public int read ( byte b [ ] , int off , int len ) throws IOException { if ( off + len > b . length ) { len = b . length - off ; } if ( len < 0 ) { return - 1 ; } if ( len == 0 ) { return 0 ; } int n = blob . read ( b , off , pos , len ) ; if ( n > 0 ) { pos += n ; return n ; } return - 1 ; }
Read slice of byte array from blob .