+ @Override
+ public List<?> getItemIds(int startIndex, int numberOfItems) {
+ synchronized (this.groups) {
+ int endIndex = startIndex + numberOfItems;
+ if (endIndex > this.groups.size()) {
+ endIndex = this.groups.size() - 1;
+ }
+ return this.groups.subList(startIndex, endIndex);
+ }
+ }
+