Package org.apache.commons.collections

Interface Summary
Bag	Defines a collection that counts the number of times an object appears in the collection.
BidiMap	Defines a map that allows bidirectional lookup between key and values.
BoundedCollection	Defines a collection that is bounded in size.
BoundedMap	Defines a map that is bounded in size.
Buffer	Defines a collection that allows objects to be removed in some well-defined order.
Closure	Defines a functor interface implemented by classes that do something.
Factory	Defines a functor interface implemented by classes that create objects.
IterableMap	Defines a map that can be iterated directly without needing to create an entry set.
KeyValue	Defines a simple key value pair.
MapIterator	Defines an iterator that operates over a Map.
MultiMap	Defines a map that holds a collection of values against each key.
OrderedBidiMap	Defines a map that allows bidirectional lookup between key and values and retains and provides access to an ordering.
OrderedIterator	Defines an iterator that operates over an ordered collection.
OrderedMap	Defines a map that maintains order and allows both forward and backward iteration through that order.
OrderedMapIterator	Defines an iterator that operates over an ordered Map.
Predicate	Defines a functor interface implemented by classes that perform a predicate test on an object.
PriorityQueue	Defines a collection for priority queues, which can insert, peek and pop.
ResettableIterator	Defines an iterator that can be reset back to an initial state.
ResettableListIterator	Defines a list iterator that can be reset back to an initial state.
SortedBag	Defines a type of Bag that maintains a sorted order among its unique representative members.
SortedBidiMap	Defines a map that allows bidirectional lookup between key and values and retains both keys and values in sorted order.
Transformer	Defines a functor interface implemented by classes that transform one object into another.
Unmodifiable	Marker interface for collections, maps and iterators that are unmodifiable.

Class Summary
ArrayStack	An implementation of the java.util.Stack API that is based on an ArrayList instead of a Vector, so it is not synchronized to protect against multi-threaded access.
BagUtils	Provides utility methods and decorators for Bag and SortedBag instances.
BeanMap	An implementation of Map for JavaBeans which uses introspection to get and put properties in the bean.
BeanMap.MyMapEntry	Map entry used by BeanMap.
BinaryHeap	Binary heap implementation of PriorityQueue.
BoundedFifoBuffer	The BoundedFifoBuffer is a very efficient implementation of Buffer that does not alter the size of the buffer at runtime.
BufferOverflowException	The BufferOverflowException is used when the buffer's capacity has been exceeded.
BufferUnderflowException	The BufferUnderflowException is used when the buffer is already empty.
BufferUtils	Provides utility methods and decorators for Buffer instances.
ClosureUtils	ClosureUtils provides reference implementations and utilities for the Closure functor interface.
CollectionUtils	Provides utility methods and decorators for Collection instances.
ComparatorUtils	Provides convenient static utility methods for Comparator objects.
CursorableLinkedList	A doubly-linked list implementation of the List interface, supporting a ListIterator that allows concurrent modifications to the underlying list.
CursorableLinkedList.Cursor
DefaultMapBag	A skeletal implementation of the Bag interface to minimize the effort required for target implementations.
DefaultMapEntry	A default implementation of java.util.Map.Entry
DoubleOrderedMap	Red-Black tree-based implementation of Map.
EnumerationUtils	Provides utility methods for Enumeration instances.
ExtendedProperties	This class extends normal Java properties by adding the possibility to use the same key many times concatenating the value strings instead of overwriting them.
FactoryUtils	FactoryUtils provides reference implementations and utilities for the Factory functor interface.
FastArrayList	A customized implementation of java.util.ArrayList designed to operate in a multithreaded environment where the large majority of method calls are read-only, instead of structural changes.
FastHashMap	A customized implementation of java.util.HashMap designed to operate in a multithreaded environment where the large majority of method calls are read-only, instead of structural changes.
FastTreeMap	A customized implementation of java.util.TreeMap designed to operate in a multithreaded environment where the large majority of method calls are read-only, instead of structural changes.
FunctorException	Runtime exception thrown from functors.
HashBag	A Bag that is backed by a HashMap.
IteratorUtils	Provides static utility methods and decorators for Iterator instances.
ListUtils	Provides utility methods and decorators for List instances.
LRUMap	An implementation of a Map which has a maximum size and uses a Least Recently Used algorithm to remove items from the Map when the maximum size is reached and new items are added.
MapUtils	Provides utility methods and decorators for Map and SortedMap instances.
MultiHashMap	MultiHashMap is the default implementation of the MultiMap interface.
PredicateUtils	PredicateUtils provides reference implementations and utilities for the Predicate functor interface.
ProxyMap	This Map wraps another Map implementation, using the wrapped instance for its default implementation.
ReferenceMap	Hash-based Map implementation that allows mappings to be removed by the garbage collector.
SequencedHashMap	A map of objects whose mapping entries are sequenced based on the order in which they were added.
SetUtils	Provides utility methods and decorators for Set and SortedSet instances.
StaticBucketMap	A StaticBucketMap is an efficient, thread-safe implementation of java.util.Map that performs well in in a highly thread-contentious environment.
SynchronizedPriorityQueue	A thread safe version of the PriorityQueue.
TransformerUtils	TransformerUtils provides reference implementations and utilities for the Transformer functor interface.
TreeBag	A Bag that is backed by a TreeMap.
UnboundedFifoBuffer	UnboundedFifoBuffer is a very efficient buffer implementation.