Which DI would you suggest Constructor-based or setter-based DI?

1.	Which DI would you suggest Constructor-based or setter-based DI?
Answer» Since you can mix both, Constructor- and Setter-based DI, it is a good rule of thumb to use constructor arguments for mandatory dependencies and setters for optional dependencies. Note that the use of a Required annotation on a setter can be used to make setters required dependencies.

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