Implement DAO Factory pattern

[letdtcode]

Pull Request Template

What does this PR do?

This pull request implements the DAO Factory pattern, which demonstrates how the application should be switch between three different types of data sources (H2, Mongo, Json flat file). It includes code documented implementation, comprehensive tests, detailed documentation.

Key features

• Customer: A model class presenting object that needs persistence in data source
• DAOFactory: Abstract class provides a way to get the appropriate DAO based on the data source.
• H2DataSourceFactory, MongoDataSourceFactory, FlatFileDataSourceFactory: Concrete factory which implement DAOFactory and return specific DAO Customer.
• CustomerDAO: Define CRUD operation with Customer model.
• FlatFileCustomerDAO, H2CustomerDAO, MongoCustomerDAO: Concrete DAO Customer which implement CRUD operation with data source.

Related Issue

Closes #1270

[github-actions]

PR Summary

This PR implements the DAO Factory pattern, providing flexible data access by switching between H2, Mongo, and JSON flat file data sources. It includes a Customer model, DAOFactory abstract class, concrete factories (H2DataSourceFactory, MongoDataSourceFactory, FlatFileDataSourceFactory), CustomerDAO interface, and concrete DAO implementations. Comprehensive tests and documentation are also included.

Changes

File	Summary
dao-factory/README.md	This file provides a comprehensive guide to the DAO Factory pattern, including its intent, real-world examples, a class diagram, a programmatic example in Java, usage scenarios, benefits, trade-offs, and related design patterns. It also includes references and credits.
dao-factory/etc/dao-factory.png	New file: Class diagram for the DAO Factory pattern.
dao-factory/etc/dao-factory.puml	New file: PlantUML class diagram for the DAO Factory pattern.
dao-factory/pom.xml	New file: Maven project configuration file for the DAO Factory pattern implementation. It includes dependencies for H2 database, MongoDB driver, Gson, and testing frameworks.
dao-factory/src/main/java/com/iluwatar/daofactory/App.java	This Java class demonstrates the usage of the DAO Factory pattern. It performs CRUD operations on Customer objects using H2, MongoDB, and JSON flat file data sources.
dao-factory/src/main/java/com/iluwatar/daofactory/CustomException.java	New file: Custom exception class for handling errors in the DAO Factory pattern implementation.
dao-factory/src/main/java/com/iluwatar/daofactory/Customer.java	New file: A generic POJO class representing a customer, designed to work with various ID types for different persistence systems.
dao-factory/src/main/java/com/iluwatar/daofactory/CustomerDAO.java	New file: Interface defining CRUD operations for the Customer model. Provides an abstraction layer for data access.
dao-factory/src/main/java/com/iluwatar/daofactory/DAOFactory.java	New file: Abstract factory class for creating concrete DAO factories for different data sources.
dao-factory/src/main/java/com/iluwatar/daofactory/DAOFactoryProvider.java	New file: Utility class providing concrete DAOFactory instances based on the data source type.
dao-factory/src/main/java/com/iluwatar/daofactory/DataSourceType.java	New file: Enumeration defining supported data source types (H2, Mongo, FlatFile).
dao-factory/src/main/java/com/iluwatar/daofactory/FlatFileCustomerDAO.java	New file: Implementation of CustomerDAO using JSON flat files for data persistence. Handles file I/O and JSON serialization.
dao-factory/src/main/java/com/iluwatar/daofactory/FlatFileDataSourceFactory.java	New file: Concrete factory for creating FlatFileCustomerDAO instances.
dao-factory/src/main/java/com/iluwatar/daofactory/H2CustomerDAO.java	New file: Implementation of CustomerDAO using an in-memory H2 database. Handles database interactions.
dao-factory/src/main/java/com/iluwatar/daofactory/H2DataSourceFactory.java	New file: Concrete factory for creating H2CustomerDAO instances.
dao-factory/src/main/java/com/iluwatar/daofactory/MongoCustomerDAO.java	New file: Implementation of CustomerDAO using MongoDB for data persistence. Handles MongoDB interactions.
dao-factory/src/main/java/com/iluwatar/daofactory/MongoDataSourceFactory.java	New file: Concrete factory for creating MongoCustomerDAO instances.
dao-factory/src/main/resources/logback.xml	New file: Logback configuration file for setting up logging.
dao-factory/src/test/java/com/iluwatar/daofactory/AppTest.java	New file: Unit tests for the App class, verifying CRUD operations.
dao-factory/src/test/java/com/iluwatar/daofactory/DAOFactoryTest.java	New file: Unit tests for the DAOFactory class, verifying the creation of different DAO implementations.
dao-factory/src/test/java/com/iluwatar/daofactory/FlatFileCustomerDAOTest.java	New file: Unit tests for the FlatFileCustomerDAO class, covering various scenarios like saving, updating, deleting, and finding customers.
dao-factory/src/test/java/com/iluwatar/daofactory/H2CustomerDAOTest.java	New file: Unit tests for the H2CustomerDAO class, covering various scenarios like saving, updating, deleting, and finding customers.
dao-factory/src/test/java/com/iluwatar/daofactory/MongoCustomerDAOTest.java	New file: Unit tests for the MongoCustomerDAO class, covering various scenarios like saving, updating, deleting, and finding customers.
pom.xml	The dao-factory module was added to the project.

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autogenerated by presubmit.ai

[github-actions]

✅ LGTM!

Review Summary

Commits Considered (8)

• f9263cc: fix SonarQube
• 7c83fec: add license
• 0a24bfd: fix: unit test pipeline
• abd7ef8: fix: h2 inmemory database to pass CI
• 525ad3f: doc: add document for dao-factory
• 2960794: test: Add unit test dao-factory
• fd0f855: feat: done implement dao factory
• 50fbd10: feat: implement dao factory

Files Processed (24)

• dao-factory/README.md (1 hunk)
• dao-factory/etc/dao-factory.png (0 hunks)
• dao-factory/etc/dao-factory.puml (1 hunk)
• dao-factory/pom.xml (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/App.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/CustomException.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/Customer.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/CustomerDAO.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/DAOFactory.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/DAOFactoryProvider.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/DataSourceType.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/FlatFileCustomerDAO.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/FlatFileDataSourceFactory.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/H2CustomerDAO.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/H2DataSourceFactory.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/MongoCustomerDAO.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/MongoDataSourceFactory.java (1 hunk)
• dao-factory/src/main/resources/logback.xml (1 hunk)
• dao-factory/src/test/java/com/iluwatar/daofactory/AppTest.java (1 hunk)
• dao-factory/src/test/java/com/iluwatar/daofactory/DAOFactoryTest.java (1 hunk)
• dao-factory/src/test/java/com/iluwatar/daofactory/FlatFileCustomerDAOTest.java (1 hunk)
• dao-factory/src/test/java/com/iluwatar/daofactory/H2CustomerDAOTest.java (1 hunk)
• dao-factory/src/test/java/com/iluwatar/daofactory/MongoCustomerDAOTest.java (1 hunk)
• pom.xml (2 hunks)

Actionable Comments (0)

Skipped Comments (0)

[github-actions]

✅ LGTM!

Review Summary

Commits Considered (1)

• 9afad6d: add pom.xml

Files Processed (24)

• dao-factory/README.md (1 hunk)
• dao-factory/etc/dao-factory.png (0 hunks)
• dao-factory/etc/dao-factory.puml (1 hunk)
• dao-factory/pom.xml (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/App.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/CustomException.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/Customer.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/CustomerDAO.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/DAOFactory.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/DAOFactoryProvider.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/DataSourceType.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/FlatFileCustomerDAO.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/FlatFileDataSourceFactory.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/H2CustomerDAO.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/H2DataSourceFactory.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/MongoCustomerDAO.java (1 hunk)
• dao-factory/src/main/java/com/iluwatar/daofactory/MongoDataSourceFactory.java (1 hunk)
• dao-factory/src/main/resources/logback.xml (1 hunk)
• dao-factory/src/test/java/com/iluwatar/daofactory/AppTest.java (1 hunk)
• dao-factory/src/test/java/com/iluwatar/daofactory/DAOFactoryTest.java (1 hunk)
• dao-factory/src/test/java/com/iluwatar/daofactory/FlatFileCustomerDAOTest.java (1 hunk)
• dao-factory/src/test/java/com/iluwatar/daofactory/H2CustomerDAOTest.java (1 hunk)
• dao-factory/src/test/java/com/iluwatar/daofactory/MongoCustomerDAOTest.java (1 hunk)
• pom.xml (1 hunk)

Actionable Comments (0)

Skipped Comments (0)

[sonarqubecloud]

Quality Gate passed

Issues
3 New issues
0 Accepted issues

Measures
0 Security Hotspots
83.8% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud