• Language: Java17
• Build tool: Gradle
• Framework: SpringBoot 3
• Libs: OpenCSV, Logback
• Test: JUnit 5

Make sure you have JDK17 installed on machine, and switch to Java17 if got multiple Java versions.

• JDK17 download link: https://www.oracle.com/java/technologies/javase/jdk17-archive-downloads.html

./gradlew clean build

2.1. Run built jar:

java -jar build/libs/floenergy-assignment-1.0-SNAPSHOT.jar

2.2. Enter path to input CSV file when asked Please enter CSV file path:
(e.g: src/test/resources/input/example.csv)

Java is a mature OOP programming language with one of largest Dev communities. Some of its advantages:

• High-performant compare to other general purpose languages.
• Compile-time safety and platform independent.
• Strict syntax and robust test framework.

Spring framework helps us develop and manage code with production-grade quality via features like dependency injection, managed configuration properties (via YML file), DB support (Spring Data/JPA), AOP, integration tests (via SpringBootTest),...

As this is a small half day assignment, not much of effort to redesign/restructure code with a fancy architecture. Basically this is simply what I applied:

• Split code into smaller classes like Factory, Processor.
• Within a class, separate code into multiple methods and expose some configurations to prop file (application.yml).

• Splitting code into smaller classes, methods will help engineers separate code logic, therefore code is easier to maintain and test.
• It also helps reduce cognitive load for readers while going through the code, they can focus more on a specific part of code.
• Exposing some configurable variables to properties file assists in better config management and seamless value updates.

• Factory design pattern (in MeterReadingFactory.java), helps encapsulate object creation and improve testability.
• DRY (Don't Repeat Yourself) (splitting smaller classes methods), helps achieve cleaner code.
• Centralized log pattern (using Logback), helps bring more consistent and useful logs.
• IoC (Inversion of Control): Framework (Spring) automatically manages and creates dependencies via Bean ( like Nem12CsvProcessor) so that our code is more testable and maintainable.

Improvements:

• Support concurrent processing of file (if order does not matter) to improve processing time
• Support processing multiple files (input can be folder)
• Add some NEM12 validations to make app more robust

Can use Python to write a script as well. Python would help code less verbose and easier to read. However in the long run, Python is less performant and harder to maintain than Java.