com.jivesoftware.forum.database.DbForum.setName(String name)：
public void setName(String name) throws ForumAlreadyExistsException {

if (this.name.equals(name)) {
return;
}

try {
if (!this.name.toLowerCase().equals(name.toLowerCase()))
{
Forum forum = factory.getForum(name);
throw new ForumAlreadyExistsException();
}
}catch (ForumNotFoundException e) { }

factory.cacheManager.forumCache.remove(id);

this.name = name;
saveToDb();

factory.cacheManager.forumCache.remove(id);
}
代码中 Forum forum = factory.getForum(name);
factory.cacheManager.forumCache.remove(id);
这两个地方用意是什么？（我的问题可能幼稚，确实看了很久没理清。）