Dagger 2 - two provides method that provide same interface

Question

lets say I have:

public interface Shape  {}


public class Rectangle implements Shape {

}

public class Circle implements Shape {

}

and I

Answer 1

In addition to @Named and custom qualifiers (shown in other responses), you can also use a custom qualifier with an enum parameter:

// Definition

@Qualifier
@Documented
@Retention(RetentionPolicy.RUNTIME)
public @interface ShapeType {
  ShapeTypeEnum value(); /* default ShapeTypeEnum.RECTANGLE; */
}

public enum ShapeTypeEnum {
  RECTANGLE, CIRCLE
}

// Usage

@Provides @ShapeType(ShapeTypeEnum.RECTANGLE)
public Shape provideRectangle() {
    return new Rectangle();
}

@Inject @ShapeType(ShapeTypeEnum.RECTANGLE) Shape rectangle;

This is an hybrid between @Named (which requires String keys, which is error-prone and can't be auto-completed) and custom qualifiers (which requires a file for each implementation).