Nsryjdtyk

Let's first state the (base) classes that are part of this:

// the data class. This contains our values

public class Data<T extends Annotation> {

    public transient final T info; // gson ignores transients

    public Data(Class<T> annotation) { info = getClass().getAnnotation(annotation); }

}



// the manager class, this contains numerous Data's

public class Manager<T> {

    protected final ArrayList<T> collection = new ArrayList<T>();

    public Collection<T> GetCollection() { return collection; }

}

Now suppose I've implemented the above classes in the following Manner:

// my implemented manager. It contains a bunch of MyBase objects

public class MyManager extends Manager<MyBase> {

    public MyManager() {

        collection.add(new MyCustomBase());

        // some more...

    }

}



public class MyBase extends MyData {

    // some stuff for my base, such as various methods for calculating and rendering

}



public MyData extends Data<MyData.MyInterface> {

    public String foo;

    MyData() {

        super(MyData.MyInterface.class);

        foo = info.foo(); // handle our interface variables, since interfaces cannot be directly modified

    }



    @Retention

    public @interface MyInterface {

        String foo();

    }

For sake of hopefully understandable code, my custom base looks like this:

@MyData.MyInterface(foo = "bar")

public class CustomBase extends MyBase {

    // other various methods for rendering and calculating, some events in here too

}

Now, in GSON, I'd like to print out the information from MyData. This is the way I've gone about trying to do it:

public class Config {

    // store the 'Managers' which we want to save the data of inside of an arrayList, and then iterate through them and their contents for 'Data', then just save it.

//...

Gson gson = new GsonBuilder().setPrettyPrinting().create();

PrintWriter writer = new PrintWriter(myJSON);

for (Manager m : managerList) {

    for (Object o : m.GetCollection()) {

        Data d = (Data) o;

        // expected result, a json with "foo": bar

        writer.println(gson.toJson(d)); // this doesn't work, throws a stack overflow

    }



    writer.close();

}

Unfortunately, this approach is not working. It, for some weird reason, throws a Stack Overflow. What might be a better approach for this?

Edit: I won't handle the interface directly since foo, or any other values will change during the course of the program.

I've managed to avoid this issue by making use of the @Expose annotation:

public MyData {

    @Expose public String foo;

}

Then, when creating the Gson using GsonBuilder, just use excludeFieldWithoutExposeAnnotation().