public Cache
getCache(int dclass) {
	Cache c = (Cache) caches.get(dclass);
	if (c == null) {
		c = new Cache(dclass);
		caches.put(dclass, c);
	}
	return c;
}
@author Brian Wellington &lt;bwelling@xbill.org&gt;
src/main/java/core/org/xbill/DNS/jnamed.java