commons-collections/RELEASE-NOTES.html

<title>RELEASE NOTES: COLLECTIONS 3.0</title>

<center><h2>RELEASE NOTES: COLLECTIONS 3.0</h2></center>

<p><i>Collections 3.0</i> includes a significant number of new collections
in addition to various bug fixes and refactoring changes. The major additions
are:
</p>
<ul>
<li><strong>Buffers</strong> - A new collection interface for queues and 
queue-like things.</li>
<li><strong>Decorators</strong> - A group of static utility classes that provide
decorators for other collections</li>
</ul>
<p>
The decorators are found on classes named <code>XxxUtils</code> where Xxx is the
collection type. The decorators are:
</p>
<ul>
<li><strong>Synchronized</strong> - Synchronized decorators where not provided 
by <code>Collections</code>.</li>
<li><strong>Unmodifiable</strong> - Unmodifiable decorators where not provided 
by <code>Collections</code>.</li>
<li><strong>Predicated</strong> - Decorators that only allow the addition of an
element to the collection if it matches a <code>Predicate</code>.</li>
<li><strong>FixedSize</strong> - Decorators that ensure that the list/map 
cannot change size.</li>
<li><strong>Lazy</strong> - Decorators that create objects on demand using a
<code>Factory</code>.</li>
</ul>
<p>
Access to Iterators and Comparators has also been brought in line, by the provision
of <code>IteratorUtils</code> and <code>ComparatorUtils</code>.
</p>

<hr />

<center><h3>
NEW COLLECTIONS, COMPARATORS, ITERATORS AND UTILITY CLASSES
</h3></center>

<p>These collections are new to <i>Collections 3.0</i>:</p>

<ul>
</ul>

<p>These comparators are new to <i>Collections 2.1</i>:</p>

<ul>
</ul>

<p>These iterators are new to <i>Collections 2.1</i>:</p>

<ul>
<li><strong>ArrayListIterator</strong> - Provides a ListIterator over an array
    of any type (including primitive arrays).</li>

<li><strong>LoopingIterator</strong> - Provides an Iterator that loops repeatedly
	over the collection.</li>

<li><strong>ObjectArrayIterator/ListIterator</strong> - 
	Provides iterators over an Object array.</li>

<li><strong>ResetableIterator/ListIterator</strong> - 
	Interface that defines a reset() method to reset the iterator back to the start.</li>
</ul>

<p>These are the new utility classes:</p>

<ul>
</ul>


<hr />

<center><h3>CHANGED CLASSES</h3></center>

<p>These iterators have changed since <i>Collections 2.1</i>:</p>

<ul>
<li><strong>ArrayIterator</strong> - 
	This now implements the ResetableIterator interface. It also supports a start index to iterate from.</li>

<li><strong>CollatingIterator</strong> - 
	The remove() method now throws IllegalStateException not NoSuchElementException.</li>

<li><strong>FilterIterator</strong> - 
	The remove() method is now supported, with some limitations.</li>

<li><strong>IteratorChain</strong> - 
	Bug fix for when remove() called before hasNext()/next().</li>

<li><strong>SingletonIterator/ListIterator</strong> - 
	These now implement the ResetableIterator interface.</li>
</ul>


<hr />


<center><h3>REFACTORING</h3></center>

<p><u>Documentation</u></p>

<p>Every class released in 3.0 has been changed in some way.
This might be simply the update to the Apache license, or it could be improved Javadoc.</p>