MarkHmnv / autumn-framework

Autumn Framework is a light-weight, educational project inspired by the Spring Framework. It was created with the purpose of understanding how Spring works under the hood.

Autumn Framework

Autumn Framework is a light-weight, educational project inspired by the Spring Framework. It was created with the purpose of understanding how Spring works under the hood.

Features

• Simple, but powerful IOC container with Singleton and Prototype scopes support
• Dependency Injection using @Inject annotation
• Component scan using @Injectable annotation with scopes support
• Inject properties from application.properties using @InjectProperty annotation
• Straightforward Java configuration
• Flexible object configurators and proxy configurators
• Generates warnings when deprecated classes are called
• Helps to understand Spring Core concepts in a simplified manner

Getting Started

Configuration

public class JavaConfig implements Config {
...

    @Override
    public <T> Class<? extends T> getImplClass(Class<T> ifc) {
        return ifc2ImplClass.computeIfAbsent(ifc, aClass -> {
            Set<Class<? extends T>> classes = scanner.getSubTypesOf(ifc)
                    .stream()
                    .filter(clazz -> clazz.isAnnotationPresent(Injectable.class))
                    .collect(Collectors.toSet());
            ...
        });
    }
}

Annotations

Create Injectable classes with @Injectable and inject dependencies using @Inject.

import com.markhmnv.autumnframework.annotation.Inject;

@Injectable
public class DemoService {
    @Inject
    private DemoRepository demoRepository;

    ...
}

Or use @RequiredArgsConstructor from Lombok

import lombok.RequiredArgsConstructor;

@Injectable
@RequiredArgsConstructor
public class DemoService {
    private final DemoRepository demoRepository;

    ...
}

Inject properties from application.properties using @InjectProperty.

@Injectable
public class DemoService {
    @InjectProperty
    private String secret;
    ...
}

ApplicationContext and Startup

Create an instance of ApplicationContext via AutumnApplication.run(). After that, simply call context.getObject() to get full-featured objects.

public class Demo {
    public static void main(String[] args) {
        ApplicationContext context = AutumnApplication.run(Demo.class);
        DemoController demoController = context.getObject(DemoController.class);
        ...
    }
}