Java: Is there a way to get methods with different return types in a enum?

I know that its not possible to use generics with Enums but im searching for a way to implement a method for a enum with different return types.

For example I have following enum:

enum TestEnum {

    TEST_INTEGER() {
        @Override
        public Integer getValue() {
            return 123;
        }
    },

    TEST_STRING() {
        @Override
        public String getValue() {
            return "Test";
        }
    };

    public abstract Object getValue();
}

In this case TEST_INTEGER and TEST_STRING are implementations of TestEnum. Thats why the method getValue() has the return type Object and not Integer or String when the getValue() is invoked. That means in each case I have to cast to the concerning Classtype.

Is there any better way to get diretly the different Classtypes?