public static FastWritable tryGetInstance ( String name , Configuration conf ) { if ( name . length ( ) != NAME_LEN ) { // we use it to fast discard the request without doing map lookup return null ; } FastWritable fw = register . get ( name ) ; return fw == null ? null : fw . getFastWritableInstance ( conf ) ; }
Tries to get an instance given the name of class . If the name is registered as FastWritable the instance is obtained using the registry .