CloseableIterator<E> For iterators that need to be closed after use. 
EnclosedIterable<T> A limited collection view that may be backed by the something that needs closing, for example a connection to a database. 
MultiMap<K, V, C extends Collection<V>>  
PagedList<E> Page over an underlying list, either by navigating to a page or iterating a page at a time. 
Sized Something that contains a number of items. 


CloseableIterator.ListResolver<T> Utility class for transforming a EnclosedIterable into a List. 
CollectionBuilder<T> Convenience class for creating collections (Set and List) instances or enclosed iterables
CollectionEnclosedIterable<T> Simple collection based EnclosedIterable
CompositeMap<K, V> Provides a union view of two maps. 
CopyOnWriteSortedCache<T extends Comparable<T>> Simple copy-on-write ordered cache with Set semantics. 
EnclosedIterable.ListResolver<T> Utility class for transforming a EnclosedIterable into a List. 
EnumerationIterator<E> Adaptor for turning an Enumeration into an Iterator. 
FixedSized Statically sized implementation of Sized 
IdentitySet<T> A java.util.Set implementation that considers objects equal if an only if they are the same instance. 
IdentitySet.IdentityReference<T> Stores a reference to any Object. 
IteratorEnumeration<E> Adaptor for turning an Iterator an into Enumeration. 
ListOrderComparator<T> Compare objects based on their order in a supplied list. 
LRUMap<K, V> This class is deprecated. Since v6.2 Use com.atlassian.cache.CacheFactory instead and build a proper cache.  
MapBuilder<K, V> Utility for easily creating Maps of all standard types. 
MemoizingMap<K, V> A Map that is backed by a MemoizingMap.Master map that contains suppliers for the values that are called lazily when required. 
MemoizingMap.Master<K, V> Master that individual Maps can be printed from. 
MemoizingMap.Master.Builder<K, V> Used to build a MemoizingMap.Master that individual local copies can then be copied from. 
MultiMaps Static factory methods for creating and manipulating multi-maps
ResolvingComparator<I, O> Comparator that first resolves an input to an output type, and then delegates to a comparator of the output type. 
Transformed Static factory for creating transformed Map, Set, and Iterator instances.