In HK2 the basic example code for configuring injection is this (within a class that extends AbstractBinder
:
bind(BuilderHelper
.link(FooImpl.class) // the class of the object to be injected
.to(FooInterface.class) // identifies what @Inject fields to link to
.build());
This causes HK2 to call the constructor FooImpl()
when it needs to create a FooInterface
.
What if FooImpl doesn't have a constructor?
FooImpl.getInstance()
fooFactory.create()
I see that ResourceConfig
has a method bind(FactoryDescriptors factoryDescriptors)
but it is not clear to me what the idiom is for building a FactoryDescriptors
object, and have not been able to find any examples online.
While I still can't see a way to do it using the BuilderHelper EDSL (it appears this is overkill for the common case too), the following works:
bindFactory(FooFactory.class)
.to(FooInterface.class);
This requires that FooFactory
is an implementation of Factory<FooInterface>
, so you need a facade around any existing factory you have. I did it as a private inner class where I needed it.
private static class FooFactory implements Factory<FooInterface> {
@Override
public void dispose(FooInterface foo) {
// meh
}
@Override
public FooInterface provide() {
return SomeFactory.getInstance();
}
}