Merge pull request #8 from informatik-ag-ngl/f/object_handling

Added method to handle incoming objects

src/main/java/envoy/server/LoginCredentialProcessor.java

@@ -0,0 +1,29 @@
+package envoy.server;
+
+import envoy.data.LoginCredentials;
+import envoy.data.User;
+
+/**
+ * This {@link ObjectProcessor} handles {@link LoginCredentials}.<br>
+ * <br>
+ * Project: <strong>envoy-server-standalone</strong><br>
+ * File: <strong>LoginCredentialProcessor.java</strong><br>
+ * Created: <strong>30.12.2019</strong><br>
+ *
+ * @author Kai S. K. Engelbart
+ * @since Envoy Server Standalone v0.1-alpha
+ */
+public class LoginCredentialProcessor implements ObjectProcessor<LoginCredentials, User> {
+
+	// TODO: Acquire user IDs from database
+	private static long currentUserId = 1;
+
+	@Override
+	public Class<LoginCredentials> getInputClass() { return LoginCredentials.class; }
+
+	@Override
+	public User process(LoginCredentials input) {
+		System.out.println("Received login credentials " + input);
+		return new User(currentUserId++, input.getName());
+	}
+}

src/main/java/envoy/server/MessageProcessor.java

@@ -0,0 +1,22 @@
+package envoy.server;
+
+import envoy.data.Message;
+
+/**
+ * This {@link ObjectProcessor} handles incoming {@link Message}s.<br>
+ * <br>
+ * Project: <strong>envoy-server-standalone</strong><br>
+ * File: <strong>MessageProcessor.java</strong><br>
+ * Created: <strong>30.12.2019</strong><br>
+ *
+ * @author Kai S. K. Engelbart
+ * @since Envoy Server Standalone v0.1-alpha
+ */
+public class MessageProcessor implements ObjectProcessor<Message, Void> {
+
+	@Override
+	public Class<Message> getInputClass() { return Message.class; }
+
+	@Override
+	public Void process(Message input) { return null; }
+}

src/main/java/envoy/server/ObjectMessageProcessor.java

@@ -1,29 +1,65 @@
 package envoy.server;
 
 import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.util.Set;
 
 import com.jenkov.nioserver.IMessageProcessor;
 import com.jenkov.nioserver.Message;
 import com.jenkov.nioserver.WriteProxy;
 
 /**
+ * Handles incoming objects.<br>
+ * <br>
  * Project: <strong>envoy-server-standalone</strong><br>
  * File: <strong>ObjectMessageProcessor.java</strong><br>
  * Created: <strong>28.12.2019</strong><br>
- * 
+ *
  * @author Kai S. K. Engelbart
  * @since Envoy Server Standalone v0.1-alpha
  */
 public class ObjectMessageProcessor implements IMessageProcessor {
 
+	private final Set<ObjectProcessor<?, ?>> processors;
+
+	/**
+	 * The constructor to set the {@link ObjectProcessor}s.
+	 *
+	 * @param processors the {@link ObjectProcessor} to set
+	 * @since Envoy Server Standalone v0.1-alpha
+	 */
+	public ObjectMessageProcessor(Set<ObjectProcessor<?, ?>> processors) { this.processors = processors; }
+
+	@SuppressWarnings("unchecked")
 	@Override
 	public void process(Message message, WriteProxy writeProxy) {
 		try (ObjectInputStream in = new ObjectInputStream(new ByteArrayInputStream(message.sharedArray, message.offset + 4, message.length - 4))) {
 			Object obj = in.readObject();
-			// TODO: Process pipeline
 			System.out.println("Read object: " + obj.toString());
+
+			// Process object
+			processors.stream().filter(p -> p.getInputClass().isInstance(obj)).forEach((@SuppressWarnings("rawtypes") ObjectProcessor p) -> {
+				Object responseObj = p.process(p.getInputClass().cast(obj));
+				if (responseObj != null) {
+					// Create message targeted at the client
+					Message response = writeProxy.getMessage();
+					response.socketId = message.socketId;
+
+					// Serialize object to byte array
+					ByteArrayOutputStream baos = new ByteArrayOutputStream();
+					try (ObjectOutputStream oout = new ObjectOutputStream(baos)) {
+						oout.writeObject(responseObj);
+					} catch (IOException e) {
+						e.printStackTrace();
+					}
+					byte[] objBytes = baos.toByteArray();
+					response.writeToMessage(objBytes);
+					writeProxy.enqueue(response);
+				}
+			});
 		} catch (IOException | ClassNotFoundException e) {
 			e.printStackTrace();
 		}

src/main/java/envoy/server/ObjectMessageReader.java

@@ -11,10 +11,12 @@ import com.jenkov.nioserver.MessageBuffer;
 import com.jenkov.nioserver.Socket;
 
 /**
+ * This {@link IMessageReader} decodes serialized Java objects.<br>
+ * <br>
  * Project: <strong>envoy-server-standalone</strong><br>
  * File: <strong>ObjectMessageReader.java</strong><br>
  * Created: <strong>28.12.2019</strong><br>
- * 
+ *
  * @author Kai S. K. Engelbart
  * @since Envoy Server Standalone v0.1-alpha
  */
@@ -24,6 +26,14 @@ public class ObjectMessageReader implements IMessageReader {
 	private Message			nextMessage;
 	private MessageBuffer	messageBuffer;
 
+	private int fromByteArray(byte[] bytes, int offset) {
+		return ((bytes[offset] & 0xFF) << 24) | ((bytes[offset + 1] & 0xFF) << 16) | ((bytes[offset + 2] & 0xFF) << 8)
+				| ((bytes[offset + 3] & 0xFF) << 0);
+	}
+
+	@Override
+	public List<Message> getMessages() { return completeMessages; }
+
 	@Override
 	public void init(MessageBuffer messageBuffer) {
 		this.messageBuffer	= messageBuffer;
@@ -55,12 +65,4 @@ public class ObjectMessageReader implements IMessageReader {
 
 		buffer.clear();
 	}
-
-	private int fromByteArray(byte[] bytes, int offset) {
-		return ((bytes[offset] & 0xFF) << 24) | ((bytes[offset + 1] & 0xFF) << 16) | ((bytes[offset + 2] & 0xFF) << 8)
-				| ((bytes[offset + 3] & 0xFF) << 0);
-	}
-
-	@Override
-	public List<Message> getMessages() { return completeMessages; }
 }

src/main/java/envoy/server/ObjectProcessor.java

@@ -0,0 +1,30 @@
+package envoy.server;
+
+/**
+ * This interface defines methods for processing objects of a specific
+ * type incoming from a client.<br>
+ * <br>
+ * Project: <strong>envoy-server-standalone</strong><br>
+ * File: <strong>ObjectProcessor.java</strong><br>
+ * Created: <strong>30.12.2019</strong><br>
+ *
+ * @author Kai S. K. Engelbart
+ * @param <T> type of the request object
+ * @param <U> type of the response object
+ * @since Envoy Server Standalone v0.1-alpha
+ */
+public interface ObjectProcessor<T, U> {
+
+	/**
+	 * @return the Class of the request object
+	 * @since Envoy Server Standalone v0.1-alpha
+	 */
+	Class<T> getInputClass();
+
+	/**
+	 * @param input the request object
+	 * @return the response object
+	 * @since Envoy Server Standalone v0.1-alpha
+	 */
+	U process(T input);
+}

src/main/java/envoy/server/Startup.java

@@ -1,21 +1,35 @@
 package envoy.server;
 
 import java.io.IOException;
+import java.util.HashSet;
+import java.util.Set;
 
 import com.jenkov.nioserver.Server;
 
 /**
+ * Starts the server.<br>
+ * <br>
  * Project: <strong>envoy-server-standalone</strong><br>
  * File: <strong>Startup.java</strong><br>
  * Created: <strong>24.12.2019</strong><br>
- * 
+ *
  * @author Kai S. K. Engelbart
  * @since Envoy Server Standalone v0.1-alpha
  */
 public class Startup {
 
+	/**
+	 * Starts the server.
+	 *
+	 * @param args the run configuration. Currently unused.
+	 * @throws IOException if the server crashes
+	 * @since Envoy Server Standalone v0.1-alpha
+	 */
 	public static void main(String[] args) throws IOException {
-		Server server = new Server(8080, () -> new ObjectMessageReader(), new ObjectMessageProcessor());
+		Set<ObjectProcessor<?, ?>> processors = new HashSet<>();
+		processors.add(new LoginCredentialProcessor());
+		processors.add(new MessageProcessor());
+		Server server = new Server(8080, () -> new ObjectMessageReader(), new ObjectMessageProcessor(processors));
 		server.start();
 	}
 }