question: private int readInputData ( byte [ ] buf , int off , int len ) throws IOException { cbLock . lock ( ) ; try { return iis . read ( buf , off , len ) ; } finally { cbLock . unlock ( ) ; } }
target:  This method is called from native code in order to fill native input buffer. We block any attempt to change the reading state during this method, in order to prevent a corruption of the native decoder state.