Error in Querying

I’ve written following code. Problem is when run this, error on the BackendlessCollection<ChapterMaster> line. please help
BackendlessDataQuery query = new BackendlessDataQuery();
query.setWhereClause(“status = ‘Active’”);
try {
int cItems = 0;
BackendlessCollection<ChapterMaster> coll = Backendless.Data.of(
ChapterMaster.class).find(query);

Are you running this code on Android? If yes, use async method:

Backendless.Data.of(ChapterMaster.class).find(query, new AsyncCallback&lt;BackendlessCollection&lt;ChapterMaster&gt;>() { ... })