From e8ebc8e7d57cdf9a5720785220b274e4fe5c493c Mon Sep 17 00:00:00 2001
From: =?utf8?q?Roland=20H=C3=A4der?= <roland@mxchange.org>
Date: Fri, 6 Nov 2020 16:14:06 +0100
Subject: [PATCH] Rewrites: - Added type-hints: string, int, bool an other
 primitive types - updated core framework
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

Signed-off-by: Roland Häder <roland@mxchange.org>
---
 .../apt-proxy/class_BaseNodeAptProxy.php      |   4 +-
 .../hub/classes/chat/class_BaseNodeChat.php   |   4 +-
 .../socket/class_SocketContainer.php          | 112 ++++++++++--------
 .../classes/crawler/class_BaseNodeCrawler.php |   4 +-
 .../cruncher/class_BaseHubCruncher.php        |   4 +-
 ...odeDistributedHashTableDatabaseWrapper.php |  15 ++-
 .../class_PeerStateLookupDatabaseWrapper.php  |   2 +-
 .../classes/dht/node/class_NodeDhtFacade.php  |  10 +-
 .../socket/class_PackageSocketDiscovery.php   |   7 +-
 .../factories/socket/class_SocketFactory.php  |  15 ++-
 .../package/class_NetworkPackageHandler.php   |  96 ++++++++-------
 .../connection/class_BaseConnectionHelper.php |  76 +++++-------
 .../info/connection/class_ConnectionInfo.php  |  18 ++-
 .../classes/listener/class_BaseListener.php   |  41 +++----
 .../hub/classes/miner/class_BaseHubMiner.php  |   4 +-
 .../hub/classes/nodes/class_BaseHubNode.php   |   8 +-
 .../pools/peer/class_DefaultPeerPool.php      |  35 ++++--
 .../template/class_BaseXmlTemplateEngine.php  |  12 +-
 .../interfaces/apt-proxy/class_AptProxy.php   |   5 +-
 .../hub/interfaces/chat/class_Chatter.php     |   5 +-
 .../container/socket/class_StorableSocket.php |   8 +-
 .../hub/interfaces/crawler/class_Crawler.php  |   5 +-
 .../cruncher/class_CruncherHelper.php         |   5 +-
 .../frontend/class_NodeDhtWrapper.php         |   2 +-
 .../socket/class_DiscoverableSocket.php       |   2 +-
 .../distributable/class_Distributable.php     |   2 +-
 .../interfaces/miner/class_MinerHelper.php    |   2 +-
 .../pool/peer/class_PoolablePeer.php          |   4 +-
 .../hub/interfaces/socket/class_SocketTag.php |   2 +-
 core                                          |   2 +-
 30 files changed, 284 insertions(+), 227 deletions(-)

diff --git a/application/hub/classes/apt-proxy/class_BaseNodeAptProxy.php b/application/hub/classes/apt-proxy/class_BaseNodeAptProxy.php
index 377d5dc4c..b549e0cce 100644
--- a/application/hub/classes/apt-proxy/class_BaseNodeAptProxy.php
+++ b/application/hub/classes/apt-proxy/class_BaseNodeAptProxy.php
@@ -50,8 +50,8 @@ abstract class BaseNodeAptProxy extends BaseHubSystem {
 	 * @param	$version	Version number of this apt-proxy
 	 * @return	void
 	 */
-	public final function enableIsActive ($isActive = TRUE) {
-		$this->isActive = (bool) $isActive;
+	public final function enableIsActive (bool $isActive = TRUE) {
+		$this->isActive = $isActive;
 	}
 
 	/**
diff --git a/application/hub/classes/chat/class_BaseNodeChat.php b/application/hub/classes/chat/class_BaseNodeChat.php
index 09c68ef06..bbe184dc6 100644
--- a/application/hub/classes/chat/class_BaseNodeChat.php
+++ b/application/hub/classes/chat/class_BaseNodeChat.php
@@ -50,8 +50,8 @@ abstract class BaseNodeChat extends BaseHubSystem {
 	 * @param	$version	Version number of this chatter
 	 * @return	void
 	 */
-	public final function enableIsActive ($isActive = TRUE) {
-		$this->isActive = (bool) $isActive;
+	public final function enableIsActive (bool $isActive = TRUE) {
+		$this->isActive = $isActive;
 	}
 
 	/**
diff --git a/application/hub/classes/container/socket/class_SocketContainer.php b/application/hub/classes/container/socket/class_SocketContainer.php
index c45ebf4ef..8c4de84a6 100644
--- a/application/hub/classes/container/socket/class_SocketContainer.php
+++ b/application/hub/classes/container/socket/class_SocketContainer.php
@@ -140,19 +140,27 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 	 * @param	$socketProtocol		Socket protocol (TCP, UDP, file)
 	 * @param	$packageInstance	An instance of a DeliverablePackage class
 	 * @param	$socketType			Socket type (incoming, outgoing, server, file, ...)
-	 * @return	$socketInstance		An instance of this Container class
-	 * @throws	InvalidArgumentException	If socket type is not set in $packageData array
+	 * @return	$socketInstance		An instance of a StorableSocket class
+	 * @throws	InvalidArgumentException	If a parameter is not valid
 	 */
-	public static final function createSocketContainer ($socketResource, $socketProtocol, DeliverablePackage $packageInstance, $socketType) {
-		// Trace message
+	public static final function createSocketContainer ($socketResource, string $socketProtocol, DeliverablePackage $packageInstance, string $socketType) {
+		// Validate parameter
 		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('SOCKET-CONTAINER: socketResource[%s]=%s,socketProtocol=%s,packageInstance[]=%s,socketType=%s - CALLED!', gettype($socketResource), $socketResource, $socketProtocol, gettype($packageInstance), $socketType));
-		//* DEBUG-PRINT: */ printf('[%s:%d]: packageInstance=%s', __METHOD__, __LINE__, print_r($packageInstance, TRUE));
+		if (!is_resource($socketResource)) {
+			// Throw exception
+			throw new InvalidArgumentException(sprintf('socketResource[]=%s is not valid', $socketResource));
+		} elseif (empty($socketProtocol)) {
+			// Throw again
+			throw new InvalidArgumentException('socketProtocol is empty');
+		} elseif (empty($socketType)) {
+			// Throw again
+			throw new InvalidArgumentException('socketType is empty');
+		}
 
 		// Get a new instance
 		$socketInstance = new SocketContainer();
 
 		// Set all values
-		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('SOCKET-CONTAINER: socketResource=%s,socketProtocol=%s', $socketResource, $socketProtocol));
 		$socketInstance->setSocketProtocol($socketProtocol);
 		$socketInstance->setSocketResource($socketResource);
 		$socketInstance->setPackageDataInstance($packageInstance);
@@ -168,10 +176,17 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 	 *
 	 * @param	$unl		A Universal Node Locator
 	 * @return	$matches	Whether $address matches with the one from package data
-	 */
-	public function ifAddressMatches ($unl) {
+	 * @throws	InvalidArgumentException	If a parameter is not valid
+	 */
+	public function ifAddressMatches (string $unl) {
+		// Is parameter valid?
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-SOCKET: unl=%s - CALLED!', strtoupper($this->getSocketProtocol()), $unl));
+		if (empty($unl)) {
+			// Throw again
+			throw new InvalidArgumentException('unl is empty');
+		}
+
 		// Get current package data
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-SOCKET: unl=%s - CALLED!', strtoupper($this->getSocketProtocol()), $unl));
 		$packageInstance = $this->getPackageDataInstance();
 
 		// So, does both match?
@@ -268,13 +283,13 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 	 * @return	$result			Result from asking for peer address
 	 * @throws	InvalidSocketException	If socket is invalid
 	 */
-	public function determineSocketPeerName (&$peerAddress, &$peerPort) {
+	public function determineSocketPeerName (string &$peerAddress, int &$peerPort) {
 		// Should be valid socket
 		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-SOCKET: peerAddress[%s]=%s,peerPort[%s]=%d - CALLED!', strtoupper($this->getSocketProtocol()), gettype($peerAddress), $peerAddress, gettype($peerPort), $peerPort));
 		if (!$this->isValidSocket()) {
 			// Throw exception
 			throw new InvalidSocketException(array($this), self::EXCEPTION_INVALID_SOCKET);
-		} // END - if
+		}
 
 		// Init result
 		$result = FALSE;
@@ -320,7 +335,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		if (!$this->isValidSocket()) {
 			// Throw exception
 			throw new InvalidSocketException(array($this), self::EXCEPTION_INVALID_SOCKET);
-		} // END - if
+		}
 
 		// Get package data
 		$packageInstance = $this->getPackageDataInstance();
@@ -342,7 +357,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		if (!$this->isValidSocket()) {
 			// Throw exception
 			throw new InvalidSocketException(array($this), self::EXCEPTION_INVALID_SOCKET);
-		} // END - if
+		}
 
 		// Get recipient
 		$recipient = $this->getSocketRecipient();
@@ -370,7 +385,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		if (!$this->isValidSocket()) {
 			// Throw exception
 			throw new InvalidSocketException(array($this), self::EXCEPTION_INVALID_SOCKET);
-		} // END - if
+		}
 
 		// Get recipient
 		$recipient = $this->getSocketRecipient();
@@ -417,7 +432,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		if (!$this->isValidSocket()) {
 			// Throw exception
 			throw new InvalidSocketException(array($this), self::EXCEPTION_INVALID_SOCKET);
-		} // END - if
+		}
 
 		// Get it from stored socket resource
 		$socketResource = $this->getSocketResource();
@@ -442,7 +457,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		if (!$this->isValidSocket()) {
 			// Throw exception
 			throw new InvalidSocketException(array($this), self::EXCEPTION_INVALID_SOCKET);
-		} // END - if
+		}
 
 		// Get it from stored socket resource
 		$socketResource = $this->getSocketResource();
@@ -547,7 +562,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		if (!$this->isValidSocket()) {
 			// Throw exception
 			throw new InvalidSocketException(array($this), self::EXCEPTION_INVALID_SOCKET);
-		} // END - if
+		}
 
 		// Try to listen on socket
 		$result = socket_listen($this->getSocketResource());
@@ -569,7 +584,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		if (!$this->isValidSocket()) {
 			// Throw exception
 			throw new InvalidSocketException(array($this), self::EXCEPTION_INVALID_SOCKET);
-		} // END - if
+		}
 
 		// Try to set non-blocking I/O
 		$result = socket_set_nonblock($this->getSocketResource());
@@ -591,7 +606,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		if (!$this->isValidSocket()) {
 			// Throw exception
 			throw new InvalidSocketException(array($this), self::EXCEPTION_INVALID_SOCKET);
-		} // END - if
+		}
 
 		// Tries to set option
 		$result = $this->setSocketOption(SOL_SOCKET, SO_REUSEADDR, 1);
@@ -613,7 +628,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		if (!$this->isValidSocket()) {
 			// Throw exception
 			throw new InvalidSocketException(array($this), self::EXCEPTION_INVALID_SOCKET);
-		} // END - if
+		}
 
 		// Get recipient UNL
 		$unlRecipient = $this->getSocketRecipient();
@@ -646,7 +661,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		if (!$this->isValidSocket()) {
 			// Throw exception
 			throw new BadMethodCallException(sprintf('[%s:%d]: Shutdown on invalid socket. Maybe called already?', __METHOD__, __LINE__), self::EXCEPTION_INVALID_SOCKET);
-		} // END - if
+		}
 
 		// Debug message
 		self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(strtoupper($this->getSocketProtocol()) . '-SOCKET: Shutting down socket ' . $this->getSocketResource());
@@ -662,8 +677,8 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 			if (socket_last_error($this->getSocketResource()) != 107) {
 				// Something bad happened while we shutdown a socket
 				throw new SocketShutdownException($this, self::EXCEPTION_INVALID_SOCKET);
-			} // END - if
-		} // END - if
+			}
+		}
 
 		// Try to make blocking I/O for socket_close()
 		socket_set_block($this->getSocketResource());
@@ -686,18 +701,21 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 	 *
 	 * @param	$connectionType		Type of connection, can be 'incoming', 'outgoing' or 'server'
 	 * @return	$isValid			Whether the provided connection type is valid
+	 * @throws	InvalidArgumentException	If $connectionType is empty
 	 */
-	public function isValidConnectionType ($connectionType) {
-		// Trace message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-SOCKET: connectionType=%d - CALLED!', strtoupper($this->getSocketProtocol()), $connectionType));
+	public function isValidConnectionType (string $connectionType) {
+		// Validate parameter
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-SOCKET: connectionType=%d - CALLED!', strtoupper($this->getSocketProtocol()), $connectionType));
+		if (empty($connectionType)) {
+			// Throw exception
+			throw new InvalidArgumentException('connectionType is empty');
+		}
 
 		// Is it valid?
 		$isValid = in_array($connectionType, $this->connectionTypes, TRUE);
 
-		// Trace message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-SOCKET: isValid=%d - EXIT!', strtoupper($this->getSocketProtocol()), intval($isValid)));
-
 		// Return result
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-SOCKET: isValid=%d - EXIT!', strtoupper($this->getSocketProtocol()), intval($isValid)));
 		return $isValid;
 	}
 
@@ -713,7 +731,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		if (!$this->isValidSocket()) {
 			// Throw exception
 			throw new InvalidSocketException(array($this), self::EXCEPTION_INVALID_SOCKET);
-		} // END - if
+		}
 
 		// Init all arrays, at least readers
 		/* EXTREME-NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-SOCKET: this->socketResource=%s', strtoupper($this->getSocketProtocol()), $this->getSocketResource()));
@@ -773,7 +791,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		if (!$this->isValidSocket()) {
 			// Throw exception
 			throw new InvalidSocketException(array($this), self::EXCEPTION_INVALID_SOCKET);
-		} // END - if
+		}
 
 		/*
 		 * Read raw data from socket. If you change PHP_BINARY_READ to
@@ -797,7 +815,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		// Init peer address (IP)/port
 		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-SOCKET: this->socketResource=%s - CALLED!', strtoupper($this->getSocketProtocol()), $this->getSocketResource()));
 		$peerAddress = '0.0.0.0';
-		$peerPort    = '0';
+		$peerPort    = 0;
 
 		// Call other method
 		$result = $this->determineSocketPeerName($peerAddress, $peerPort);
@@ -808,7 +826,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 			// Set both
 			$this->setPeerAddress($peerAddress);
 			$this->setPeerPort($peerPort);
-		} // END - if
+		}
 
 		// Return result
 		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-SOCKET: result[%s]=%d - EXIT!', strtoupper($this->getSocketProtocol()), gettype($result), intval($result)));
@@ -997,13 +1015,13 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 	 * @throws	InvalidSocketException	If the stored socket resource is no socket resource
 	 * @throws	NoSocketErrorDetectedException	If socket_last_error() gives zero back
 	 */
-	public function handleSocketError ($method, $line) {
+	public function handleSocketError (string $method, int $line) {
 		// This method handles only socket resources
 		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('HUB-SYSTEM: Handling socket errorCode=%d - CALLED!', $this->getLastSocketErrorCode()));
 		if (!$this->isValidSocket()) {
 			// No resource, abort here
 			throw new InvalidSocketException(array($this), self::EXCEPTION_INVALID_SOCKET);
-		} // END - if
+		}
 
 		// Get error code for first validation (0 is not an error)
 		$errorCode = $this->getLastSocketErrorCode();
@@ -1012,7 +1030,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		if ($errorCode == 0) {
 			// No error detected (or previously cleared outside this method)
 			throw new NoSocketErrorDetectedException(array($this), BaseListener::EXCEPTION_NO_SOCKET_ERROR);
-		} // END - if
+		}
 
 		// Get handler (method) name
 		$handlerName = $this->getSocketErrorHandlerFromCode($errorCode);
@@ -1035,7 +1053,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 	 * @return	$handlerName	Call-back method name for the error handler
 	 * @throws	UnsupportedSocketErrorHandlerException If the error handler is not implemented
 	 */
-	protected function getSocketErrorHandlerFromCode ($errorCode) {
+	protected function getSocketErrorHandlerFromCode (int $errorCode) {
 		// Create a name from translated error code
 		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-SOCKET: errorCode=%d - CALLED!', strtoupper($this->getSocketProtocol()), $errorCode));
 		$handlerName = 'handleSocketError' . self::convertToClassName($this->translateSocketErrorCodeToName($errorCode));
@@ -1044,7 +1062,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		if (!method_exists($this, $handlerName)) {
 			// Please implement this
 			throw new UnsupportedSocketErrorHandlerException(array($this, $handlerName, $errorCode), BaseConnectionHelper::EXCEPTION_UNSUPPORTED_ERROR_HANDLER);
-		} // END - if
+		}
 
 		// Return it
 		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-SOCKET: handlerName=%d - EXIT!', strtoupper($this->getSocketProtocol()), $handlerName));
@@ -1254,7 +1272,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 	 * @param	$errorCode	The error code from socket_last_error() to be translated
 	 * @return	$errorName	The translated name (all lower-case, with underlines)
 	 */
-	private function translateSocketErrorCodeToName ($errorCode) {
+	private function translateSocketErrorCodeToName (int $errorCode) {
 		// Unknown error code by default
 		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-SOCKET: errorCode=%d - CALLED!', strtoupper($this->getSocketProtocol()), $errorCode));
 		$errorName = StorableSocket::SOCKET_ERROR_UNKNOWN;
@@ -1315,7 +1333,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 				// Unhandled error code detected, so first debug it because we may want to handle it like the others
 				self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf(strtoupper($this->getSocketProtocol()) . '-SOCKET: Unsupported errorCode=%d,message=%s', $errorCode, socket_strerror($errorCode)));
 				break;
-		} // END - switch
+		}
 
 		// Return translated name
 		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-SOCKET: errorName=%d - EXIT!', strtoupper($this->getSocketProtocol()), $errorName));
@@ -1337,7 +1355,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 		if (!$this->isValidSocket()) {
 			// Throw exception
 			throw new InvalidSocketException(array($this), self::EXCEPTION_INVALID_SOCKET);
-		} // END - if
+		}
 
 		// Set it
 		$result = socket_set_option($this->getSocketResource(), $level, $optionName, $optionValue);
@@ -1353,7 +1371,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 	 * @param	$socketProtocol		Socket protocol
 	 * @return	void
 	 */
-	private function setSocketProtocol ($socketProtocol) {
+	private function setSocketProtocol (string $socketProtocol) {
 		$this->socketProtocol = $socketProtocol;
 	}
 
@@ -1410,7 +1428,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 	 * @param	$socketType		Socket type
 	 * @return	void
 	 */
-	protected function setSocketType ($socketType) {
+	protected function setSocketType (string $socketType) {
 		$this->socketType = $socketType;
 	}
 
@@ -1429,7 +1447,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 	 * @param	$peerAddress	Peer address
 	 * @return	void
 	 */
-	public function setPeerAddress ($peerAddress) {
+	public function setPeerAddress (string $peerAddress) {
 		$this->peerAddress = $peerAddress;
 	}
 
@@ -1448,7 +1466,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 	 * @param	$peerPort	Peer port
 	 * @return	void
 	 */
-	public function setPeerPort ($peerPort) {
+	public function setPeerPort (int $peerPort) {
 		$this->peerPort = $peerPort;
 	}
 
@@ -1467,7 +1485,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 	 * @param	$senderAddress	Sender address
 	 * @return	void
 	 */
-	public function setSenderAddress ($senderAddress) {
+	public function setSenderAddress (string $senderAddress) {
 		$this->senderAddress = $senderAddress;
 	}
 
@@ -1486,7 +1504,7 @@ class SocketContainer extends BaseHubContainer implements StorableSocket, Visita
 	 * @param	$senderPort	Sender port
 	 * @return	void
 	 */
-	public function setSenderPort ($senderPort) {
+	public function setSenderPort (int $senderPort) {
 		$this->senderPort = $senderPort;
 	}
 
diff --git a/application/hub/classes/crawler/class_BaseNodeCrawler.php b/application/hub/classes/crawler/class_BaseNodeCrawler.php
index 4df7bf66d..ac2d34719 100644
--- a/application/hub/classes/crawler/class_BaseNodeCrawler.php
+++ b/application/hub/classes/crawler/class_BaseNodeCrawler.php
@@ -83,8 +83,8 @@ abstract class BaseNodeCrawler extends BaseHubSystem {
 	 * @param	$version	Version number of this crawler
 	 * @return	void
 	 */
-	public final function enableIsActive ($isActive = TRUE) {
-		$this->isActive = (bool) $isActive;
+	public final function enableIsActive (bool $isActive = TRUE) {
+		$this->isActive = $isActive;
 	}
 
 	/**
diff --git a/application/hub/classes/cruncher/class_BaseHubCruncher.php b/application/hub/classes/cruncher/class_BaseHubCruncher.php
index 15771d133..59c348f05 100644
--- a/application/hub/classes/cruncher/class_BaseHubCruncher.php
+++ b/application/hub/classes/cruncher/class_BaseHubCruncher.php
@@ -146,8 +146,8 @@ abstract class BaseHubCruncher extends BaseHubSystem implements Updateable {
 	 * @param	$version	Version number of this cruncher
 	 * @return	void
 	 */
-	public final function enableIsActive ($isActive = TRUE) {
-		$this->isActive = (bool) $isActive;
+	public final function enableIsActive (bool $isActive = TRUE) {
+		$this->isActive = $isActive;
 	}
 
 	/**
diff --git a/application/hub/classes/database/frontend/node/class_NodeDistributedHashTableDatabaseWrapper.php b/application/hub/classes/database/frontend/node/class_NodeDistributedHashTableDatabaseWrapper.php
index e2f7ceb01..aec61b504 100644
--- a/application/hub/classes/database/frontend/node/class_NodeDistributedHashTableDatabaseWrapper.php
+++ b/application/hub/classes/database/frontend/node/class_NodeDistributedHashTableDatabaseWrapper.php
@@ -671,10 +671,15 @@ class NodeDistributedHashTableDatabaseWrapper extends BaseHubDatabaseWrapper imp
 	 * @param	$key			Key to look for
 	 * @param	$value			Value to compare if key matches
 	 * @return	$recipients		An indexed array with DHT recipients
+	 * @throws	InvalidArgumentException	If $key is empty
 	 */
-	public function getResultFromKeyValue ($key, $value) {
-		// Debug message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('DHT-WRAPPER: CALLED!');
+	public function getResultFromKeyValue (string $key, $value) {
+		// Is key parameter valid?
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('DHT-WRAPPER: key=%s,value[%s]=%s - CALLED!', $key, gettype($value), $value));
+		if (empty($key)) {
+			// Throw exception
+			throw new InvalidArgumentException('Parameter key is empty');
+		}
 
 		// Get max recipients
 		$maxRecipients = $this->getConfigInstance()->getConfigEntry('max_dht_recipients');
@@ -688,10 +693,8 @@ class NodeDistributedHashTableDatabaseWrapper extends BaseHubDatabaseWrapper imp
 		// Get a result instance back from DHT database wrapper.
 		$resultInstance = $this->doSelectByCriteria($searchInstance);
 
-		// Debug message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('DHT-WRAPPER: EXIT!');
-
 		// Return result instance
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('DHT-WRAPPER: resultInstance=%s - EXIT!', $resultInstance->__toString()));
 		return $resultInstance;
 	}
 
diff --git a/application/hub/classes/database/frontend/states/class_PeerStateLookupDatabaseWrapper.php b/application/hub/classes/database/frontend/states/class_PeerStateLookupDatabaseWrapper.php
index 90d47ab2e..594de0a5f 100644
--- a/application/hub/classes/database/frontend/states/class_PeerStateLookupDatabaseWrapper.php
+++ b/application/hub/classes/database/frontend/states/class_PeerStateLookupDatabaseWrapper.php
@@ -157,7 +157,7 @@ class PeerStateLookupDatabaseWrapper extends BaseHubDatabaseWrapper implements L
 
 		// Init peer address/port
 		$peerAddress = '0.0.0.0';
-		$peerPort    = '0';
+		$peerPort    = 0;
 
 		// Get peer name
 		if (!$socketInstance->determineSocketPeerName($peerAddress, $peerPort)) {
diff --git a/application/hub/classes/dht/node/class_NodeDhtFacade.php b/application/hub/classes/dht/node/class_NodeDhtFacade.php
index c2e992f3b..0eb971241 100644
--- a/application/hub/classes/dht/node/class_NodeDhtFacade.php
+++ b/application/hub/classes/dht/node/class_NodeDhtFacade.php
@@ -428,8 +428,16 @@ class NodeDhtFacade extends BaseDht implements DistributableNode, Registerable {
 	 * @param	$key		Key to search for
 	 * @param	$value		Value to check on found key
 	 * @return	$recipiens	Array with DHT recipients from given key/value pair
+	 * @throws	InvalidArgumentException	If $key is empty
 	 */
-	public function findRecipientsByKey ($key, $value) {
+	public function findRecipientsByKey (string $key, $value) {
+		// Is key parameter valid?
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('NODE-DHT-FACADE: key=%s,value[%s]=%s - CALLED!', $key, gettype($value), $value));
+		if (empty($key)) {
+			// Throw exception
+			throw new InvalidArgumentException('Parameter key is empty');
+		}
+
 		// Look for all suitable nodes
 		$resultInstance = $this->getWrapperInstance()->getResultFromKeyValue($key, $value);
 
diff --git a/application/hub/classes/discovery/recipient/socket/class_PackageSocketDiscovery.php b/application/hub/classes/discovery/recipient/socket/class_PackageSocketDiscovery.php
index fc0a24148..a631ca43d 100644
--- a/application/hub/classes/discovery/recipient/socket/class_PackageSocketDiscovery.php
+++ b/application/hub/classes/discovery/recipient/socket/class_PackageSocketDiscovery.php
@@ -148,11 +148,14 @@ class PackageSocketDiscovery extends BaseRecipientDiscovery implements Discovera
 	 * @throws	InvalidArgumentException	If one of the parameters are not valid
 	 * @throws	LogicException	If the discovered listener instance has no pool set
 	 */
-	public function discoverSocket (DeliverablePackage $packageInstance, $connectionType) {
+	public function discoverSocket (DeliverablePackage $packageInstance, string $connectionType) {
 		// Make sure all parameters are valid
 		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('PACKAGE-SOCKET-DISOVERY: packageInstance=%s,connectionType=%s - CALLED!', $packageInstance->__toString(), $connectionType));
 		//* PRINTR-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('PACKAGE-SOCKET-DISOVERY: packageInstance=' . print_r($packageInstance, TRUE));
-		if (($connectionType != StorableSocket::CONNECTION_TYPE_INCOMING) && ($connectionType != StorableSocket::CONNECTION_TYPE_OUTGOING)) {
+		if (empty($connectionType)) {
+			// Throw exception
+			throw new InvalidArgumentException('Parameter connectionType is empty');
+		} elseif (($connectionType != StorableSocket::CONNECTION_TYPE_INCOMING) && ($connectionType != StorableSocket::CONNECTION_TYPE_OUTGOING)) {
 			// Abort here
 			throw new InvalidArgumentException(sprintf('connectionType=%s is whether "%s" nor "%s".',
 				$connectionType,
diff --git a/application/hub/classes/factories/socket/class_SocketFactory.php b/application/hub/classes/factories/socket/class_SocketFactory.php
index b00926d4d..3219a1877 100644
--- a/application/hub/classes/factories/socket/class_SocketFactory.php
+++ b/application/hub/classes/factories/socket/class_SocketFactory.php
@@ -17,6 +17,7 @@ use Org\Mxchange\CoreFramework\Registry\GenericRegistry;
 use Org\Mxchange\CoreFramework\Socket\InvalidSocketException;
 
 // Import SPL stuff
+use \InvalidArgumentException;
 use \LogicException;
 use \SplFileInfo;
 
@@ -475,10 +476,20 @@ class SocketFactory extends ObjectFactory {
 	 * @param	$socketResource		Valid socket resource from calling socket_accept()
 	 * @param	$socketProtocol		Protcol of socket (e.g. 'tcp', 'udp', see StorableSocket interface for valid values
 	 * @return	$socketInstance		An instance of a StorableSocket class
+	 * @throws	InvalidArgumentException	If a parameter is not valid
 	 */
-	public static final function createIncomingSocketInstance ($socketResource, $socketProtocol) {
-		// Create package instance
+	public static final function createIncomingSocketInstance ($socketResource, string $socketProtocol) {
+		// Validate parameter
 		/* NOISY-DEBUG */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('SOCKET-FACTORY: socketResource[%s]=%s,socketProtocol=%s - CALLED!', gettype($socketResource), $socketResource, $socketProtocol));
+		if (!is_resource($socketResource)) {
+			// Throw exception
+			throw new InvalidArgumentException(sprintf('socketResource[]=%s is not valid', gettype($socketResource)));
+		} elseif (empty($socketProtocol)) {
+			// Throw it again
+			throw new InvalidArgumentException('socketProtocol is empty');
+		}
+
+		// Create package instance
 		$packageInstance = ObjectFactory::createObjectByConfiguredName('package_data_class');
 
 		// Create socket instance
diff --git a/application/hub/classes/handler/package/class_NetworkPackageHandler.php b/application/hub/classes/handler/package/class_NetworkPackageHandler.php
index 53a5a8427..ab25ee015 100644
--- a/application/hub/classes/handler/package/class_NetworkPackageHandler.php
+++ b/application/hub/classes/handler/package/class_NetworkPackageHandler.php
@@ -46,6 +46,7 @@ use Org\Mxchange\CoreFramework\Visitor\Visitor;
 use \BadMethodCallException;
 use \InvalidArgumentException;
 use \Iterator;
+use \UnexpectedValueException;
 
 /**
  * A NetworkPackageHandler class. This class implements Deliverable and Receivable
@@ -514,10 +515,17 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 	 *
 	 * @param	$packageInstance	An instance of a DeliverablePackage class in an array
 	 * @return	$hash				Hash for given package content
+	 * @throws	InvalidArgumentException	If $packageInstance has no sessionId set
 	 */
 	public function getHashFromPackageSessionId (DeliverablePackage $packageInstance) {
-		// Create the hash
+		// Is session id set?
 		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('NETWORK-PACKAGE-HANDLER: packageInstance=%s - CALLED!', $packageInstance->__toString()));
+		if (empty($packageInstance->getSessionId())) {
+			// Throw exception
+			throw new InvalidArgumentException('packageInstance has no sessionId set.');
+		}
+
+		// Create the hash
 		// @TODO md5() is very weak, but it needs to be fast
 		$hash = md5(sprintf(self::CONTENT_CHECKSUM_MASK,
 			$packageInstance->getContentMessage(),
@@ -547,7 +555,7 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 		 * target because it causes an overload on the network and may be
 		 * abused for attacking the network with large packages.
 		 */
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('NETWORK-PACKAGE-HANDLER: packageInstance=%s - CALLED!', $packageInstance->__toString()));
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('NETWORK-PACKAGE-HANDLER: packageInstance=%s - CALLED!', $packageInstance->__toString()));
 		$discoveryInstance = PackageDiscoveryFactory::createPackageDiscoveryInstance();
 
 		// Discover all recipients, this may throw an exception
@@ -586,6 +594,9 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 		 */
 		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: Calling discoveryInstance->clearRecipients() ...');
 		$discoveryInstance->clearRecipients();
+
+		// Trace message
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: EXIT!');
 	}
 
 	/**
@@ -610,33 +621,28 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 		 * which (configurable!) protocol should be used for that type of
 		 * package.
 		 */
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('NETWORK-PACKAGE-HANDLER: packageInstance=%s - CALLED!', $packageInstance->__toString()));
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('NETWORK-PACKAGE-HANDLER: packageInstance=%s - CALLED!', $packageInstance->__toString()));
 		$discoveryInstance = SocketDiscoveryFactory::createSocketDiscoveryInstance();
 
 		// Now discover the right socket instance from given package data
 		$socketInstance = $discoveryInstance->discoverSocket($packageInstance, StorableSocket::CONNECTION_TYPE_OUTGOING);
 
 		// Get the connection helper from registry
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: Reached line ' . __LINE__ . ' after discoverSocket() has been called.');
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: Reached line ' . __LINE__ . ' after discoverSocket() has been called.');
 		$helperInstance = GenericRegistry::getRegistry()->getInstance('connection');
 
-		// Debug message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: stateInstance=' . $helperInstance->getStateInstance());
-
-		// And make sure it is valid
-		assert($helperInstance instanceof ConnectionHelper);
-
 		// Get connection info class
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('NETWORK-PACKAGE-HANDLER: stateInstance=%s', $helperInstance->getStateInstance()));
 		$infoInstance = ConnectionInfoFactory::createConnectionInfoInstance($helperInstance->getProtocolName(), 'helper');
 
 		// Will the info instance with connection helper data
 		$infoInstance->fillWithConnectionHelperInformation($helperInstance);
 
 		// Is it not there?
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: Reached line ' . __LINE__ . ' before isSocketRegistered() has been called.');
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: Reached line ' . __LINE__ . ' before isSocketRegistered() has been called.');
 		if (($socketInstance->isValidSocket()) && (!$this->getRegistryInstance()->isSocketRegistered($infoInstance, $socketInstance))) {
 			// Then register it
-			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: Registering socket ' . $socketInstance . ' ...');
+			/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('NETWORK-PACKAGE-HANDLER: Registering socket %s ...', $socketInstance));
 			$this->getRegistryInstance()->registerSocketInstance($infoInstance, $socketInstance);
 		} elseif (!$helperInstance->getStateInstance()->isPeerStateConnected()) {
 			// Is not connected, then we cannot send
@@ -647,15 +653,15 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 		}
 
 		// Make sure the connection is up
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: Reached line ' . __LINE__ . ' after isSocketRegistered() has been called.');
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: Reached line ' . __LINE__ . ' after isSocketRegistered() has been called.');
 		$helperInstance->getStateInstance()->validatePeerStateConnected();
 
 		// Enqueue it again on the out-going queue, the connection is up and working at this point
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: Reached line ' . __LINE__ . ' after validatePeerStateConnected() has been called.');
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: Reached line ' . __LINE__ . ' after validatePeerStateConnected() has been called.');
 		$this->getStackInstance()->pushNamed(self::STACKER_NAME_OUTGOING, $packageInstance);
 
 		// Trace message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: Reached line ' . __LINE__ . ' after pushNamed() has been called.');
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: Reached line ' . __LINE__ . ' after pushNamed() has been called.');
 	}
 
 	/**
@@ -665,10 +671,8 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 	 * @return	void
 	 */
 	private function sendOutgoingRawPackageData (DeliverablePackage $packageInstance) {
-		// Trace message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('NETWORK-PACKAGE-HANDLER: packageInstance=%s - CALLED!', $packageInstance->__toString()));
-
 		// Init sent bytes
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('NETWORK-PACKAGE-HANDLER: packageInstance=%s - CALLED!', $packageInstance->__toString()));
 		$sentBytes = 0;
 
 		// Get the right connection instance
@@ -680,12 +684,8 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 		// Get helper instance
 		$helperInstance = $infoInstance->getHelperInstance();
 
-		// Some sanity-checks on the object
-		//* DEBUG-DIE: */ die(': p1=' . $infoInstance->getProtocolName() . ',p2=' . $helperInstance->getProtocolName() . ',infoInstance=' . print_r($infoInstance, TRUE));
-		assert($helperInstance instanceof ConnectionHelper);
-		assert($infoInstance->getProtocolName() == $helperInstance->getProtocolName());
-
 		// Is this connection still alive?
+		//* DEBUG-DIE: */ die(': p1=' . $infoInstance->getProtocolName() . ',p2=' . $helperInstance->getProtocolName() . ',infoInstance=' . print_r($infoInstance, TRUE));
 		if ($helperInstance->isShuttedDown()) {
 			// This connection is shutting down
 			// @TODO We may want to do somthing more here?
@@ -696,7 +696,7 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 		$helperInstance->sendRawPackageData($packageInstance);
 
 		// Debug message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: EXIT!');
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: EXIT!');
 	}
 
 	/**
@@ -707,10 +707,8 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 	 * @return	$hash		Hash as hex-encoded string
 	 */
 	private function generatePackageHash ($content, $senderId) {
-		// Debug message
-		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: content()=' . strlen($content) . ',senderId=' . $senderId . ' - CALLED!');
-
 		// Assert on variables
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: content()=' . strlen($content) . ',senderId=' . $senderId . ' - CALLED!');
 		assert(!empty($content));
 		assert(!empty($senderId));
 
@@ -783,14 +781,19 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 	 *
 	 * @param	$helperInstance		An instance of a HubHelper class
 	 * @return	void
+	 * @throws	UnexpectedValueException	If the helper instance contains now raw template data
 	 */
 	public function enqueueRawDataFromTemplate (HubHelper $helperInstance) {
-		// Debug message
-		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: helperInstance=' . $helperInstance->__toString() . ' - CALLED!');
-
 		// Get the raw content ...
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: helperInstance=' . $helperInstance->__toString() . ' - CALLED!');
 		$content = $helperInstance->getTemplateInstance()->getRawTemplateData();
-		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('content(' . strlen($content) . ')=' . $content);
+
+		// Should not be empty
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('NETWORK-PACKAGE-HANDLER: content(%d)=%s', strlen($content), $content));
+		if (empty($content)) {
+			// Abort here
+			throw new UnexpectedValueException('content cannot be empty.');
+		}
 
 		// ... and compress it
 		$compressed = $this->getCompressorInstance()->compressStream($content);
@@ -813,12 +816,8 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 			$this->getHashFromContent($compressed)
 		);
 
-		// Make sure required data is there
-		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: Enqueueing package for recipientType=' . $helperInstance->getRecipientType() . ' ...');
-		assert(!empty($content));
-		assert($this->getNodeInstance()->getSessionId() != '');
-
 		// Init package instance
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: Enqueueing package for recipientType=' . $helperInstance->getRecipientType() . ' ...');
 		$packageInstance = ObjectFactory::createObjectByConfiguredName('package_data_class');
 
 		// Set all data
@@ -884,7 +883,13 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 	public function isPackageWaitingForDelivery () {
 		// Check whether the stacker is not empty
 		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: CALLED!');
-		$isWaitingDelivery = (($this->getStackInstance()->isStackInitialized(self::STACKER_NAME_OUTGOING)) && (!$this->getStackInstance()->isStackEmpty(self::STACKER_NAME_OUTGOING)));
+		$isWaitingDelivery = (
+			(
+				$this->getStackInstance()->isStackInitialized(self::STACKER_NAME_OUTGOING)
+			) && (
+				!$this->getStackInstance()->isStackEmpty(self::STACKER_NAME_OUTGOING)
+			)
+		);
 
 		// Return the result
 		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('NETWORK-PACKAGE-HANDLER: isWaitingDelivery=%d - EXIT!', intval($isWaitingDelivery)));
@@ -899,7 +904,13 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 	public function isEncodedDataPending () {
 		// Check whether the stacker is not empty
 		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: CALLED!');
-		$isPending = (($this->getStackInstance()->isStackInitialized(self::STACKER_NAME_OUTGOING_STREAM)) && (!$this->getStackInstance()->isStackEmpty(self::STACKER_NAME_OUTGOING_STREAM)));
+		$isPending = (
+			(
+				$this->getStackInstance()->isStackInitialized(self::STACKER_NAME_OUTGOING_STREAM)
+			) && (
+				!$this->getStackInstance()->isStackEmpty(self::STACKER_NAME_OUTGOING_STREAM)
+			)
+		);
 
 		// Return the result
 		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('NETWORK-PACKAGE-HANDLER: isPending=%d - EXIT!', intval($isPending)));
@@ -917,10 +928,8 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 	 * @throws	NoTargetException	If no target can't be determined
 	 */
 	public function declareEnqueuedPackage () {
-		// Debug message
-		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: CALLED!');
-
 		// Make sure this method isn't working if there is no package enqueued
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: CALLED!');
 		if (!$this->isPackageEnqueued()) {
 			// This is not fatal but should be avoided
 			self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: No raw package data waiting declaration, but ' . __METHOD__ . ' has been called!');
@@ -1028,7 +1037,7 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 		}
 
 		// Debug message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: EXIT!');
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: EXIT!');
 	}
 
 	/**
@@ -1497,7 +1506,8 @@ class NetworkPackageHandler extends BaseHubHandler implements Deliverable, Recei
 		$packageInstance = $this->getStackInstance()->popNamed(self::STACKER_NAME_NEW_MESSAGE);
 
 		// Generate the hash of comparing it
-		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NETWORK-PACKAGE-HANDLER: packageInstance=%s,senderId=%s,senderPrivateKeyHash=%s', $packageInstance->__toString(), $packageInstance->getSenderId(), $packageInstance->getSenderPrivateKeyHash()));
+		/* DEBUG-DIE: */ die(sprintf('[%s:%d]: packageInstance=%s', __METHOD__, __LINE__, print_r($packageInstance, TRUE)));
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('NETWORK-PACKAGE-HANDLER: packageInstance=%s,senderId=%s,senderPrivateKeyHash=%s', $packageInstance->__toString(), $packageInstance->getSenderId(), $packageInstance->getSenderPrivateKeyHash()));
 		if (empty($packageInstance->getSenderId())) {
 			// Invalid $packageInstance
 			throw new InvalidArgumentException('packageInstance does not contain senderId');
diff --git a/application/hub/classes/helper/connection/class_BaseConnectionHelper.php b/application/hub/classes/helper/connection/class_BaseConnectionHelper.php
index 9c2c87c72..4a9d49df8 100644
--- a/application/hub/classes/helper/connection/class_BaseConnectionHelper.php
+++ b/application/hub/classes/helper/connection/class_BaseConnectionHelper.php
@@ -126,13 +126,20 @@ abstract class BaseConnectionHelper extends BaseHubSystemHelper implements Visit
 	 */
 	private function getConnectionClassNameFromSocket () {
 		// Get recipient address/port
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: CALLED!');
 		$recipientAddress = $this->getSocketInstance()->getSocketRecipientAddress();
 		$recipientPort = $this->getSocketInstance()->getSocketRecipientPort();
 
 		// Construct it
-		$class = sprintf('%s:%d:%s', $recipientAddress, $recipientPort, parent::__toString());
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: recipientAddress=%s,recipientPort=%d', $recipientAddress, $recipientPort));
+		$class = sprintf('%s:%d:%s',
+			$recipientAddress,
+			$recipientPort,
+			parent::__toString()
+		);
 
 		// ... and return it
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: class=%s - EXIT!', $class));
 		return $class;
 	}
 
@@ -143,7 +150,11 @@ abstract class BaseConnectionHelper extends BaseHubSystemHelper implements Visit
 	 */
 	private function initState() {
 		// Get the state factory and create the initial state.
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: CALLED!');
 		PeerStateFactory::createPeerStateInstanceByName('init', $this);
+
+		// Trace message
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: EXIT!');
 	}
 
 	/**
@@ -160,19 +171,15 @@ abstract class BaseConnectionHelper extends BaseHubSystemHelper implements Visit
 	 * @return	$chunkData		Raw data chunk
 	 */
 	private function getRawDataFromPackageArray (DeliverablePackage $packageInstance) {
-		// Debug message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: currentFinalHash=' . $this->currentFinalHash);
-
 		// Make sure the final hash is set
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: currentFinalHash=' . $this->currentFinalHash);
 		assert((is_string($this->currentFinalHash)) && (!empty($this->currentFinalHash)));
 
 		// Get the next raw data chunk from the fragmenter
 		$rawDataChunk = $this->getFragmenterInstance()->getNextRawDataChunk($this->currentFinalHash);
 
-		// Debug message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: rawDataChunk=' . print_r($rawDataChunk, TRUE));
-
 		// Get chunk hashes and chunk data
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: rawDataChunk=' . print_r($rawDataChunk, TRUE));
 		$chunkHashes = array_keys($rawDataChunk);
 		$chunkData   = array_values($rawDataChunk);
 
@@ -180,21 +187,19 @@ abstract class BaseConnectionHelper extends BaseHubSystemHelper implements Visit
 		$rawData = '';
 
 		// Is the required data there?
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: chunkHashes[]=' . count($chunkHashes) . ',chunkData[]=' . count($chunkData));
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('chunkData='.print_r($chunkData, TRUE));
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: chunkHashes()=' . count($chunkHashes) . ',chunkData()=' . count($chunkData));
+		//* PRINTR-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('chunkData='.print_r($chunkData, TRUE));
 		if ((isset($chunkHashes[0])) && (isset($chunkData[0]))) {
 			// Remember this chunk as queued
 			$this->queuedChunks[$chunkHashes[0]] = $chunkData[0];
 
 			// Return the raw data
-			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: rawData()=' . strlen($chunkData[0]) . ' bytes.');
+			/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: rawData()=' . strlen($chunkData[0]) . ' bytes.');
 			$rawData = $chunkData[0];
 		} // END - if
 
-		// Trace message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: rawData()=%d - EXIT!', strlen($rawData)));
-
 		// Return raw data
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: rawData(%d)=%s - EXIT!', strlen($rawData), $rawData));
 		return $rawData;
 	}
 
@@ -204,7 +209,7 @@ abstract class BaseConnectionHelper extends BaseHubSystemHelper implements Visit
 	 * @param	$isInitialized		Name of used protocol in this connection
 	 * @return	void
 	 */
-	protected final function setIsInitialized ($isInitialized) {
+	protected final function setIsInitialized (bool $isInitialized) {
 		$this->isInitialized = $isInitialized;
 	}
 
@@ -242,7 +247,7 @@ abstract class BaseConnectionHelper extends BaseHubSystemHelper implements Visit
 	 */
 	public function sendRawPackageData (DeliverablePackage $packageInstance) {
 		// Trace message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: packageInstance=%s - CALLED!', $packageInstance->__toString()));
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: packageInstance=%s - CALLED!', $packageInstance->__toString()));
 
 		// The helper's state must be 'connected'
 		$this->getStateInstance()->validatePeerStateConnected();
@@ -250,15 +255,11 @@ abstract class BaseConnectionHelper extends BaseHubSystemHelper implements Visit
 		// Implode the package data array and fragement the resulting string, returns the final hash
 		$finalHash = $this->getFragmenterInstance()->fragmentPackageArray($packageInstance, $this);
 
-		// Trace message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: finalHash[%s]=%s', gettype($finalHash), $finalHash));
-
 		// Is the final hash set?
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: finalHash[%s]=%s', gettype($finalHash), $finalHash));
 		if ($finalHash !== TRUE) {
-			// Debug message
-			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: Setting finalHash=' . $finalHash . ',currentFinalHash[' . gettype($this->currentFinalHash) . ']=' . $this->currentFinalHash);
-
 			// Set final hash
+			/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: Setting finalHash=%s,currentFinalHash[%s]=%s', $finalHash, gettype($this->currentFinalHash), $this->currentFinalHash));
 			$this->currentFinalHash = $finalHash;
 		} // END - if
 
@@ -271,50 +272,33 @@ abstract class BaseConnectionHelper extends BaseHubSystemHelper implements Visit
 
 		// Fill sending buffer with data
 		while (TRUE) {
-			// Debug message
-			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: dataStream()=%d - BEFORE!', strlen($dataStream)));
-
 			// Convert the package data array to a raw data stream
+			/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: dataStream()=%d - BEFORE!', strlen($dataStream)));
 			$dataStream = $this->getRawDataFromPackageArray($packageInstance);
 
-			// Debug message
-			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: dataStream()=%d - AFTER!', strlen($dataStream)));
-
 			// Is it empty?
+			/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: dataStream()=%d - AFTER!', strlen($dataStream)));
 			if (strlen($dataStream) == 0) {
-				// Debug message
-				//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: dataStream is now empty, exiting loop ...');
-
 				// Abort here
+				/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: dataStream is now empty, exiting loop ...');
 				break;
 			} // END - if
 
-			// Debug message
-			//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: Adding ' . strlen($dataStream) . ' bytes to the sending buffer ...');
-
 			// Add raw data
+			/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: Adding %d bytes to the sending buffer ...', strlen($dataStream)));
 			$rawData .= $dataStream;
 		} // END - while
 
-		// Debug message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: rawData()=%d - after loop ...', strlen($rawData)));
-
-		// Nothing to sent is bad news, so assert on it
-		assert(strlen($rawData) > 0);
-
 		// Calculate buffer size
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: rawData()=%d - after loop ...', strlen($rawData)));
 		$bufferSize = $this->getConfigInstance()->getConfigEntry($this->getProtocolName() . '_buffer_length');
 
-		// Debug message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: bufferSize=%d', $bufferSize));
-
 		// Encode the raw data with our output-stream
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: bufferSize=%d', $bufferSize));
 		$encodedData = $this->getOutputStreamInstance()->streamData($rawData);
 
-		// Debug message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: socketResource[%s]=%s', gettype($this->getSocketInstance()->getSocketResource()), $this->getSocketInstance()->getSocketResource()));
-
 		// Init array
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-HELPER: socketResource[%s]=%s', gettype($this->getSocketInstance()->getSocketResource()), $this->getSocketInstance()->getSocketResource()));
 		$encodedDataArray = array(
 			NetworkPackageHandler::RAW_INDEX_FINAL_HASH      => $this->currentFinalHash,
 			NetworkPackageHandler::RAW_INDEX_ENCODED_DATA    => $encodedData,
@@ -328,7 +312,7 @@ abstract class BaseConnectionHelper extends BaseHubSystemHelper implements Visit
 		$this->getPackageHandlerInstance()->getStackInstance()->pushNamed(NetworkPackageHandler::STACKER_NAME_OUTGOING_STREAM, $encodedDataArray);
 
 		// Trace message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: EXIT!');
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('CONNECTION-HELPER: EXIT!');
 	}
 
 	/**
diff --git a/application/hub/classes/info/connection/class_ConnectionInfo.php b/application/hub/classes/info/connection/class_ConnectionInfo.php
index 87ab06435..47c62820c 100644
--- a/application/hub/classes/info/connection/class_ConnectionInfo.php
+++ b/application/hub/classes/info/connection/class_ConnectionInfo.php
@@ -14,6 +14,9 @@ use Org\Shipsimu\Hub\Locator\Node\LocateableNode;
 use Org\Mxchange\CoreFramework\Registry\Registerable;
 use Org\Mxchange\CoreFramework\Socket\InvalidSocketException;
 
+// Import SPL stuff
+use \InvalidArgumentException;
+
 /**
  * A Connection information class
  *
@@ -57,10 +60,17 @@ class ConnectionInfo extends BaseInfo implements ShareableInfo, Registerable {
 	 *
 	 * @param	$connectionType		Connection type (valid: 'incoming', 'outgoing', 'server')
 	 * @return	$infoInstance	An instance of a ShareableInfo class
+	 * @throws	InvalidArgumentException	If $connectionType is empty
 	 */
-	public final static function createConnectionInfo ($connectionType) {
-		// Get new instance
+	public final static function createConnectionInfo (string $connectionType) {
+		// Validate parameter
 		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-INFO: connectionType=%s - CALLED!', $connectionType));
+		if (empty($connectionType)) {
+			// Throw exception
+			throw new InvalidArgumentException('connectionType is empty');
+		}
+
+		// Get new instance
 		$infoInstance = new ConnectionInfo();
 
 		// Set connection type here
@@ -77,7 +87,7 @@ class ConnectionInfo extends BaseInfo implements ShareableInfo, Registerable {
 	 * @param	$connectionType		Connection type
 	 * @return	void
 	 */
-	private function setConnectionType ($connectionType) {
+	private function setConnectionType (string $connectionType) {
 		$this->connectionType = $connectionType;
 	}
 
@@ -141,7 +151,7 @@ class ConnectionInfo extends BaseInfo implements ShareableInfo, Registerable {
 		// Init variables
 		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('CONNECTION-INFO: socketInstance=%s - CALLED!', $socketInstance->__toString()));
 		$socketAddress = '0.0.0.0';
-		$socketPort    = '0';
+		$socketPort    = 0;
 
 		// Get peer name
 		if (!$socketInstance->determineSocketPeerName($socketAddress, $socketPort)) {
diff --git a/application/hub/classes/listener/class_BaseListener.php b/application/hub/classes/listener/class_BaseListener.php
index cf91676fd..be43cdbcb 100644
--- a/application/hub/classes/listener/class_BaseListener.php
+++ b/application/hub/classes/listener/class_BaseListener.php
@@ -25,6 +25,7 @@ use Org\Mxchange\CoreFramework\Visitor\Visitable;
 use Org\Mxchange\CoreFramework\Visitor\Visitor;
 
 // Import SPL stuff
+use \InvalidArgumentException;
 use \LogicException;
 
 /**
@@ -113,8 +114,8 @@ abstract class BaseListener extends BaseHubSystem implements Visitable {
 	 * @param	$listenAddress	The address this listener should listen on
 	 * @return	void
 	 */
-	protected final function setListenAddress ($listenAddress) {
-		$this->listenAddress = (string) $listenAddress;
+	protected final function setListenAddress (string $listenAddress) {
+		$this->listenAddress = $listenAddress;
 	}
 
 	/**
@@ -132,8 +133,8 @@ abstract class BaseListener extends BaseHubSystem implements Visitable {
 	 * @param	$listenPort		The port this listener should listen on
 	 * @return	void
 	 */
-	protected final function setListenPort ($listenPort) {
-		$this->listenPort = (int) $listenPort;
+	protected final function setListenPort (int $listenPort) {
+		$this->listenPort = $listenPort;
 	}
 
 	/**
@@ -151,7 +152,7 @@ abstract class BaseListener extends BaseHubSystem implements Visitable {
 	 * @param	$configEntry	The configuration entry holding our listen address
 	 * @return	void
 	 */
-	public final function setListenAddressByConfiguration ($configEntry) {
+	public final function setListenAddressByConfiguration (string $configEntry) {
 		$this->setListenAddress($this->getConfigInstance()->getConfigEntry($configEntry));
 	}
 
@@ -161,7 +162,7 @@ abstract class BaseListener extends BaseHubSystem implements Visitable {
 	 * @param	$configEntry	The configuration entry holding our listen port
 	 * @return	void
 	 */
-	public final function setListenPortByConfiguration ($configEntry) {
+	public final function setListenPortByConfiguration (string $configEntry) {
 		$this->setListenPort($this->getConfigInstance()->getConfigEntry($configEntry));
 	}
 
@@ -348,13 +349,19 @@ abstract class BaseListener extends BaseHubSystem implements Visitable {
 	 *
 	 * @param	$peerSuffix		Suffix for peer name (e.g. :0 for TCP(/UDP?) connections)
 	 * @return	void
+	 * @throws	InvalidArgumentException	If $peerSuffix is empty
 	 * @throws	LogicException	If no info instance can be created
 	 */
-	protected function doListenSocketSelect ($peerSuffix) {
-		// Check on all instances
+	protected function doListenSocketSelect (string $peerSuffix) {
+		// Validate parameter and socket instance
 		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-LISTENER: peerSuffix=%s - CALLED!', strtoupper($this->getProtocolName()), $peerSuffix));
-		assert($this->getPoolInstance() instanceof Poolable);
-		assert($this->getSocketInstance()->isValidSocket());
+		if (empty($peerSuffix)) {
+			// Throw exception
+			throw new InvalidArgumentException('peerSuffix is empty');
+		} elseif(!$this->getSocketInstance()->isValidSocket()) {
+			// Invalid socket
+			throw new LogicException(sprintf('this->socketInstance->socketResource=%s is not valid', $this->getSocketInstance()->getSocketResource()));
+		}
 
 		// Get next socket instance from pool over the factory
 		$socketInstance = SocketFactory::createNextAcceptedSocketFromPool($this->getPoolInstance(), $this->getSocketInstance());
@@ -382,7 +389,7 @@ abstract class BaseListener extends BaseHubSystem implements Visitable {
 
 		// Init peer address/port
 		$peerAddress = '0.0.0.0';
-		$peerPort    = '0';
+		$peerPort    = 0;
 
 		// Get peer name
 		if (!$socketInstance->determineSocketPeerName($peerAddress, $peerPort)) {
@@ -412,10 +419,8 @@ abstract class BaseListener extends BaseHubSystem implements Visitable {
 	 * @return	$accepts		Whether this listener does accept
 	 */
 	public function ifListenerAcceptsPackageData (DeliverablePackage $packageInstance) {
-		// Trace message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-LISTENER: packageInstance=%s - CALLED!', strtoupper($this->getProtocolName()), $packageInstance));
-
 		// Check if same socket protocol
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-LISTENER: packageInstance=%s - CALLED!', strtoupper($this->getProtocolName()), $packageInstance));
 		$socketProtocol = $this->getSocketInstance()->getSocketProtocol();
 
 		// Get UNL instance
@@ -424,16 +429,12 @@ abstract class BaseListener extends BaseHubSystem implements Visitable {
 		// Get protocol from it
 		$unlProtocol = $locatorInstance->getUnlProtocol();
 
-		// Debug message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-LISTENER: locatorInstance->unlProtocol=%s,socketProtocol=%s', strtoupper($this->getProtocolName()), $unlProtocol, $socketProtocol));
-
 		// Is same protocol?
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-LISTENER: locatorInstance->unlProtocol=%s,socketProtocol=%s', strtoupper($this->getProtocolName()), $unlProtocol, $socketProtocol));
 		$accepts = ($unlProtocol == $socketProtocol);
 
-		// Trace message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-LISTENER: accepts=%d - EXIT!', strtoupper($this->getProtocolName()), $accepts));
-
 		// Return the result
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('%s-LISTENER: accepts=%d - EXIT!', strtoupper($this->getProtocolName()), $accepts));
 		return $accepts;
 	}
 
diff --git a/application/hub/classes/miner/class_BaseHubMiner.php b/application/hub/classes/miner/class_BaseHubMiner.php
index 32a8d2809..c44f4387b 100644
--- a/application/hub/classes/miner/class_BaseHubMiner.php
+++ b/application/hub/classes/miner/class_BaseHubMiner.php
@@ -158,8 +158,8 @@ abstract class BaseHubMiner extends BaseHubSystem implements Updateable {
 	 * @param	$version	Version number of this miner
 	 * @return	void
 	 */
-	public final function enableIsActive ($isActive = TRUE) {
-		$this->isActive = (bool) $isActive;
+	public final function enableIsActive (bool $isActive = TRUE) {
+		$this->isActive = $isActive;
 	}
 
 	/**
diff --git a/application/hub/classes/nodes/class_BaseHubNode.php b/application/hub/classes/nodes/class_BaseHubNode.php
index 88a432b1f..4d1501a4a 100644
--- a/application/hub/classes/nodes/class_BaseHubNode.php
+++ b/application/hub/classes/nodes/class_BaseHubNode.php
@@ -654,8 +654,8 @@ abstract class BaseHubNode extends BaseHubSystem implements Updateable, AddableC
 	 * @param	$isActive	Whether the hub is active
 	 * @return	void
 	 */
-	public final function enableIsActive ($isActive = TRUE) {
-		$this->isActive = (bool) $isActive;
+	public final function enableIsActive (bool $isActive = TRUE) {
+		$this->isActive = $isActive;
 	}
 
 	/**
@@ -730,7 +730,7 @@ abstract class BaseHubNode extends BaseHubSystem implements Updateable, AddableC
 	 * @param	$acceptAnnouncements	Whether this node accepts announcements (default: TRUE)
 	 * @return	void
 	 */
-	protected final function enableAcceptingAnnouncements ($acceptAnnouncements = TRUE) {
+	protected final function enableAcceptingAnnouncements (bool $acceptAnnouncements = TRUE) {
 		$this->acceptAnnouncements = $acceptAnnouncements;
 	}
 
@@ -740,7 +740,7 @@ abstract class BaseHubNode extends BaseHubSystem implements Updateable, AddableC
 	 * @param	$acceptDhtBootstrap	Whether this node accepts DHT bootstrap requests (default: TRUE)
 	 * @return	void
 	 */
-	public final function enableAcceptDhtBootstrap ($acceptDhtBootstrap = TRUE) {
+	public final function enableAcceptDhtBootstrap (bool $acceptDhtBootstrap = TRUE) {
 		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('NODE: Enabling DHT bootstrap requests ...');
 		$this->acceptDhtBootstrap = $acceptDhtBootstrap;
 	}
diff --git a/application/hub/classes/pools/peer/class_DefaultPeerPool.php b/application/hub/classes/pools/peer/class_DefaultPeerPool.php
index 9bdd7cfde..7f57e148f 100644
--- a/application/hub/classes/pools/peer/class_DefaultPeerPool.php
+++ b/application/hub/classes/pools/peer/class_DefaultPeerPool.php
@@ -17,6 +17,7 @@ use Org\Shipsimu\Hub\Pool\Peer\PoolablePeer;
 use Org\Mxchange\CoreFramework\Socket\InvalidSocketException;
 
 // Import SPL stuff
+use \InvalidArgumentException;
 use \LogicException;
 
 /**
@@ -102,11 +103,16 @@ class DefaultPeerPool extends BasePool implements PoolablePeer {
 	 * @param	$socketInstance		An instance of a StorableSocket class
 	 * @param	$connectionType		Type of connection, can only be 'incoming', 'outgoing' or 'server'
 	 * @return	void
+	 * @throws	InvalidArgumentException	If $connectionType is empty
 	 * @throws	InvalidConnectionTypeException	If the provided connection type is not valid
 	 */
-	public function addPeer (StorableSocket $socketInstance, $connectionType) {
-		// Debug message
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('DEFAULT-PEER-POOL: socketResource[' . gettype($socketInstance->getSocketResource()) . ']=' . $socketInstance->getSocketResource() . ',connectionType=' . $connectionType . ' - CALLED!');
+	public function addPeer (StorableSocket $socketInstance, string $connectionType) {
+		// Validate parameter
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('DEFAULT-PEER-POOL: socketResource[%s]=%s,connectionType=%s - CALLED!', gettype($socketInstance->getSocketResource()), $socketInstance->getSocketResource(), $connectionType));
+		if (empty($connectionType)) {
+			// Throw exception
+			throw new InvalidArgumentException('connectionType is empty');
+		}
 
 		// Validate the socket
 		$this->validateSocket($socketInstance);
@@ -115,14 +121,11 @@ class DefaultPeerPool extends BasePool implements PoolablePeer {
 		if (!$socketInstance->isValidConnectionType($connectionType)) {
 			// Is not a valid connection type!
 			throw new InvalidConnectionTypeException(array($this, $connectionType), self::EXCEPTION_INVALID_CONNECTION_TYPE);
-		} // END - if
+		}
 
 		// Default is this peer's IP
 		$peerAddress = '0.0.0.0';
-		$peerPort    = '0';
-
-		// Trace message
-		//* NOSY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('DEFAULT-PEER-POOL: Calling this->getListenerInstance() ...');
+		$peerPort    = 0;
 
 		// The socket resource should not match server socket
 		if (!$this->getListenerInstance()->getSocketInstance()->equals($socketInstance)) {
@@ -190,8 +193,16 @@ class DefaultPeerPool extends BasePool implements PoolablePeer {
 	 * @param	$connectionType		Type of connection, can only be 'incoming', 'outgoing' or 'server'
 	 * @return	$sockets			An array with sockets of given type
 	 * @throws	InvalidConnectionTypeException	If the found connection type is not valid
+	 * @throws	InvalidArgumentException	If $connectionType is empty
 	 */
-	public function getSocketsByConnectionType ($connectionType) {
+	public function getSocketsByConnectionType (string $connectionType) {
+		// Validate parameter
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('DEFAULT-PEER-POOL: connectionType=%s - CALLED!', $connectionType));
+		if (empty($connectionType)) {
+			// Throw exception
+			throw new InvalidArgumentException('connectionType is empty');
+		}
+
 		// Get the array list
 		$socketArrays = $this->getArrayFromList('pool');
 
@@ -226,9 +237,9 @@ class DefaultPeerPool extends BasePool implements PoolablePeer {
 	 * @throws	InvalidConnectionTypeException	If the provided connection type is not valid
 	 * @throws	LogicException		If an expected array element is missing
 	 */
-	public function getSocketFromPackageInstance (DeliverablePackage $packageInstance, $connectionType = NULL) {
+	public function getSocketFromPackageInstance (DeliverablePackage $packageInstance, string $connectionType = NULL) {
 		// Default is no socket
-		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('DEFAULT-PEER-POOL:packageInstance=%s,connectionType[%s]=%s - CALLED!', $packageInstance->__toString(), gettype($connectionType), $connectionType));
+		//* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('DEFAULT-PEER-POOL: packageInstance=%s,connectionType[%s]=%s - CALLED!', $packageInstance->__toString(), gettype($connectionType), $connectionType));
 		$socketInstance = NULL;
 
 		// Resolve recipient (UNL) into a handler instance
@@ -263,7 +274,7 @@ class DefaultPeerPool extends BasePool implements PoolablePeer {
 
 			// Init peer address/port
 			$peerAddress = '0.0.0.0';
-			$peerPort    = '0';
+			$peerPort    = 0;
 
 			// Try to get the "peer"'s name
 			/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('DEFAULT-PEER-POOL: socketInstance->socketResource=%s,socketInstance->socketProtocol=%s,socketArray[%s]=%s', $socketArray[Poolable::SOCKET_ARRAY_INSTANCE]->getSocketResource(), $socketArray[Poolable::SOCKET_ARRAY_INSTANCE]->getSocketProtocol(), Poolable::SOCKET_ARRAY_CONN_TYPE, $socketArray[Poolable::SOCKET_ARRAY_CONN_TYPE]));
diff --git a/application/hub/classes/template/class_BaseXmlTemplateEngine.php b/application/hub/classes/template/class_BaseXmlTemplateEngine.php
index fba4658f6..b86515537 100644
--- a/application/hub/classes/template/class_BaseXmlTemplateEngine.php
+++ b/application/hub/classes/template/class_BaseXmlTemplateEngine.php
@@ -9,6 +9,9 @@ use Org\Mxchange\CoreFramework\Factory\Template\XmlTemplateEngineFactory;
 use Org\Mxchange\CoreFramework\Registry\GenericRegistry;
 use Org\Mxchange\CoreFramework\Template\Engine\BaseTemplateEngine;
 
+// Import SPL stuff
+use \InvalidArgumentException;
+
 /**
  * A generic XML template engine class
  *
@@ -230,7 +233,14 @@ abstract class BaseXmlTemplateEngine extends BaseTemplateEngine {
 	 * @param	$key	Key to read from
 	 * @return	$value	Value from variable
 	 */
-	public function readXmlData ($key) {
+	public function readXmlData (string $key) {
+		// Is key parameter valid?
+		/* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-XML-TEMPLATE-ENGINE: key=%s - CALLED!', $key));
+		if (empty($key)) {
+			// Throw exception
+			throw new InvalidArgumentException('Parameter key is empty');
+		}
+
 		// Read the variable
 		$value = parent::readVariable($key, 'general');
 
diff --git a/application/hub/interfaces/apt-proxy/class_AptProxy.php b/application/hub/interfaces/apt-proxy/class_AptProxy.php
index 38ff9351b..cced7559d 100644
--- a/application/hub/interfaces/apt-proxy/class_AptProxy.php
+++ b/application/hub/interfaces/apt-proxy/class_AptProxy.php
@@ -65,7 +65,7 @@ interface AptProxy extends HubInterface {
 	 * @param	$version	Version number of this apt-proxy
 	 * @return	void
 	 */
-	function enableIsActive ($isActive = TRUE);
+	function enableIsActive (bool $isActive = TRUE);
 
 	/**
 	 * Determines whether the apt-proxy is active
@@ -74,6 +74,3 @@ interface AptProxy extends HubInterface {
 	 */
 	function isActive ();
 }
-
-// [EOF]
-?>
diff --git a/application/hub/interfaces/chat/class_Chatter.php b/application/hub/interfaces/chat/class_Chatter.php
index a8b44e355..5fd84af77 100644
--- a/application/hub/interfaces/chat/class_Chatter.php
+++ b/application/hub/interfaces/chat/class_Chatter.php
@@ -65,7 +65,7 @@ interface Chatter extends HubInterface {
 	 * @param	$version	Version number of this chatter
 	 * @return	void
 	 */
-	function enableIsActive ($isActive = TRUE);
+	function enableIsActive (bool $isActive = TRUE);
 
 	/**
 	 * Determines whether the chatter is active
@@ -74,6 +74,3 @@ interface Chatter extends HubInterface {
 	 */
 	function isActive ();
 }
-
-// [EOF]
-?>
diff --git a/application/hub/interfaces/container/socket/class_StorableSocket.php b/application/hub/interfaces/container/socket/class_StorableSocket.php
index b6bec8e9a..f87dd245a 100644
--- a/application/hub/interfaces/container/socket/class_StorableSocket.php
+++ b/application/hub/interfaces/container/socket/class_StorableSocket.php
@@ -124,7 +124,7 @@ interface StorableSocket extends FrameworkInterface {
 	 * @return	$result			Result from asking for peer address
 	 * @throws	InvalidSocketException	If stored socket is invalid
 	 */
-	function determineSocketPeerName (&$peerAddress, &$peerPort);
+	function determineSocketPeerName (string &$peerAddress, int &$peerPort);
 
 	/**
 	 * Calls socket_select() on stored socket resource
@@ -216,7 +216,7 @@ interface StorableSocket extends FrameworkInterface {
 	 * @param	$unl		A Universal Node Locator
 	 * @return	$matches	Whether $address matches with the one from package data
 	 */
-	function ifAddressMatches ($unl);
+	function ifAddressMatches (string $unl);
 
 	/**
 	 * Checks whether the given socket matches with stored
@@ -284,7 +284,7 @@ interface StorableSocket extends FrameworkInterface {
 	 * @throws	InvalidSocketException	If the stored socket resource is no socket resource
 	 * @throws	NoSocketErrorDetectedException	If socket_last_error() gives zero back
 	 */
-	function handleSocketError ($method, $line);
+	function handleSocketError (string $method, int $line);
 
 	/**
 	 * Do the shutdown sequence for this connection helper
@@ -301,7 +301,7 @@ interface StorableSocket extends FrameworkInterface {
 	 * @param	$connectionType		Type of connection, can be 'incoming', 'outgoing' or 'server'
 	 * @return	$isValid			Whether the provided connection type is valid
 	 */
-	function isValidConnectionType ($connectionType);
+	function isValidConnectionType (string $connectionType);
 
 	/**
 	 * Clears last socket error
diff --git a/application/hub/interfaces/crawler/class_Crawler.php b/application/hub/interfaces/crawler/class_Crawler.php
index c43d9bdaa..3a57461aa 100644
--- a/application/hub/interfaces/crawler/class_Crawler.php
+++ b/application/hub/interfaces/crawler/class_Crawler.php
@@ -66,7 +66,7 @@ interface Crawler extends HubInterface {
 	 * @param	$version	Version number of this crawler
 	 * @return	void
 	 */
-	function enableIsActive ($isActive = TRUE);
+	function enableIsActive (bool $isActive = TRUE);
 
 	/**
 	 * Determines whether the crawler is active
@@ -83,6 +83,3 @@ interface Crawler extends HubInterface {
 	 */
 	function initCrawler (Stateable $stateInstance);
 }
-
-// [EOF]
-?>
diff --git a/application/hub/interfaces/cruncher/class_CruncherHelper.php b/application/hub/interfaces/cruncher/class_CruncherHelper.php
index acc8fd00f..5f6fb41f2 100644
--- a/application/hub/interfaces/cruncher/class_CruncherHelper.php
+++ b/application/hub/interfaces/cruncher/class_CruncherHelper.php
@@ -74,7 +74,7 @@ interface CruncherHelper extends HubInterface {
 	 * @param	$version	Version number of this cruncher
 	 * @return	void
 	 */
-	function enableIsActive ($isActive = TRUE);
+	function enableIsActive (bool $isActive = TRUE);
 
 	/**
 	 * Determines whether the cruncher is active
@@ -90,6 +90,3 @@ interface CruncherHelper extends HubInterface {
 	 */
 	function initBufferQueues ();
 }
-
-// [EOF]
-?>
diff --git a/application/hub/interfaces/database/frontend/class_NodeDhtWrapper.php b/application/hub/interfaces/database/frontend/class_NodeDhtWrapper.php
index e73f9720f..4447fd20f 100644
--- a/application/hub/interfaces/database/frontend/class_NodeDhtWrapper.php
+++ b/application/hub/interfaces/database/frontend/class_NodeDhtWrapper.php
@@ -172,7 +172,7 @@ interface NodeDhtWrapper extends DatabaseWrapper {
 	 * @param	$value			Value to compare if key matches
 	 * @return	$recipients		An indexed array with DHT recipients
 	 */
-	function getResultFromKeyValue ($key, $value);
+	function getResultFromKeyValue (string $key, $value);
 
 	/**
 	 * Enable DHT bootstrap request acceptance for local node
diff --git a/application/hub/interfaces/discovery/recipient/socket/class_DiscoverableSocket.php b/application/hub/interfaces/discovery/recipient/socket/class_DiscoverableSocket.php
index d1acb3b18..64637efbf 100644
--- a/application/hub/interfaces/discovery/recipient/socket/class_DiscoverableSocket.php
+++ b/application/hub/interfaces/discovery/recipient/socket/class_DiscoverableSocket.php
@@ -40,7 +40,7 @@ interface DiscoverableSocket extends DiscoverableRecipient {
 	 * @throws	NoListGroupException	If the procol group is not found in peer list
 	 * @throws	NullPointerException	If listenerInstance is NULL
 	 */
-	function discoverSocket (DeliverablePackage $packageInstance, $connectionType);
+	function discoverSocket (DeliverablePackage $packageInstance, string $connectionType);
 
 	/**
 	 * Tries to dicover the right listener instance
diff --git a/application/hub/interfaces/distributable/class_Distributable.php b/application/hub/interfaces/distributable/class_Distributable.php
index 1388ed7dc..cb497e733 100644
--- a/application/hub/interfaces/distributable/class_Distributable.php
+++ b/application/hub/interfaces/distributable/class_Distributable.php
@@ -112,7 +112,7 @@ interface Distributable extends HubInterface {
 	 * @param	$value			Value to check on found key
 	 * @return	$recipientList	Array with DHT recipients from given key/value pair
 	 */
-	function findRecipientsByKey ($key, $value);
+	function findRecipientsByKey (string $key, $value);
 
 	/**
 	 * Enable DHT bootstrap request acceptance for local node
diff --git a/application/hub/interfaces/miner/class_MinerHelper.php b/application/hub/interfaces/miner/class_MinerHelper.php
index 64f08745d..656ee3f44 100644
--- a/application/hub/interfaces/miner/class_MinerHelper.php
+++ b/application/hub/interfaces/miner/class_MinerHelper.php
@@ -75,7 +75,7 @@ interface MinerHelper extends HubInterface {
 	 * @param	$version	Version number of this miner
 	 * @return	void
 	 */
-	function enableIsActive ($isActive = TRUE);
+	function enableIsActive (bool $isActive = TRUE);
 
 	/**
 	 * Determines whether the miner is active
diff --git a/application/hub/interfaces/pool/peer/class_PoolablePeer.php b/application/hub/interfaces/pool/peer/class_PoolablePeer.php
index f28774d05..17b50a40c 100644
--- a/application/hub/interfaces/pool/peer/class_PoolablePeer.php
+++ b/application/hub/interfaces/pool/peer/class_PoolablePeer.php
@@ -38,7 +38,7 @@ interface PoolablePeer extends Poolable, SocketTag {
 	 * @return	void
 	 * @throws	InvalidConnectionTypeException	If the provided connection type is not valid
 	 */
-	function addPeer (StorableSocket $socketInstance, $connectionType);
+	function addPeer (StorableSocket $socketInstance, string $connectionType);
 
 	/**
 	 * Getter for array of all socket resources
@@ -61,6 +61,6 @@ interface PoolablePeer extends Poolable, SocketTag {
 	 * @return	$sockets			An array with sockets of given type
 	 * @throws	InvalidConnectionTypeException	If the found connection type is not valid
 	 */
-	function getSocketsByConnectionType ($connectionType);
+	function getSocketsByConnectionType (string $connectionType);
 
 }
diff --git a/application/hub/interfaces/socket/class_SocketTag.php b/application/hub/interfaces/socket/class_SocketTag.php
index 1f955dc46..936540dbc 100644
--- a/application/hub/interfaces/socket/class_SocketTag.php
+++ b/application/hub/interfaces/socket/class_SocketTag.php
@@ -37,6 +37,6 @@ interface SocketTag extends HubInterface {
 	 * @return	$socketInstance		An instance of a StorableSocket class
 	 * @throws	InvalidConnectionTypeException	If the provided connection type is not valid
 	 */
-	function getSocketFromPackageInstance (DeliverablePackage $packageInstance, $connectionType = NULL);
+	function getSocketFromPackageInstance (DeliverablePackage $packageInstance, string $connectionType = NULL);
 
 }
diff --git a/core b/core
index 6d6b58a10..c15d02389 160000
--- a/core
+++ b/core
@@ -1 +1 @@
-Subproject commit 6d6b58a1042e6ad5d6277f8ff5144c95f1abd427
+Subproject commit c15d02389e67a880e7b4c6b19f2b06722efa4e6f
-- 
2.39.5