title: Check if child exists in firebase
body: <p>Android Java Firebase:</p>
  
  <pre><code> DatabaseReference root = FirebaseDatabase.getInstance().getReference();
      DatabaseReference users = root.child("Users");
  users.addListenerForSingleValueEvent(new ValueEventListener() {
              @Override
              public void onDataChange(DataSnapshot snapshot) {
                  if (snapshot.childExists("name")) {
                      // run some code
                  }
              }
  
              @Override
              public void onCancelled(DatabaseError databaseError) {
  
              }
          });
  </code></pre>
  
  <p>This is my code, but <code>childexists</code> is not a valid working method. What is a way to check? If there is something similar can I just fix it?</p>