feat: add factory enum

[huunghia98er]

Pull Request Template

What does this PR do?

1. Refactors the existing Factory Pattern implementation to use Factory Enum Pattern.

• Moves object creation logic into enum (FileProcessorType)

• Removes the need for a separate factory class

2. Applies singleton via InstanceHolder for each processor

Why is this change necessary?

• Simplifies the codebase by eliminating boilerplate factory classes

• Improves readability and maintainability

• Leverages type-safe enum-based instantiation

• Aligns with modern Java practices (e.g. Enum Singleton)

[github-actions]

PR Summary

This PR refactors the Factory Pattern implementation to use the Factory Enum Pattern. It moves object creation logic into an enum (FileProcessorType), removes the need for a separate factory class, and applies a singleton pattern via InstanceHolder for each processor. This simplifies the codebase, improves readability and maintainability, and leverages type-safe enum-based instantiation.

Changes

File	Summary
factory-enum/README.md	This file provides a comprehensive guide to the Factory Enum Pattern in Java. It includes a real-world analogy, a programmatic example using FileProcessor, and a discussion of when to use this pattern, its benefits, and trade-offs.
factory-enum/etc/factory-sequence-diagram.png	New file: Sequence diagram for the Factory Enum pattern.
factory-enum/etc/factory.urm.png	New file: UML diagram for the Factory Enum pattern.
factory-enum/etc/factory.urm.puml	New file: PlantUML script for generating the UML diagram of the Factory Enum pattern.
factory-enum/pom.xml	This file configures the Maven project, including dependencies for logging (SLF4j, Logback) and testing (JUnit Jupiter).
factory-enum/src/main/java/com/iluwatar/factory/App.java	This Java class demonstrates the usage of the FileProcessorType enum to create and use instances of FileProcessor implementations.
factory-enum/src/main/java/com/iluwatar/factory/ExcelProcessor.java	This class implements the FileProcessor interface for processing Excel files and uses the singleton pattern.
factory-enum/src/main/java/com/iluwatar/factory/FileProcessor.java	This interface defines the contract for file processors, specifying a method to get a description.
factory-enum/src/main/java/com/iluwatar/factory/FileProcessorType.java	This enum manages the creation and access of different file processor instances using the Factory Enum pattern.
factory-enum/src/main/java/com/iluwatar/factory/PDFProcessor.java	This class implements the FileProcessor interface for processing PDF files and uses the singleton pattern.
factory-enum/src/test/java/com/iluwatar/factory/AppTest.java	This test class verifies that the main application runs without exceptions.
factory-enum/src/test/java/com/iluwatar/factory/FileProcessorTest.java	This test class contains unit tests for the FileProcessorType enum and its associated classes.
pom.xml	The factory-enum module was added to the list of modules in the parent pom.xml file.

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autogenerated by presubmit.ai

[github-actions]

✅ LGTM!

Review Summary

Commits Considered (1)

• a1b64c2: feat: add factory enum

Files Processed (13)

• factory-enum/README.md (1 hunk)
• factory-enum/etc/factory-sequence-diagram.png (0 hunks)
• factory-enum/etc/factory.urm.png (0 hunks)
• factory-enum/etc/factory.urm.puml (1 hunk)
• factory-enum/pom.xml (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/App.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/ExcelProcessor.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/FileProcessor.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/FileProcessorType.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/PDFProcessor.java (1 hunk)
• factory-enum/src/test/java/com/iluwatar/factory/AppTest.java (1 hunk)
• factory-enum/src/test/java/com/iluwatar/factory/FileProcessorTest.java (1 hunk)
• pom.xml (1 hunk)

Actionable Comments (0)

Skipped Comments (0)

[github-actions]

✅ LGTM!

Review Summary

Commits Considered (1)

• d9d283d: feat: add factory enum

Files Processed (13)

• factory-enum/README.md (1 hunk)
• factory-enum/etc/factory-sequence-diagram.png (0 hunks)
• factory-enum/etc/factory.urm.png (0 hunks)
• factory-enum/etc/factory.urm.puml (1 hunk)
• factory-enum/pom.xml (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/App.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/ExcelProcessor.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/FileProcessor.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/FileProcessorType.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/PDFProcessor.java (1 hunk)
• factory-enum/src/test/java/com/iluwatar/factory/AppTest.java (1 hunk)
• factory-enum/src/test/java/com/iluwatar/factory/FileProcessorTest.java (1 hunk)
• pom.xml (1 hunk)

Actionable Comments (0)

Skipped Comments (0)

[github-actions]

✅ LGTM!

Review Summary

Commits Considered (1)

• 4359e00: feat: add factory enum

Files Processed (13)

• factory-enum/README.md (1 hunk)
• factory-enum/etc/factory-sequence-diagram.png (0 hunks)
• factory-enum/etc/factory.urm.png (0 hunks)
• factory-enum/etc/factory.urm.puml (1 hunk)
• factory-enum/pom.xml (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/App.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/ExcelProcessor.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/FileProcessor.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/FileProcessorType.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/PDFProcessor.java (1 hunk)
• factory-enum/src/test/java/com/iluwatar/factory/AppTest.java (1 hunk)
• factory-enum/src/test/java/com/iluwatar/factory/FileProcessorTest.java (1 hunk)
• pom.xml (1 hunk)

Actionable Comments (0)

Skipped Comments (0)

[github-actions]

✅ LGTM!

Review Summary

Commits Considered (1)

• bcabb8f: feat: add factory enum

Files Processed (13)

• factory-enum/README.md (1 hunk)
• factory-enum/etc/factory-sequence-diagram.png (0 hunks)
• factory-enum/etc/factory.urm.png (0 hunks)
• factory-enum/etc/factory.urm.puml (1 hunk)
• factory-enum/pom.xml (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/App.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/ExcelProcessor.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/FileProcessor.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/FileProcessorType.java (1 hunk)
• factory-enum/src/main/java/com/iluwatar/factory/PDFProcessor.java (1 hunk)
• factory-enum/src/test/java/com/iluwatar/factory/AppTest.java (1 hunk)
• factory-enum/src/test/java/com/iluwatar/factory/FileProcessorTest.java (1 hunk)
• pom.xml (1 hunk)

Actionable Comments (0)

Skipped Comments (0)

[sonarqubecloud]

Quality Gate passed

Issues
2 New issues
0 Accepted issues

Measures
0 Security Hotspots
93.3% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[letdtcode]

I think you should create new issue for this one