Java generics and typecasting

Question

I have a badly created container object that holds together values of different java types(String, Boolean etc ..)

public class BadlyCreatedClass {
    public Object get(String property) {
        ...;
    }
};

And we extract values from it in this way

String myStr = (String) badlyCreatedObj.get("abc");
Date myDate = (Date) badlyCreatedObj.get("def");

I am forced to write some new code using this object and I am trying to see if there is clean way to do this. More specifically which method from the below is preferred ?

Explicit Cast

String myStr = (String) badlyCreatedObj.get("abc")
Date myDate = (Date) badlyCreatedObj.get("def");

Using generic cast

public <X> X genericGet(String property) {

}

public String getString(String property) { 
return genericGet(property); 
}

public Date getDate(String property) { 
return genericGet(property); 
}

Using Class.cast

<T> T get(String property, Class<T> cls) {
    ;
}

I have gone through several related questions on SO Java generic function: how to return Generic type , Java generic return type all of them seem to say the such typecasting is dangerous, ALthough I dont see much difference between the three, given this which method would you prefer ?

Thanks

Answer 1

To give a quick answer, without going in deep about good-programming-practice...

I would use:

private <X> X genericGet(String property) {

}

public String getString(String property) { 
//... checks on property (String specific)...
Object obj = genericGet(property);
//... checks if obj is what is expected and if good return it
return obj; 
}

public Date getDate(String property) { 
//... checks on property (Date specific)...
Object obj = genericGet(property);
//... checks if obj is what is expected and if good return it
return obj
}

make notice to the private genericGet. This way I can check if the get property is what I m waiting to receive and handle it in a correct way.

I could add checks in the getString depends on the property to make sure that the answer will be a String object.

I could do other checks for getDate in property to make sure it will be a date as will be returned.

Etc...