ie2 = e2.next();
while (true) {
assert (ie1.urlhash().length == keylength) : "ie1.urlHash() = " + ASCII.String(ie1.urlhash());
assert (ie2.urlhash().length == keylength) : "ie2.urlHash() = " + ASCII.String(ie2.urlhash());
c = ordering.compare(ie1.urlhash(), ie2.urlhash());
//System.out.println("** '" + ie1.getUrlHash() + "'.compareTo('" + ie2.getUrlHash() + "')="+c);
if (c < 0) {
if (e1.hasNext()) ie1 = e1.next(); else break;
} else if (c > 0) {
if (e2.hasNext()) ie2 = e2.next(); else break;