commons-collections/STATUS.html

194 lines
8.7 KiB
HTML

<html>
<head>
<title>Status File for Jakarta Commons "Collections" Package</title>
<head>
<body bgcolor="white">
<div align="center">
<h1>The Jakarta Commons <em>Collections</em> Package</h1>
$Id: STATUS.html,v 1.13 2002/03/15 05:41:23 morgand Exp $<br>
<a href="#Introduction">[Introduction]</a>
<a href="#Dependencies">[Dependencies]</a>
<a href="#Release Info">[Release Info]</a>
<a href="#Committers">[Committers]</a>
<a href="#Action Items">[Action Items]</a>
<br><br>
</div>
<a name="Introduction"></a>
<h3>1. INTRODUCTION</h3>
<p>The <em>Collections</em> package contains a set of Java classes that
extend or augment the Java Collections Framework.
The following classes are included:</p>
<ul>
<li><strong>ArrayEnumeration</strong> - a java.util.Enumeration wrapper for arrays.</li>
<li><strong>ArrayIterator</strong> - a java.util.Iterator wrapper for arrays.</li>
<li><strong>ArrayStack</strong> - 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.</li>
<li><strong>Bag</strong> - A Collection that keeps a count of its members of the same
type, using <code>hashCode</code> to check for equality. Suppose
you have a Bag that contains <code>{a, a, b, c}</code>. Calling
getCount on <code>a</code> would return 2, while calling
uniqueSet would return <code>{a, b, c}</code>. <i>Note: this is an
interface with several implementations.</i></li>
<li><strong>BeanMap</strong> - An implementation of the java.util.Map API
that is based on a JavaBean using introspection. The property names are the
keys of the map and the property values are the values of the map.</li>
<li><strong>CollectionUtils</strong> - a variety of helper methods
for working with collections.</li>
<li><strong>ComparableComparator</strong> - A Comparator that compares Comparable objects.
This Comparator is useful, for example,
for enforcing the natural order in custom implementations
of SortedSet and SortedMap.</li>
<li><strong>ComparatorChain</strong> - ComparatorChain is a Comparator that wraps one or
more Comparators in sequence. The ComparatorChain
calls each Comparator in sequence until either 1)
any single Comparator returns a non-zero result
(and that result is then returned),
or 2) the ComparatorChain is exhausted (and zero is
returned). This type of sorting is very similar
to multi-column sorting in SQL, and this class
allows Java classes to emulate that kind of behaviour
when sorting a List.</li>
<li><strong>CursorableLinkedList</strong> - an implementation of the java.util.List
interface supporting a java.util.ListIterator that allows concurrent
modifications to the underlying list.</li>
<li><strong>DoubleOrderedMap</strong> - Red-Black tree-based implementation of Map.
This class guarantees
that the map will be in both ascending key order and ascending
value order, sorted according to the natural order for the key's
and value's classes.</li>
<li><strong>ExtendedProperties</strong> - extends normal Java properties by adding
the possibility to use the same key many times, concatenating the value strings
instead of overwriting them.</li>
<li><strong>FastArrayList</strong> - a custom 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.</li>
<li><strong>FastHashMap</strong> - a custom 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.</li>
<li><strong>FastTreeMap</strong> - a custom 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.</li>
<li><strong>FilterIterator</strong> - A Proxy <code>Iterator</code> which takes a
<code>Predicate</code>
instance to filter out objects from an underlying <code>Iterator</code> instance.
Only objects for which the
specified <code>Predicate</code> evaluates to <code>true</code> are
returned.</li>
<li><strong>FilterListIterator</strong> - A proxy <code>ListIterator</code> which
takes a <code>Predicate</code> instance to filter
out objects from an underlying <code>ListIterator</code>
instance. Only objects for which the specified
<code>Predicate</code> evaluates to <code>true</code> are
returned by the iterator.</li>
<li><strong>HashBag</strong> - An implementation of <strong>Bag</strong> that is backed by a
HashMap.</li>
<li><strong>ListUtils</strong> - miscelaneous utilities to manipulate Lists.</li>
<li><strong>MultiMap</strong> - This is simply a Map with slightly different semantics.
Instead of returning an Object, it returns a Collection.
So for example, you can put( key, new Integer(1) );
and then a Object get( key ); will return you a Collection
instead of an Integer. This is an interface implemented
by <strong>MultiHashMap</strong>.</li>
<li><strong>PriorityQueue</strong> - a PriorityQueue interface, with
<strong>BinaryHeap</strong> and <strong>SynchronizedPriorityQueue</strong>
implementations.</li>
<li><strong>ProxyMap</strong> - This <code>Map</code> wraps another <code>Map</code>
implementation, using the wrapped instance for its default
implementation. This class is used as a framework on which to
build to extensions for its wrapped <code>Map</code> object which
would be unavailable or inconvenient via sub-classing (but usable
via composition).</li>
<li><strong>ReverseComparator</strong> - Reverses the order of another comparator.</li>
<li><strong>SequencedHashMap</strong> - A map of objects whose mapping entries are
sequenced based on the order in
which they were added.</li>
<li><strong>SingletonIterator</strong> - An Iterator over a single
object instance.</li>
<li><strong>SortedBag</strong> - A type of <strong>Bag</strong> that maintains order among its unique
representative members</li>
<li><strong>TreeBag</strong> - An implementation of <strong>Bag</strong> that is backed by a
TreeMap. Order will be maintained among the unique representative
members.</li>
</ul>
<a name="Dependencies"></a>
<h3>2. DEPENDENCIES</h3>
<p>The <em>Collections</em> package is dependent upon the following external
components for development and use:</p>
<ul>
<li><a href="http://java.sun.com/j2se">Java Development Kit</a>
(Version 1.2 or later)</li>
<li><a href="http://www.junit.org">JUnit Testing Framework</a>
(Version 3.7 or later) - for unit tests only, not required
for deployment</li>
</ul>
<a name="Release Info"></a>
<h3>3. RELEASE INFO</h3>
<p>Current Release:
<a href="http://jakarta.apache.org/builds/jakarta-commons/release/commons-collections/v1.0">Version 1.0</a>
<p>Planned Next Release: TBD</p>
<a name="Committers"></a>
<h3>4. COMMITTERS</h3>
<p>The following individuals are the primary developers and maintainers of this
component. Developers who plan to use <em>Collections</em> in their own
projects are encouraged to collaborate on the future development of this
component to ensure that it continues to meet a variety of needs.</p>
<ul>
<li><a href="mailto:mas@apache.org">Michael A. Smith</a></li>
<li><a href="mailto:morgand@apache.org">Morgan Delagrange</a></li>
<li><a href="mailto:donaldp@apache.org">Peter Donald</a></li>
<li><a href="mailto:geirm@apache.org">Geir Magnusson Jr.</a></li>
<li><a href="mailto:craigmcc@apache.org">Craig McClanahan</a></li>
<li><a href="mailto:jstrachan@apache.org">James Strachan</a></li>
<li><a href="mailto:rwaldhoff@apache.org">Rodney Waldhoff</a></li>
<li><a href="mailto:jvanzyl@apache.org">Jason van Zyl</a></li>
<li><a href="mailto:bayard@apache.org">Henri Yandell</a></li>
</ul>
<a name="Action Items"></a>
<h3>5. ACTION ITEMS</h3>
<p>Want to help? Here's some "to do" items the team has identified.</p>
<table border="1">
<tr>
<th width="80%">Action Item</th>
<th width="20%">Volunteer</th>
</tr>
<tr>
<td><strong>Additional Contributions</strong>. Other collection
or collection-related classes.</td>
<td align="center">&nbsp;</td>
</tr>
<tr>
<td><strong>Generalized Unit Tests</strong>. Create a generic
set of Unit Tests that test the standard contracts of the basic
Java Collections interfaces (List, Set, Map, etc.)</td>
<td align="center">&nbsp;</td>
</tr>
<tr>
<td><strong>Additional Documentation</strong>. Create simple
User's Guide, examples, or other documentation for this package.</td>
<td align="center">&nbsp;</td>
</tr>
</table>
</body>
</html>