/**
* Returns an unmodifiable Collection of all groups in the system.
*
* @return an unmodifiable Collection of all groups.
*/
@SuppressWarnings("unchecked")
public Collection<Group> getGroups() {
Collection<String> groupNames = (Collection<String>) groupMetaCache.get(GROUP_NAMES_KEY);
if (groupNames == null) {
synchronized (GROUP_NAMES_KEY.intern()) {
groupNames = (Collection<String>) groupMetaCache.get(GROUP_NAMES_KEY);
if (groupNames == null) {
groupNames = provider.getGroupNames();
groupMetaCache.put(GROUP_NAMES_KEY, groupNames);
}
}
}
return new GroupCollection(groupNames);
}
/**
* Returns an iterator for all groups that the entity with the specified JID is a member of.
*
* @param user the JID of the entity to get a list of groups for.
* @return all groups that an entity belongs to.
*/
@SuppressWarnings("unchecked")
public Collection<Group> getGroups(JID user) {
String key = user.toBareJID();
Collection<String> groupNames = (Collection<String>) groupMetaCache.get(key);
if (groupNames == null) {
synchronized (key.intern()) {
groupNames = (Collection<String>) groupMetaCache.get(key);
if (groupNames == null) {
groupNames = provider.getGroupNames(user);
groupMetaCache.put(key, groupNames);
}
}
}
return new GroupCollection(groupNames);
}
/**
* Returns all groups given a start index and desired number of results. This is useful to support
* pagination in a GUI where you may only want to display a certain number of results per page. It
* is possible that the number of results returned will be less than that specified by numResults
* if numResults is greater than the number of records left in the system to display.
*
* @param startIndex start index in results.
* @param numResults number of results to return.
* @return an Iterator for all groups in the specified range.
*/
@SuppressWarnings("unchecked")
public Collection<Group> getGroups(int startIndex, int numResults) {
String key = GROUP_NAMES_KEY + startIndex + "," + numResults;
Collection<String> groupNames = (Collection<String>) groupMetaCache.get(key);
if (groupNames == null) {
synchronized (key.intern()) {
groupNames = (Collection<String>) groupMetaCache.get(key);
if (groupNames == null) {
groupNames = provider.getGroupNames(startIndex, numResults);
groupMetaCache.put(key, groupNames);
}
}
}
return new GroupCollection(groupNames);
}