COS3711 Assignment 3 (COMPLETE ANSWERS) Semester 2025

,COS3711 Assignment 3 (COMPLETE ANSWERS)
Semester 2 2025 - DUE 2025; 100% TRUSTED
Complete, trusted solutions and explanations.

I’ll give you both: (A) a clear class/UML design for the assignment and
(B) a runnable C++/Qt project skeleton (CMake) with the key classes
and glue code you’ll need. I’ll include concrete headers/implementation
skeletons you can paste into files and extend.

I won’t overload with every single UI widget line-by-line (that would be
huge), but I provide the full architecture, model classes,
thread/serialization worker, TCP client & server, and a solid
QMainWindow skeleton wired into the models — enough to compile,
run and continue building UI logic.



1) High-level design / UML (textual)

Use these design patterns:

 Factory: to create Box/Cylinder and produce the correct code
(B/C).
 Memento: backup/restore of the unallocated container list (storing
cloned container state in memory).
 Model/View: QAbstractListModel or
QStringListModel for unallocated list;
QAbstractTableModel or QStandardItemModel for
server display.
 Worker Thread: SerializationWorker (QRunnable or
QObject moved to QThread) to build XML and send to TCP
server.
 Observer / Signals: model updates notify UI.

, UML (textual):
QObject
└─ Container (abstract, QObject)
+QString code
+double weight
+int volume()
+virtual void toXml(QXmlStreamWriter&) = 0
+virtual Container* clone() const = 0

Container <- Box (QObject)
+double length, breadth, height

Container <- Cylinder (QObject)
+double diameter, height

ContainerFactory
+static Container* createBox(...)
+static Container* createCylinder(...)

Pallet (QObject)
+int number
+QList<Container*> containers
+double totalWeight()
+int totalVolume()

PalletManager (QObject)
+QMap<int, Pallet*> pallets

UnallocatedListModel : QAbstractListModel
holds QList<Container*>

Memento
+QVector<QByteArray> serializedContainers

SerializationWorker : QObject
+signals: xmlReady(QString), finished(bool)
+slots: start()

TcpClientSender : uses QTcpSocket to send XML to 127.0.0.1:6164

ServerApp (separate project)
- QTcpServer, accepts incoming XML, parse with QXmlStreamReader,
fill QStandardItemModel (display in QTreeView)