无法将类型为java.lang.long的对象转换为类型（模型类）

Question

我正在使用firebaseui填充recyclerview。从firebase提取数据时遇到问题。

 databaseReference.child("BatchPurchased").child("TotalCount").runTransaction(new Transaction.Handler() {
        @Override
        public Transaction.Result doTransaction(MutableData mutableData) {
            payId = "";
            Long value = mutableData.getValue(Long.class);

            if (mutableData.getValue() == null) {
                payId = "1"+"_tx";
                mutableData.setValue(1);
            } else {

                Long countset = (value + 1);
                payId = String.valueOf(countset.toString())+"_tx";
                mutableData.setValue(value + 1);

            }

            return Transaction.success(mutableData);
        }

        @Override
        public void onComplete(DatabaseError databaseError, boolean success, DataSnapshot dataSnapshot) {


            if (databaseError != null) {
                System.out.println("Firebase counter increment failed.");
            } else {
                System.out.println("Firebase counter increment succeeded.");

                DatabaseReference databaseReference1 = firebaseDatabase.getReference("User").child("BatchPurchased");
                BatchPurchased batchPurchased = new BatchPurchased(post.getUserId().toString(), userLogin.getUid().toString(), "50", post.getDecryptKey().toString(), "done", dateMy().toString(), "google_pay");                       databaseReference1.child(payId).setValue(batchPurchased);
            }
        }
    });
}]

Firebase项目结构：

模型类：

public class BatchPurchased {


    String owner_ID;
    String sender_ID;
    String price;
    String token_ID;
    String purchased_status;
    String purchased_date;
    String payment_mode;

    public BatchPurchased(String owner_ID, String sender_ID, String price, String token_ID, String purchased_status, String purchased_date, String payment_mode) {
        this.owner_ID = owner_ID;
        this.sender_ID = sender_ID;
        this.price = price;
        this.token_ID = token_ID;
        this.purchased_status = purchased_status;
        this.purchased_date = purchased_date;
        this.payment_mode = payment_mode;
    }


  public BatchPurchased() {

    }

    public String getOwner_ID() {
        return owner_ID;
    }

    public void setOwner_ID(String owner_ID) {
        this.owner_ID = owner_ID;
    }

    public String getSender_ID() {
        return sender_ID;
    }

    public void setSender_ID(String sender_ID) {
        this.sender_ID = sender_ID;
    }

    public String getPrice() {
        return price;
    }

    public void setPrice(String price) {
        this.price = price;
    }

    public String getToken_ID() {
        return token_ID;
    }

    public void setToken_ID(String token_ID) {
        this.token_ID = token_ID;
    }

    public String getPurchased_status() {
        return purchased_status;
    }

    public void setPurchased_status(String purchased_status) {
        this.purchased_status = purchased_status;
    }

    public String getPurchased_date() {
        return purchased_date;
    }

    public void setPurchased_date(String purchased_date) {
        this.purchased_date = purchased_date;
    }

    public String getPayment_mode() {
        return payment_mode;
    }

    public void setPayment_mode(String payment_mode) {
        this.payment_mode = payment_mode;
    }


}






public void dataget(){
        try {

            Query query = FirebaseDatabase.getInstance()
                    .getReference()
                    .child("User").child("BatchPurchased").;

            FirebaseRecyclerOptions<BatchPurchased> options =
                    new FirebaseRecyclerOptions.Builder<BatchPurchased>()
                            .setQuery(query,BatchPurchased.class)
                            .build();

            adapter = new FirebaseRecyclerAdapter<BatchPurchased, AllOrder>(options) {
                @NonNull
                @Override
                public AllOrder onCreateViewHolder(ViewGroup parent, int viewType) {
                    // Create a new instance of the ViewHolder, in this case we are using a custom
                    // layout called R.layout.message for each item
                    View view = LayoutInflater.from(parent.getContext())
                            .inflate(R.layout.all_order_items, parent, false);

                    return new AllOrder(view);
                }

                @Override
                protected void onBindViewHolder(AllOrder holder, int position, final BatchPurchased model) {
                    holder.bindToPost(model, MyOrdersActivity.this);
                    BatchPurchased category = model;
                    holder.setItemClickListener(new ItemClickListener() {
                        @Override
                        public void onClick(View view, int position, boolean isLongClick) {

                        }
                    });

                }
            };
            recyclerview.setAdapter(adapter);
        }catch (Exception e){
            e.printStackTrace();
        }
    }

  

例外：

     

com.google.firebase.database.DatabaseException：无法将类型为java.lang.Long的对象转换为com.example.admin.omnicam.FcmModel.BatchPurchased

从firebase提取数据时遇到的问题。请帮助解决此异常。

Answer 1

问题出在您的数据结构中。

在这段代码中，您尝试将每个子快照解析为BatchPurchased数据模型。

FirebaseRecyclerOptions<BatchPurchased> options =
                new FirebaseRecyclerOptions.Builder<BatchPurchased>()
                        .setQuery(query,BatchPurchased.class)
                        .build();

但是，不能将名为“ TotalCount”的子项解析为BatchPurchased。 考虑重组您在Firebase中存储数据的方式。