Getting 'Failed to bounce to type' exception even after giving the accurate firebase reference. Please see details

Question

I'm developing an app which is using Firebase as BaaS.

The problem is that I'm getting com.firebase.client.FirebaseException: Failed to bounce to type at com.firebase.client.DataSnapshot.getValue(DataSnapshot.java:183) at com.abc.xyz.MainActivity$2.onDataChange(MainActivity.java:119) even after giving the right firebase reference. Another notable line in the stacktrace is Caused by: com.fasterxml.jackson.databind.JsonMappingException: Conflicting setter definitions for property "colorFilter": android.widget.ImageView#setColorFilter(1 params) vs android.widget.ImageView#setColorFilter(1 params).

Here's Firebase reference: Firebase mFirebaseRef = new Firebase("https://appname.firebaseio.com/users");

Here's my piece of code:

    mFirebaseRef.addValueEventListener(new ValueEventListener() {
                    @Override
                    public void onDataChange(DataSnapshot snapshot) {
                        System.out.println("There are " + snapshot.getChildrenCount() + " blog posts");
                        for (DataSnapshot postSnapshot : snapshot.getChildren()) {
    //error on this line 
UsersDataFromFirebase post = postSnapshot.getValue(UsersDataFromFirebase.class);

                            View nameView = navigationView.getHeaderView(0);
                            userName = (TextView) nameView.findViewById(R.id.userName);
                            userName.setText(post.getUserName());

                            System.out.println(post.getUserName());
                            System.out.println(post.getUserEmail());

    //                        View emailView = navigationView.getHeaderView(0);
    //                        userEmail = (TextView) emailView.findViewById(R.id.userEmail);
    //                        userEmail.setText();

                            userImageUrl = (URL) authData.getProviderData().get("profileImageUrl");

                            String userImageUrlString = userImageUrl.toString();

                            URL url = null;
                            try {
                                url = new URL(userImageUrlString);
                            } catch (MalformedURLException e) {
                                e.printStackTrace();
                            }
                            try {
                                image = BitmapFactory.decodeStream(url.openConnection().getInputStream());
                            } catch (IOException e) {
                                e.printStackTrace();
                            }

                            View imageView = navigationView.getHeaderView(0);
                            userImage = (ImageView) imageView.findViewById(R.id.userImage);
                            userImage.setImageBitmap(image);

                        }
                    }

                    @Override
                    public void onCancelled(FirebaseError firebaseError) {
                        System.out.println("The read failed: " + firebaseError.getMessage());
                        Toast.makeText(getBaseContext(), firebaseError.getMessage(), Toast.LENGTH_LONG).show();
                    }
                });

            } else {
                android.app.AlertDialog.Builder builder = new android.app.AlertDialog.Builder(MainActivity.this);
                builder.setTitle("No internet connection!");
                builder.setMessage("Please connect to the internet.");
                builder.setPositiveButton("Open Settings", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialogInterface, int i) {
                        Intent intent = new Intent(Settings.ACTION_SETTINGS);
                        startActivity(intent);
                        //progressBar.setVisibility(View.INVISIBLE);
                    }
                });
                builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialogInterface, int i) {
                        //progressBar.setVisibility(View.INVISIBLE);
                    }
                });
                builder.show();
            }

Here's UsersDataFromFirebase.java file's code:

public class UsersDataFromFirebase {
    private String userName;
    private String userEmail;
    private ImageView userImage;

    public UsersDataFromFirebase() {
        // empty default constructor, necessary for Firebase to be able to deserialize blog posts
    }

    public String getUserName() {
        return userName;
    }

    public String getUserEmail() {
        return userEmail;
    }

    public ImageView getUserImage() {
        return userImage;
    }

}

As Firebase is something very new to me, I'm unable to figure out what's going wrong here.

Please let me know.

Thanks in advance!

Answer 1

You've included a ImageView in your Java class, which Jackson/Firebase doesn't know how to serialize data to.

The solution is to tell Firebase/Jackson to ignore the ImageView when it reads the object from/writes it to JSON.

public class UsersDataFromFirebase {
    private String userName;
    private String userEmail;
    private ImageView userImage;

    public UsersDataFromFirebase() {
        // empty default constructor, necessary for Firebase to be able to deserialize blog posts
    }

    public String getUserName() { return userName; }

    public String getUserEmail() { return userEmail; }

    @JsonIgnore    
    public ImageView getUserImage() { return userImage; }
}

Note that this is covered in my answer to this question: Why do I get "Failed to bounce to type" when I turn JSON from Firebase into Java objects?