question: public void writeBatch ( ) throws IOException { if ( getRetrieval ( ) == INCREMENTAL ) throw new IOException ( "Batch and incremental saving cannot be mixed." ) ; if ( getInstances ( ) == null ) throw new IOException ( "No instances to save" ) ; setRetrieval ( BATCH ) ; if ( m_objectstream == null ) throw new IOException ( "No output for serialization." ) ; setWriteMode ( WRITE ) ; m_objectstream . writeObject ( getInstances ( ) ) ; m_objectstream . flush ( ) ; m_objectstream . close ( ) ; setWriteMode ( WAIT ) ; resetWriter ( ) ; setWriteMode ( CANCEL ) ; }
target:  Writes a Batch of instances.