UNIVERSITY OF WEST ATTICA
SCHOOL OF ENGINEERING
DEPARTMENT OF COMPUTER ENGINEERING AND INFORMATICS

University of West Attica · Department of Computer Engineering and Informatics

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Software Development Methodologies

Event Handling

Vasileios Evangelos Athanasiou
Student ID: 19390005

GitHub · LinkedIn

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Supervision

Supervisor: Georgios Prezerakos, Professor

UNIWA Profile · LinkedIn

Co-supervisor: Angelos Georgoulas, Assistant Professor

Scholar · LinkedIn

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Athens, June 2023

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README

Event Handling

This README provides an overview of Exercise 4: Event Handling, part of the Application Development Methodologies laboratory for the 2022-2023 Spring Semester.
The exercises focus on implementing functional logic and event management for GUIs developed in previous sessions.

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Table of Contents

Section	Folder/File	Description
1	INSTALL.md	Installation and execution instructions
2	README.md	Project overview and usage guide
3	assign/	Assignment description documents
3.1	assign/SDM Exercise 4 (Events).pdf	Assignment description (English)
3.2	assign/ΜΑΕ Ασκήση 4 (Events).pdf	Assignment description (Greek)
4	src/	Java GUI projects demonstrating event handling
4.1	src/Ex4_1/	First event-handling exercise project
4.1.1	src/Ex4_1/build/	Compiled build output
4.1.2	src/Ex4_1/build.xml	Apache Ant build configuration
4.1.3	src/Ex4_1/manifest.mf	Application manifest file
4.1.4	src/Ex4_1/nbproject/	NetBeans project configuration files
4.1.5	src/Ex4_1/src/ex4_1/	Java source code package
4.2	src/Ex4_2/	Second event-handling exercise project
4.2.1	src/Ex4_2/build/	Compiled build output
4.2.2	src/Ex4_2/build.xml	Apache Ant build configuration
4.2.3	src/Ex4_2/manifest.mf	Application manifest file
4.2.4	src/Ex4_2/nbproject/	NetBeans project configuration files
4.2.5	src/Ex4_2/src/ex4_2/	Java source code package

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1. Project Overview

Goal: Practice Java event management using standard classes and interfaces.

Key Topics:

• Event management
• Event classes and listener interfaces (ActionListener, WindowListener)
• Adapter classes
• String-to-integer conversion (Integer.parseInt())

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2. Exercises Summary

2.1 Simple Calculator (Exercise 4.1)

Develop functional logic for a basic arithmetic application.

• Add/Subtract: Performs the operation on two input integers and displays the result in a JLabel (e.g., 50+101=151).
• Clear: Resets both text fields.
• Extended Operations: Implement Multiply and Divide buttons.
• Validation: Ensure fields are filled and contain valid integers before processing. Display error messages in the JLabel if inputs are missing or invalid.

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3. Integrated Calculator (Exercise 4.2)

Implement a full calculator interface based on a grid of buttons (0–9, arithmetic operators, and equals).

• Handles standard calculation logic.
• Properly manages window closing events.

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4. Ordering Application (Exercise 4.3)

Develop backend logic for a pizza-style ordering form.

• "Complete Order" Button: Consolidates user selections into a single string.
• Order Summary: Displays Size, Toppings, and Delivery Method in a bottom JLabel.
• Validation: If any required option (Size, Toppings, Delivery) is missing, prompt the user to complete the selection.