code: public synchronized void
  addRecord(Record r, int cred, Object o) {
  	Name name = r.getName();
  	int type = r.getRRsetType();
  	if (!Type.isRR(type))
  		return;
  	Element element = findElement(name, type, cred);
  	if (element == null) {
  		CacheRRset crrset = new CacheRRset(r, cred, maxcache);
  		addRRset(crrset, cred);
  	} else if (element.compareCredibility(cred) == 0) {
  		if (element instanceof CacheRRset) {
  			CacheRRset crrset = (CacheRRset) element;
  			crrset.addRR(r);
  		}
  	}
  }
docs: Adds a record to the Cache.
  @param r The record to be added
  @param cred The credibility of the record
  @param o The source of the record (this could be a Message, for example)
  @see Record