title: How to create own custom data source factory in exoplayer2.x?
body: <p>I have encrypted media file which is to be decrypted before playing. In exoplayer 1.x I implemented my own custom datasource class which extends UriDatasource in which file was decrypted but in exoplayer 2.x there is no such class, all Datasource classes are final that can not be implemented in my datasourcefile.</p>
  
  <p>How to write own custom File Data source factory making use of our custom filedatasource ?</p>
  
  <p>Please help me in this.</p>
  
  <p>Thanks.</p>