better network structure

app/src/main/java/network/server/KeepAliveHandler.java

@@ -0,0 +1,49 @@
+package network.server;
+
+import java.util.Random;
+
+import network.protocol.packets.KeepAlivePacket;
+
+public class KeepAliveHandler {
+
+	private final ServerConnexion serverConnexion;
+
+	private static final int KEEP_ALIVE_COOLDOWN = 5 * 1000;
+
+	private long lastKeepAlive = 0;
+	private long lastSend = 0;
+	private volatile boolean keepAliveRecieved = false;
+
+	public KeepAliveHandler(ServerConnexion serverConnexion) {
+		this.serverConnexion = serverConnexion;
+		sendKeepAlive();
+	}
+
+	public boolean update() {
+		var currentTime = System.currentTimeMillis();
+		if (currentTime - lastSend > KEEP_ALIVE_COOLDOWN) {
+			if (keepAliveRecieved) {
+				sendKeepAlive();
+			} else {
+				System.out.println("Zombie");
+				serverConnexion.close();
+				return false;
+			}
+		}
+		return true;
+	}
+
+	public void recievedKeepAlive(long keepAliveId) {
+		if (lastKeepAlive == keepAliveId)
+			this.keepAliveRecieved = true;
+	}
+
+	private void sendKeepAlive() {
+		Random r = new Random();
+		lastKeepAlive = r.nextLong();
+		lastSend = System.currentTimeMillis();
+		keepAliveRecieved = false;
+		this.serverConnexion.sendPacket(new KeepAlivePacket(lastKeepAlive));
+	}
+
+}