how to reduce redo log size when loading high volumns of data by using java or c language into oracl

 In currently our system,there are several collect machines process data and then load into oracle database by using sqlldr of conventional style.So it always generated a large mount of redo log .So i was wondering if have a best way to effective reduce redo log size in jave or c language like plsql that we can use "forall" combined with "insert/*+ append_values(x)*/ into x values(l_tab(i))" method to reduce redo log.By the way the version of database is 11R2.Thanks.