Question

public class Widget {
    @Inject
    Fizz fizz;

    public Widget(Fizz fizz) {
        super();

        setFizz(fizz);
    }

    public void setFizz(Fizz fizz) {
        this.fizz = fizz;
    }
}

Is this a Guice anti-pattern?!?!

If I say “fizz will be injected (via @Inject)”, but then I allow a constructor and setter to accept a fizz, is this unnecessarily-redundant? Could it cause a conflict with Guice’s injector?

I guess I’m confused as to:

• When you should annotate a property with @Inject, vs.
• When you should “inject” the property yourself via constructor/getter

Any thoughts? Thanks in advance!

Answer 1

Why not use something like this (i.e. use constructor injection) ?

public class Widget {
    private Fizz fizz;

    @Inject
    public Widget(Fizz fizz) {
        super();

        this.fizz = fizz;
    }

}

See also http://code.google.com/p/google-guice/wiki/Injections