Apache Wicket 6.21.0 发布，现在使用语义版本来开发 Wicket，现已提供在 Maven：
<dependency>
<groupId>org.apache.wicket</groupId>
<artifactId>wicket-core</artifactId>
<version>6.21.0</version>
</dependency>
下载：
* Source: http://www.apache.org/dyn/closer.cgi/wicket/6.21.0
* Binary: http://www.apache.org/dyn/closer.cgi/wicket/6.21.0/binaries
改进列表
=====================
** Bug 修复
* [WICKET-5882] - AutoComplete suggestion list disappear when I
click on autoComplete scrollbar in IE
* [WICKET-5898] - StackOverflowError after form submit with a
validation error
* [WICKET-5925] - wicket-examples DataTablePage is broken
* [WICKET-5927] - Velocity remote code execution
* [WICKET-5939] - AjaxEventBehavior should not lower-case the event name
* [WICKET-5941] - Headers not rendered for components inside
TransparentWebMarkupContainer on ajax update
* [WICKET-5944] - CSRF prevention does not work with https URLs on
the default port
* [WICKET-5946] - JavaScript/Css PackageResource should use the
same charset for compressing
* [WICKET-5959] - HTML input placeholder text breaks
AutoCompleteTextField in IE11
* [WICKET-5960] - Page header isn't rendered for pages where URL
has changed during render
* [WICKET-5968] - CachingResourceLocator lookup key doesn't take
strict into account
* [WICKET-5970] - UrlRenderer does not render fragments
* [WICKET-5973] - IllegalArgumentException 'bytes' cannot be
negative. on opening Inspector
* [WICKET-5978] - LazyInitProxyFactory fills permgen space
* [WICKET-5989] - BaseWicketTester#startComponentInPage fails for
pages with <wicket:header-items></wicket:header> placeholder
* [WICKET-5994] - Mounted TemplateResourceReference throws
org.apache.wicket.WicketRuntimeException when https is used
* [WICKET-5996] - Mounted packages throw IllegalArgumentException
when visiting base package url.
* [WICKET-6005] - WicketRuntimeException from
AjaxPagingNavigator#onAjaxEvent
** 改进
* [WICKET-5926] - Arquillian Support with Container ServletContext
in BaseWicketTester/WicketTester.
* [WICKET-5930] - Upgrade Atmosphere to 2.2.7
* [WICKET-5932] - Allow empty column list for DataTable
* [WICKET-5933] - Avoid serialization of untouched page after ajax request
* [WICKET-5935] - IoC Guice: cache proxies and fail on creation
when binding is missing
* [WICKET-5945] - add a new topic/listener that notifies of Ajax calls done
* [WICKET-5948] - wicket-ajax.js probably doesn't traverse the
children of <div> or <span>
* [WICKET-5955] - error from WebPage # reportMissingHead
* [WICKET-5974] - Change AjaxPagingNavigator#onAjaxEvent() to only
consider parent components that have setOutputMarkupId(true)
* [WICKET-5976] - Improve the documentation of FeedbackMessages
first(int level)
* [WICKET-5986] - NumberTextField<N> should use Models for
minimum, maximum and step
** 任务
* [WICKET-5951] - Upgrade Atmosphere to 2.2.8
Wicket是一个Java 语言的Web开发框架，与Struts，WebWork，Tapestry 相类似。其特点在于对Html和代码进行了有效的分离（有利于程序员和美工的合作），基于规则的配置(减少了XML 等配置文件的使用)，学习曲线较低（开发方式与C/S相似），更加易于调试（错误类型比较少，而且容易定位）。
