private static void writeDuplicates() { Main.status("Writing duplicates."); if (!dup_post_list.isEmpty()) { Main.status(String.format("%s\t%s", "older_post", "newer_post")); for (Post post : dup_post_list.keySet()) { Main.status(String.format("%s\t%s", post.post_id, dup_post_list.get(post).post_id)); } } else { Main.status("There are no duplicates."); } Main.status("Writing duplicates done."); }