< K, L > keymap )
+		{
+			super( cache, keymap );
+		}
+
+		@Override
+		public V get( final K key, final CacheLoader< ? super K, ? extends V > loader, final RemovalListener< ? super K, ? super V > remover ) throws ExecutionException
+		{
+			return cache.get(
+					keymap.getTarget( key ),
+					k -> loader.get( keymap.getSource( k ) ),
+					( k, v ) -> remover.onRemoval( keymap.getSource( k ), v ) );
+		}
+	}
+
+	public static class ListenableLoadingCacheAdapter< K, L, V, C extends ListenableLoadingCache< L, V > >
+			extends AbstractCacheAdapter< K, L, V, C >
+			implements ListenableLoadingCache< K, V >
+	{
+		public ListenableLoadingCacheAdapter( final C cache, final KeyBimap< K, L > keymap )
+		{
+			super( cache, keymap );
+		}
+
+		@Override
+		public V get( final K key, final RemovalListener< ? super K, ? super V > remover ) throws ExecutionException
+		{
+			return cache.get(
+					keymap.getTarget( key ),
+					( k, v ) -> remover.onRemoval( keymap.getSource( k ), v ) );
+		}
+	}
+}