Android Firebase 2.4 IllegalStateException using new ref.updateChildren()

Question

When using Firebase 2.4 ref.updateChildren() with HashMap, other than HashMap (e.g. HashMap)

Answer 1

As in the code snippet from the Official Firebase Blog to avoid this issue one has to re-write custom structure like this:

Map<String, String> newPost = new HashMap<String, String>();
newPost.put("title", "New Post");
newPost.put("content", "Here is my new post!");

And then put it instead of custom data model:

Map<String, Object> updatedUserData = new HashMap<String, Object>();
updatedUserData.put("users/posts/" + newPostKey, true);
updatedUserData.put("posts/" + newPostKey, newPost);

Using custom data model instead of newPost causes IllegalStateException.

Answer 2

On your last question:

Is there a way to pass custom HashMap like HashMap to ref.updateChildren() ?

The Firebase SDK for Android/Java doesn't support directly passing POJOs (like your User class) into updateChildren().

But what you can do is convert the POJO into a Map with:

Map<String, Object> userMap = new ObjectMapper().convertValue(user, Map.class);

Then you can put the map of values into the values that you're passing into updateChildren():

updates.put("users/"+uid, userMap);
updates.put("lists/"+uid+"/mine, "value");

ref.updateChildren(updates);