Converted NGResource to an interface

Author: hugithordarson

ng-appserver/src/main/java/ng/appserver/resources/NGResource.java

@@ -3,33 +3,26 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.UncheckedIOException;
+import java.net.URL;
 import java.util.concurrent.Callable;
 
 /**
  * FIXME: We're currently missing caching of the resource's data // Hugi 2024-06-22
- * FIXME: NGResource should probably be an interface, since we need to accommodate JAR resources, filesystem resources, dynamic resources etc. etc.
+ * FIXME: We need to accommodate JAR resources, filesystem resources, dynamic resources etc. etc. // Hugi 2025-08-03
+ * FIXME: A resource should know it's name, length and possibly content type (although the default implementation may derive that from it's name)
  */
 
-public class NGResource {
+public interface NGResource {
 
 	/**
-	 * A method that will provide us with the actual inputStream
+	 * @return A stream providing the resource data. The stream is the consumer's responsibility to close.
 	 */
-	private Callable<InputStream> _inputStreamSupplier;
-
-	/**
-	 * @return A resource that obtains it's data from the given supplier
-	 */
-	public static NGResource of( final Callable<InputStream> inputStreamSupplier ) {
-		final NGResource resource = new NGResource();
-		resource._inputStreamSupplier = inputStreamSupplier;
-		return resource;
-	}
+	public InputStream inputStream();
 
 	/**
 	 * @return The resource's data as a byte array
 	 */
-	public byte[] bytes() {
+	public default byte[] bytes() {
 
 		try( final InputStream is = inputStream()) {
 			return is.readAllBytes();
@@ -40,19 +33,71 @@ public byte[] bytes() {
 	}
 
 	/**
-	 * @return The resource's data by opening a new inputStream provided by the InputStream supplier
+	 * @return A resource that obtains it's data from the given supplier
+	 */
+	public static NGResource of( final Callable<InputStream> inputStreamSupplier ) {
+		return new NGInputStreamSupplierResource( inputStreamSupplier );
+	}
+
+	/**
+	 * @return A resource that obtains it's data from the given supplier
 	 */
-	public InputStream inputStream() {
-		final Callable<InputStream> provider = _inputStreamSupplier;
+	public static NGResource of( final URL url ) {
+		return new NGClasspathResource( url );
+	}
 
-		try {
-			return provider.call();
+	public static class NGClasspathResource implements NGResource {
+
+		private URL _url;
+
+		/**
+		 * Constructs a new classpath resource from the URL provided
+		 */
+		public NGClasspathResource( URL url ) {
+			_url = url;
 		}
-		catch( IOException e ) {
-			throw new UncheckedIOException( e );
+
+		@Override
+		public InputStream inputStream() {
+			try {
+				return _url.openStream();
+			}
+			catch( IOException e ) {
+				throw new UncheckedIOException( e );
+			}
+		}
+	}
+
+	/**
+	 * A resource obtained from the java class path
+	 */
+	public static class NGInputStreamSupplierResource implements NGResource {
+
+		/**
+		 * A method that will provide us with the actual inputStream
+		 */
+		private Callable<InputStream> _inputStreamSupplier;
+
+		public NGInputStreamSupplierResource( Callable<InputStream> inputStreamSupplier ) {
+			_inputStreamSupplier = inputStreamSupplier;
 		}
-		catch( Exception e ) {
-			throw new RuntimeException( e );
+
+		/**
+		 * @return The resource's data by opening a new inputStream provided by the InputStream supplier
+		 */
+		@Override
+		public InputStream inputStream() {
+			final Callable<InputStream> provider = _inputStreamSupplier;
+
+			try {
+				return provider.call();
+			}
+			catch( IOException e ) {
+				throw new UncheckedIOException( e );
+			}
+			catch( Exception e ) {
+				throw new RuntimeException( e );
+			}
 		}
 	}
 }

ng-appserver/src/main/java/ng/appserver/resources/NGResourceLoader.java

@@ -150,7 +150,7 @@ public Optional<NGResource> resourceWithPath( String resourcePath ) {
 				return Optional.empty();
 			}
 
-			return Optional.of( NGResource.of( resourceURL::openStream ) );
+			return Optional.of( NGResource.of( resourceURL ) );
 		}
 
 		/**