Change Update Center URL

http://wiki.netbeans.org/DevFaqHowToChangeUpdateCenterURL

List updateUnitProviders = UpdateUnitProviderFactory.getDefault().getUpdateUnitProviders(true);
               for (int i = 0; i < updateUnitProviders.size(); i++) {
                   UpdateUnitProvider pr = updateUnitProviders.get(i);
                   String name = pr.getDisplayName();
                   if("MyUpdateCenter".equals(name)){
                           pr.setProviderURL(new URL("http://example.com/updateCenter"));
                           pr.refresh(ProgressHandle.createHandle("UpdateCenter refresh"), true);
                           break;
                   }
               }