Roboguice-一个接口的两种实现

Question

My code is like this:

interface MyIntreface{
     ...
}

class A implements MyInterface{}     
class B implements MyInterface{}  

class BaseClass{
    @Inject
    MyInterface  instance;
}

class MyFirstClass extends BaseClass{
   ....
}

class MySecondClass extends BaseClass{
   ....
}

Now I want to MyFirstClass have implementation A and MySecondClass implementation B. @Named annotations seems not to work in this case. Is there any other robo-solution ?

Answer 1

This use case is impossible to implements using Roboguice. But there are two ways to resolve your problem.

• Implement provider that injects MyFirstClass and MySecondClass and then inject to provider A or B and use setter to set it in created instance

• class Baclass BaseClass{ protected abstract MyInterface extractMyInterface();
} class MyFirstClass extends BaseClass{ @Inject B instance; protected MyInterface extractMyInterface() { return instance; }
} class MySecondClass extends BaseClass{ @Inject A instance; protected MyInterface extractMyInterface() { return instance; } }

In my opinion the first one (with Provider) is much more cleaner.