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<h2 align="center">&nbsp;</h2>
<h2 align="center">Java Web Start enhancements in version 6</h2>
<h2 align="center"><br /></h2>
<ul>
<li>
<p>JNLP Specification addition of the &lt;update&gt; element with
its &quot;policy&quot; and &quot;check&quot; attributes.</p>
</li>
</ul>
<p style="margin-left: 0.42in">The new &lt;update&gt; element with
its &quot;policy&quot; and &quot;check&quot; attributes is now
supported. The update element describes the applications
preferences on how Java Web Start should check for updates on the
web, and what to do when it is known before launching that an
update is available.<br />
In the previous versions of Java Web Start, the
&lt;offline-allowed&gt; element was overloaded to mean two
things.&nbsp; First, it meant that the application was allowed to
run in &quot;offline&quot; mode. (An application can be run in
offline mode either from the command line by adding the
&quot;-offline&quot; argument, or from the Cache Viewer.)&nbsp;
Second, it meant that attempts to check for update before launching
an application (when not run in offline mode) could time out.&nbsp;
When a check for update times out, the application would be
launched from the cache while the update check continued in the
background.<br />
With the advent of the &lt;update&gt; element and its check
attribute in 6.0, the &lt;offline-allowed&gt; element no longer has
this second meaning.&nbsp; The default values:&nbsp; &lt;update
check=&quot;timeout&quot;/&gt;.&nbsp; which is the same behavior as
previous versions where &lt;offline-allowed&gt; was
specified.&nbsp; For the behavior that previously used whenever
&lt;offline-allowed&gt; was omitted, you need to specify &lt;update
check=&quot;always&quot;/&gt;. A third value &lt;update
check=&quot;background&quot;/&gt; can be specified to always
immediately launch from the cache while spawning a check for update
in the background.&nbsp;&nbsp;&nbsp; The second attribute,
&quot;policy&quot;, is used to determine what to do when it is
known before starting the application that there is an update
available.&nbsp; You can either always get the update, or prompt
the user. The policy attribute values can be either
&quot;always&quot; (this is default) , &quot;prompt-update&quot; or
&quot;prompt-run&quot;.</p>
<ul>
<li>
<p>JNLP Specification relaxation of requirements for the
DownloadService API.</p>
</li>
</ul>
<p style="margin-left: 0.42in">In the previous versions, the URLs
passed as arguments to all of the APIs were restricted to be URLs
to resources listed in the jnlp file(s) of the running
application.&nbsp; This restriction is changed such that there are
no restrictions for signed and trusted code, and the restriction on
untrusted code is not that it be listed in the jnlp file(s), but
only that it be from the same codebase.<br />
Further, URLs to jnlp file(s) themselves are allowed, so that
calling DownloadService.removeResource() can now be used to remove
a whole application from the cache, and
DownloadService.loadResource() can be used to import an
application.<br />
One effect of this change is that resources not listed in any jnlp
file can now be used in an application.&nbsp; For example, after
determining the locale is set to en_xx, an application can then
load resources_en_xx.jar using the DownloadService, without listing
all the available resource jars in the jnlp file. (Allowing you to
dynamically add support for more locales without changing the jnlp
file).</p>
<ul>
<li>
<p>Implementation of a SocketService</p>
</li>
</ul>
<p style="margin-left: 0.42in; margin-bottom: 0in">Another
significant specification change is a clarification in the
definition of the sandbox, that it is only the default sandbox, and
that the implementation is free to prompt the user to allow actions
that wouldn't be allowed by the sandbox.&nbsp; You already saw in
1.5.0 that this was done for printing, so that just by using the
normal printing api in awt, you could expand the sandbox to allow
the application to access the printer (if the user agreed). In 6.0
this is also done for socket connections, so that if an untrusted
application attempts to connect to a url, the user can be prompted
to allow the connection.</p>
<ul>
<li>
<p>New &lt;java&gt; element in jnlp file to replace &lt;j2se&gt;
element.</p>
</li>
</ul>
<p style="margin-left: 0.42in">For jnlp files that will be used
only with Java Web Start version 6.0 or later, the &lt;java&gt;
element can be used to replace the &lt;j2se&gt; tag.&nbsp; (This is
mainly because the Java Platform Standard Edition is no longer
called j2se.)&nbsp; For backward compatibility, the &lt;j2se&gt;
tag will continue to work.&nbsp; The &lt;java&gt; element will be
identical to the &lt;j2se&gt; element..</p>
<ul>
<li>
<p>The &lt;association&gt; element now may contain the &lt;icon&gt;
and &lt;description&gt; sub-elements.</p>
</li>
</ul>
<p style="margin-left: 0.42in">When creating file extension and
mime type associations with your Java Web Start application, you
can now specify a separate icon to be used for each association (as
opposed to using the default icon for the application).&nbsp; Now,
you can also specify a description.</p>
<ul>
<li>
<p>Jar Indexing is fully supported now, and the JNLPClassLoader is
now an instance of the URLClassLoader.</p>
</li>
</ul>
<p style="margin-left: 0.42in">The JNLPClassLoader was rewritten to
extend URLClassLoader.&nbsp; This gives several powerful
advantages.&nbsp;<br />
First, Jar Indexing is now fully supported.&nbsp; If you have
several jar files, and create a jar index in the main jar file that
indexes all the jar files, you can then mark each additional jar as
lazy, and it will not be downloaded until and unless a resource or
class in it is referenced.&nbsp; This makes the old part and
package elements unnecessary for insuring that lazy jars are not
downloaded prematurely.<br />
Second, since the JNLPClassLoader now extends URLClassLoader, an
Application can call getURLs() to get a list of the jar elements
that are listed in the jnlp files (or have been downloaded using
the DownloadService API, even if not listed in any jnlp file, see
above).<br />
Finally, the URL returned for calls to ClassLoader.getResource() is
now the proper JAR URL of the item on the net.&nbsp; In previous
versions, this URL returned was a jar url of the file url item in
the cache.&nbsp; By extending URLClassLoader, the cached location
(if it exists) is meaningless, and it allows Java Web Start to
operate without caching.</p>
<ul>
<li>
<p>Enhanced icon support.</p>
</li>
</ul>
<p style="margin-left: 0.42in">Java Web Start now supports two new
icon formats, &quot;.png&quot;, and &quot;.ico&quot;.&nbsp; This
allows you to specify an icon that will not need to be translated
into a different format depending on its use.&nbsp; You can also
now specify kind=&quot;shortcut&quot;, and Java Web Start will now
honor the width and height hints. This means if you specify:<br />
&lt;icon kind=&quot;shortcut&quot;
href=&quot;menushortcut.ico&quot; width=&quot;16&quot;
height=&quot;16&quot;/&gt;<br />
&lt;icon kind=&quot;shortcut&quot;
href=&quot;desktopshortcut.ico&quot; width=&quot;32&quot;
height=&quot;32&quot;/&gt;<br />
you can specify separate images for any desktop and menu shortcuts
that are created.&nbsp; (note: for desktop shortcuts, Java Web
Start will use the icon whose size is closer to 32X32, and for menu
shortcuts Java Web Start will use the icon whose size is closer to
16X16 )</p>
<ul>
<li>
<p>Enhanced support for Add/Remove program entries on Windows.</p>
</li>
</ul>
<p style="margin-left: 0.42in">The Windows Add/Remove program
entries for Java Web Start applications will now include the
publisher, publisher web site, install date, and application icon
from the information block of the jnlp file.</p>
<ul>
<li>
<p>Desktop shortcut tooltips.</p>
</li>
</ul>
<p style="margin-left: 0.42in">Desktop shortcuts created by Java
Web Start will now use the &lt;description&gt; element in the jnlp
file to create a toolkit describing the application.</p>
<ul>
<li>
<p>JNLPDownloadServlet enhancements.</p>
</li>
</ul>
<p style="margin-left: 0.42in">The JnlpDownloadServlet now contains
both a $$hostname and a $$site macro. The $$hostname macro is
expanded to contain the host name. The $$site macro is expanded to
contain the web site address without the WAR context portion.</p>
<ul>
<li>
<p>The list of safe vm args and safe properties has been
expanded.</p>
</li>
</ul>
<p style="margin-left: 0.42in">See the developers guide for the
current list of safe properties and vm args.</p>
<ul>
<li>
<p>Several Command Line Interface (CLI) items have been changed or
added. See the developers guide for the current Javaws CLI.</p>
</li>
</ul>
<h3 align="center">Enhancements Common to Java Web Start and Java
Plug-in</h3>
<ul>
<li>
<p>All dialogs have been redesigned to be more user friendly.</p>
</li>
</ul>
<p style="margin-left: 0.42in">All of the dialogs and screens shown
by Java Web Start and Java Plug-in have been redesigned with help
from the User Experience team to be more user friendly, intuitive,
and accessible.</p>
<ul>
<li>
<p>DownloadEngine and cache consolidation and redesign.</p>
</li>
</ul>
<p style="margin-left: 0.42in">The entire caching mechanism and
download engine has been redesigned and consolidated between Java
Web Start and Java Plug-in.&nbsp;<br />
This brings several new features to Java Web Start, previously
available only in Java Plug-in and vice versa.</p>
<ul>
<li>
<p style="margin-bottom: 0in">Caching can be disabled now entirely
via the Java Control Panel.<br /></p>
</li>
<li>The cache max size set in the JCP is now honored in Java Web
Start, and a cleanup thread may be started by Java Web Start to
removed LRU items from the cache when it is approaching the max
size set by the user.</li>
</ul>
<ul>
<li>The &quot;cache-control: no-cache&quot; HTTP header is now
supported. &quot;no-cache&quot; means cached contents cannot be
used without re-validation. When the no-cache directive is used ,
an update check is always made to make sure the cached content is
the same as the server copy pointed to, by the resource URL. If so,
cached copy can be used. If not, server copy will be downloaded.
Expiration field is ignored, which means that even if the cached
resource is not expired yet, update check will still be
performed.</li>
</ul>
<ul>
<li>The expiration-date will be honored.&nbsp; If a downloaded
resource contains an expiration date, it will not be used after
that date.</li>
</ul>
<p style="margin-left: 0.42in">Note: The format of the cache is
completely changed and should never be assumed.&nbsp; Any existing
code that assumed the previous format of the cache, for either Java
Web Start or Java Plug-in will no longer work.&nbsp; Existing
applications in the Java Web Start cache will be upgraded and
converted to the new cache format the first time you run a Java Web
Start application, or if you launch the cache viewer using
&quot;javaws -viewer&quot;. Likewise, the system cache will be
upgraded and converted to the new format the first time you launch
Java Web Start in system mode, or if you just launch &quot;javaws
-system&quot;.</p>
<ul>
<li>
<p>The Java Console is now excluded from modality.</p>
</li>
</ul>
<p style="margin-left: 0.42in">By using the new modality features
added by AWT in Java 6, you can interact with the Java Console even
when the Application displays a modal Dialog.</p>
<ul>
<li>
<p>New support for OCSP/CRL</p>
</li>
</ul>
<p style="margin-left: 0.42in">Java Web Start and Java Java Plug-in
support CRL (Certificate Revocation Lists) and OCSP (Online
Certificate Status Protocol) for verifying the certificates.</p>
<ul>
<li>
<p>New Support for SSL/TSL</p>
</li>
</ul>
<p style="margin-left: 0.42in">An Option has been added to the Java
Control Panel to select the default SSL handshaking protocol.<br />
The default is set to SSLv3 and SSLv2, but then user or enterprise
can change it to TSL.<br />
<br />
<br />
<br /></p>
<p style="margin-bottom: 0in"><br /></p>
<p style="margin-left: 0.42in; margin-bottom: 0in"><br /></p>

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