Efficiently Handling Complex Conditional Business Logic in Kotlin with Spring Boot 3 & Gradle

I am currently working on a Spring Boot 3 application with Kotlin and Gradle, and I've encountered a challenge that I think many of you might find interesting. My application deals with complex business logic that involves numerous conditional operations. The challenge is to implement this logic in a way that is both efficient and maintainable.

Here's a simplified version of what I am trying to achieve:

• I have multiple sets of conditions that determine the business logic flow. Each set of conditions can lead to different outcomes or actions.
• These conditions are not just simple if-else statements; they are quite intricate and involve various aspects of the application's data model.
• I am looking for a design pattern or approach in Kotlin that would help manage this complexity elegantly. Ideally, the solution should be easy to read and maintain, as other team members will also work on this codebase.

Here are some specific questions:

1. Are there any Kotlin-specific features or idioms that are particularly useful for handling complex conditional logic?
2. How can I leverage Spring Boot 3's features to aid in this implementation?
3. What are the best practices in Gradle to manage dependencies that might be needed for this solution? Any insights or examples would be greatly appreciated.

I use the "when" construct, which makes it easier to write conditions, but also becomes cumbersome when you need to check a lot of nested conditions.

It is hard to say without code what pattern should be used. However, these words remind me that Strategy pattern can be used:

Each set of conditions can lead to different outcomes or actions

You put your conditions in some method and then when decision is made about what strategy should be used, you can apply it.

I am sorry I do not know Kotlin, so let me show an example via C#.

This is the method which has complex logic like you have

public DataProviderType GetDataProviderType()
{
    if (...)
         return DataProviderType.Csv;
         
    return DataProviderType.Api
}

These are enums which corresponds to the strategy:

public enum DataProviderType
{
    RabbitMq, Api, Csv
}

And this is a factory of strategies:

public class DataProviderFactory
{
    private Dictionary<DataProviderType, IDataProvider> _dataProviderByType
        = new Dictionary<DataProviderType, IDataProvider>()
        {
            { DataProviderType.RabbitMq, new RabbitMQDataProvider() },
            { DataProviderType.Api, new ApiDataProvider() },
            { DataProviderType.Csv, new CsvDataProvider() },
        };

    public IDataProvider GetInstanceByType(DataProviderType dataProviderType) =>
        _dataProviderByType[dataProviderType];
}

And then you can get your strategy like this:

DataProviderType dataProviderType = GetDataProviderType();
DataProviderFactory dataProviderFactory = new();
IDataProvider dataProvider = dataProviderFactory
   .GetInstanceByType(DataProviderType.Api);
string data = dataProvider.Get();