CODEWITHSUNDEEP
javaandroidcountfirebase
nothingness
nothingness

Reputation: 694

Count all values Firebase Java API

I'm trying to count all the values in my firebase database in Java. But its not working, I have looked at some tutorials for this but haven't found any for Java programmers.

Here is my database:

Language
  German
    Message
      -Jf6ShYy7niHrqg_x4Tc: "Tomorrow is very windy"
      -Jf9v0xHAxINUUANrORU: "Today is very windy and rainy"

Here is my code, note the line I attempted to use count max value:

    Firebase f = new Firebase("https://myapp.firebaseio.com/Language/German/Message/");             
    f.addValueEventListener(new ValueEventListener() {

        public void onDataChange(DataSnapshot snapshot) {
            disp_msg = (TextView)findViewById(R.id.display_msg);
            //disp_msg.setText(snapshot.getValue().toString());
            Iterable<DataSnapshot> ds = snapshot.getChildren();
            Iterator<DataSnapshot> ids = ds.iterator();
            Map<String, Object> newPost = (Map<String, Object>) ids.next().getValue();
            String msg = newPost.get("pubMsg").toString();
            disp_msg.setText(msg.toString());

            //The line below does not work getting the maximum values
            int maxValueInMap=(Collections.max(newPost.values().toString())); 

        }

This is the error I get at the max function from Collections:

The method max(Collection) in the type Collections is not applicable for the arguments (String)

Does anyone know how to solve this problem in Java, Thanks in advance.

Upvotes: 5

Views: 1916

Answers (2)

nothingness
nothingness

Reputation: 694

Got it working while inside my firebase child directory, found the firebase function:

            long maxNum = snapshot.getChildrenCount();
            int nums = (int)maxNum;
            disp_msg.setText(msg.toString() + Integer.toString(nums));

Upvotes: 3

stevebot
stevebot

Reputation: 24005

IT should be:

int maxValueInMap=(Collections.max(newPost.values()));

You accidentally did .toString. A String is not a Collection, and therefore .max will not work on it.

I might recommend however, seeing if you can do an order by with limit clause, as it could get expensive to run Collections.max again and again. I can't see a TOP function in the firebase docs, but this would be even better.

Upvotes: 0

Related Questions