DatabaseException：无法将java.lang.String类型的对象转换为com.example.chat.groupConv类型

Question

我是android初学者，我无法解决此崩溃 DatabaseException：无法将java.lang.String类型的对象转换为com.example.chat.groupConv类型

这是我的代码，仅打印第一个日志消息，应用程序崩溃并抛出该DataBaseException

  public void onStart() {
    super.onStart();
    Query conversationQuery = mConvDatabase.orderByChild("time");
    Log.v("conversationQuery", String.valueOf(conversationQuery));
    FirebaseRecyclerAdapter<groupConv, ConvViewHolder> adapter =
            new FirebaseRecyclerAdapter<groupConv, ConvViewHolder>(

                    groupConv.class,
                    R.layout.users_single_layout,
                    ConvViewHolder.class,
                    conversationQuery
            ) {

                @Override
                protected void populateViewHolder(final ConvViewHolder convViewHolder, final groupConv groupConv, int i) {

                    Query lastMessageQuery = mConvDatabase.limitToLast(1);
                    Log.v("populateViewHolder","populateViewHolder");
                    lastMessageQuery.addValueEventListener(new ValueEventListener() {
                        @Override
                        public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
                            Log.v("onDataChange","onDataChange");
                            //Messages msg =dataSnapshot.getValue(Messages.class);
                            //String data = msg.getMessage();
                            String data =  dataSnapshot.child("message").getValue(String.class);
                            convViewHolder.setMessage(data, groupConv.isSeen());
                        }

                        @Override
                        public void onCancelled(@NonNull DatabaseError databaseError) {

                        }
                    });

groupConv类

public class groupConv {
    private String message, type;
    private long time;
    private boolean seen;
    private String sender;
    private String reciever0;

    public groupConv() { }

    public groupConv(String sender) {this.sender = sender; }

    public groupConv(String message, String type, long time, boolean seen,String sender, String to) {
        this.message = message;
        this.type = type;
        this.time = time;
        this.seen = seen;
        this.sender = sender;
        reciever0 = to;
    }

    public String getFrom() { return sender; }

    public void setFrom(String sender) { this.sender = sender; }

    public String getMessage() { return message; }

    public void setMessage(String message) { this.message = message; }

    public String getType() { return type; }

    public void setType(String type) { this.type = type; }

    public long getTime() { return time; }

    public void setTime(long time) { this.time = time; }

    public boolean isSeen() { return seen; }

    public void setSeen(boolean seen) { this.seen = seen; }

    public String getSender() { return sender; }

    public void setSender(String sender) { this.sender = sender; }

    public String getReciever0() { return reciever0; }

    public void setReciever0(String reciever0) { this.reciever0 = reciever0; }
}

火力基地

希望任何人都可以帮助我！