Implement Thread-Pool Executor pattern

[yybmion]

Pull Request Template

What does this PR do?

This PR implements the Thread-Pool Executor pattern, which demonstrates how a pool of worker threads can be used to execute tasks concurrently. It includes a complete implementation with a hotel front desk example, comprehensive tests, and detailed documentation.

Key Features

• Adds FrontDeskService class that manages a thread pool for hotel employees
• Implements GuestCheckInTask (Runnable) for regular guest check-ins
• Implements VipGuestCheckInTask (Callable) for VIP guest check-ins with results
• Includes comprehensive tests verifying correct behavior under load and proper shutdown
• Provides detailed README with pattern explanation, class diagrams, and examples

Related Issue

Closes #3226

[github-actions]

PR Summary

This PR implements the Thread-Pool Executor pattern using a hotel front desk example. It includes a FrontDeskService class managing a thread pool, GuestCheckInTask for regular guests, and VipGuestCheckInTask for VIP guests. Comprehensive tests and a detailed README with diagrams are also provided.

Changes

File	Summary
pom.xml	The thread-pool-executor module was added to the project.
thread-pool-executor/README.md	A comprehensive README was added, explaining the Thread-Pool Executor pattern, including real-world examples, class diagrams, and a Java code example using a hotel front desk scenario.
thread-pool-executor/etc/thread-pool-executor.urm.png	New file.
thread-pool-executor/etc/thread-pool-executor.urm.puml	PlantUML class diagram for the Thread-Pool Executor pattern was added.
thread-pool-executor/pom.xml	The pom.xml file for the thread-pool-executor module was added, defining dependencies and build configurations.
thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/App.java	This class demonstrates the Thread-Pool Executor pattern by simulating a hotel front desk managing guest check-ins using ExecutorService.
thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/FrontDeskService.java	This class manages a thread pool of employees to handle guest check-ins, using ExecutorService for task submission and management.
thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/GuestCheckInTask.java	This class represents a regular guest check-in task, implementing Runnable to perform the check-in process.
thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/VipGuestCheckInTask.java	This class represents a VIP guest check-in task, implementing Callable to perform the check-in and return a result.
thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/AppTest.java	This test class verifies that the main application class starts without throwing any exceptions.
thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/FrontDeskServiceTest.java	This test class contains multiple tests for the FrontDeskService, covering various scenarios like task submission, shutdown, and concurrent task execution.
thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/GuestCheckInTaskTest.java	This test class verifies that the GuestCheckInTask executes correctly and captures the current thread name.
thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/VipGuestCheckInTaskTest.java	This test class verifies that the VipGuestCheckInTask returns the expected result string after execution.

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autogenerated by presubmit.ai

[github-actions]

✅ LGTM!

Review Summary

Commits Considered (1)

• b83a609: feat: Implement Thread-Pool Executor pattern

• Add implementation of Thread-Pool Executor pattern using hotel front desk example

• Include unit tests

• Create detailed README with pattern explanation and examples

• Add Java source code with appropriate Javadoc comments

Closes #3226

Files Processed (13)

• pom.xml (1 hunk)
• thread-pool-executor/README.md (1 hunk)
• thread-pool-executor/etc/thread-pool-executor.urm.png (0 hunks)
• thread-pool-executor/etc/thread-pool-executor.urm.puml (1 hunk)
• thread-pool-executor/pom.xml (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/App.java (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/FrontDeskService.java (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/GuestCheckInTask.java (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/VipGuestCheckInTask.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/AppTest.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/FrontDeskServiceTest.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/GuestCheckInTaskTest.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/VipGuestCheckInTaskTest.java (1 hunk)

Actionable Comments (0)

Skipped Comments (0)

[e5LA]

cosmetic: why not putting it in alphabetic order? 😉 also, indentation seems off

[yybmion]

Thanks for your review!
I currently working on fixing the Sonarqube issues in the code, so I'll address these formatting problems too.

[github-actions]

✅ LGTM!

Review Summary

Commits Considered (1)

• 7f2f1fd: feat: Implement Thread-Pool Executor pattern

• Add implementation of Thread-Pool Executor pattern using hotel front desk example

• Include unit tests

• Create detailed README with pattern explanation and examples

• Add Java source code with appropriate Javadoc comments

Closes #3226

Files Processed (13)

• pom.xml (1 hunk)
• thread-pool-executor/README.md (1 hunk)
• thread-pool-executor/etc/thread-pool-executor.urm.png (0 hunks)
• thread-pool-executor/etc/thread-pool-executor.urm.puml (1 hunk)
• thread-pool-executor/pom.xml (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/App.java (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/FrontDeskService.java (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/GuestCheckInTask.java (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/VipGuestCheckInTask.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/AppTest.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/FrontDeskServiceTest.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/GuestCheckInTaskTest.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/VipGuestCheckInTaskTest.java (1 hunk)

Actionable Comments (0)

Skipped Comments (0)

[github-actions]

✅ LGTM!

Review Summary

Commits Considered (1)

• 3d8fa01: feat: Implement Thread-Pool Executor pattern

• Add implementation of Thread-Pool Executor pattern using hotel front desk example

• Include unit tests

• Create detailed README with pattern explanation and examples

• Add Java source code with appropriate Javadoc comments

Closes #3226

Files Processed (13)

• pom.xml (1 hunk)
• thread-pool-executor/README.md (1 hunk)
• thread-pool-executor/etc/thread-pool-executor.urm.png (0 hunks)
• thread-pool-executor/etc/thread-pool-executor.urm.puml (1 hunk)
• thread-pool-executor/pom.xml (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/App.java (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/FrontDeskService.java (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/GuestCheckInTask.java (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/VipGuestCheckInTask.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/AppTest.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/FrontDeskServiceTest.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/GuestCheckInTaskTest.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/VipGuestCheckInTaskTest.java (1 hunk)

Actionable Comments (0)

Skipped Comments (0)

[github-actions]

✅ LGTM!

Review Summary

Commits Considered (1)

• 3ac5ce7: feat: Implement Thread-Pool Executor pattern

• Add implementation of Thread-Pool Executor pattern using hotel front desk example

• Include unit tests

• Create detailed README with pattern explanation and examples

• Add Java source code with appropriate Javadoc comments

Closes #3226

Files Processed (13)

• pom.xml (1 hunk)
• thread-pool-executor/README.md (1 hunk)
• thread-pool-executor/etc/thread-pool-executor.urm.png (0 hunks)
• thread-pool-executor/etc/thread-pool-executor.urm.puml (1 hunk)
• thread-pool-executor/pom.xml (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/App.java (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/FrontDeskService.java (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/GuestCheckInTask.java (1 hunk)
• thread-pool-executor/src/main/java/com/iluwatar/threadpoolexecutor/VipGuestCheckInTask.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/AppTest.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/FrontDeskServiceTest.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/GuestCheckInTaskTest.java (1 hunk)
• thread-pool-executor/src/test/java/com/iluwatar/threadpoolexecutor/VipGuestCheckInTaskTest.java (1 hunk)

Actionable Comments (0)

Skipped Comments (0)

[sonarqubecloud]

Quality Gate passed

Issues
4 New issues
0 Accepted issues

Measures
0 Security Hotspots
90.6% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud