Two weeks ago, the Java SE 7 Developer Preview was released. This release is feature-complete, stable, and ready for testing. As Mark Reinhold noted, the Java 7 team is seeking input from the Java community regarding the Developer Preview release.

While the release has been well-exercised by the development team, exposing it to the much broader world of global Java apps is sure to point out some flaws, unanticipated idiosyncracies, or development oversights. Finding these, so they can be dealt with as appropriate long before the formal release of Java 7 (probably in July), is a high priority. Mark puts it this way:

If you’ve been watching JDK 7 development from the sidelines then now is a great time to download a build and take it for a spin. See if your favorite project still compiles and runs, see if it runs any faster than before, or try out one of the manynew features.

Let us know what you think The sooner, the better. We’ll do our best to read, evaluate, and act on all feedback received in the forums or via the usual bug-reporting channelbetween now and the end of March. After that we’ll gradually ramp down the rate of change in order to stabilize the code, so bugs reported later on might not get fixed in time for the initial release.

There are really two aspects to helping out with testing Java 7. The first, which Mark alludes to above, is seeing how existing apps perform under Java 7. That is, is Java 7 backward-compatible in all the expected ways? And, does it deliver performance improvements for existing apps?

In addition, there are the new Java 7 features. These have been talked about a lot. Our current poll, in fact, is about some of the key Java 7 enhancements. In the poll, you select which enhancement is most important for your work. By downloading the Developer Preview, you can get a jump start on trying out some of those new features, and really see how they're going to work out for you. Updated documentation is available.

The fact is: not that many bugs have been filed against the Developer Preview Release thus far. It would be especially beneficial for all of us to ensure that any backward-compatibility related problems are detected now, rather than later.

Another point: what if something new creates an unanticipated performance bottleneck for apps that significantly exercise certain functions within the Java 7 API? Surely it will be very good to discover this now, while there's still time for adjustments to be made to the code.

Anyway, if you'd like to help ensure that Java 7 will be the best it can possibly be when the final edition is released a few months from now, download the Java SE 7 Developer Preview Release and give it a workout over the next week or two -- and don't forget to provide the development team with feedback, via theJava SE Snapshots Forum or the bug reports channel. Weblogs

Since my last blog post, Shing Wai Chan, Alex Potochkin, and John Ferguson Smart have published new blogs.

Shing Wai-Chan posted keepstate, keepSessions, keep-state, save-sessions-enabled in GlassFish 3.1:

GlassFish supports the preseving of HTTP session data across the redeployment of web application. Prior to GlassFish 3.1, one can achieve this through the command line as follows: asadmin redeploy --properties keepSessions=true --name ${APP_NAME} ${A_WAR} In GlassFish 3.1, web sessions, Stateful Session EJB instances and persistently created EJB timers can be retained between...

Alex Potchkin posted Swing in a better world:

I truly love the Swing GUI toolkit, I enjoy its flexibility, opennes and great abilities. I know that some people say that Swing is too difficult to learn, and I partly accept it because it took me several years working in the Swing team to get the whole picture of the AWT, Java 2D and the Swing itself. The Swing history counts more then 10 years and it is definitely not about end. The new...

and Swing in a better world: java interfaces:

We have all read the "Effective Java" book and know that we should prefer interfaces over abstract classes. This is a known and respected pattern which should be used wherever possible. However the years in the JDK team tauhgt me not to blindly trust to good practices from the world of application programming. A distinctive feature of the JDK is backward compatibility. All programms...

And John Ferguson Smart published Build Pipelines with Jenkins/Hudson:

This article is an extract from the upcoming book Jenkins: The Definitive Guide, to be published in the coming months with O'Reilly.. One of the more interesting plugins to emerge over the last few months is the Build Pipeline plugin, written by the folks at Centrum Systems. The Build Pipelines plugin takes the idea of build promotion further, and helps you design and monitor deployment...

Java News

Here are the news stories we're currently featuring in our Java news section.

Alexis Moussine-Pouchkine discusses GlassFish 3.1 : auto-upgrade or not to auto-upgrade?

If you have a GlassFish 3.0.1 installation you probably have been notified that you can update this installation to the newly released GlassFish 3.1 using the update center. This will do an In-Place Upgrade with the new bits (some 75MB pulled off of the stable.glassfish.orgrepository for the open source edition for instance)...

Geertjan Wielenga asks if it's possible to Never Restart An App During Development?

The dream is... deploy your app once during development, and only once, then keep it running. Don't close it down, ever. Whenever you make a change, anywhere in the app, just redeploy the module where you made the change and the module is reloaded, with the feature being changed while the app state is maintained...

Adam Bien provides another example of Swing Looks ...Great! - New Theme for Synthetica:

The BlackEye look and feel was already introduced. Synthetica comes with a new theme called "Classy"...

The Java Posse #343 - Newscast for Mar 10th 2011 podcast has been published:

* Dick -> Keynote at DevNexus on 21-22nd o; * Tor -> Eclipsecon o; * Java 7 developer builds are now available for download and testing. o ...


Our latest Spotlight is Java Spotlight Episode 20 - Pete St Pierre on SunSPOTs Rev 8:

Interview with Pete St Pierre, Member of Technical Staff working on the Sun SPOT program under Oracle Labs, on the new SunSPOT Rev 8 release that is now available at the Oracle Store. Joining us this week is Alexis Moussine-Pouchkine, Java EE Developer Advocate...

We're also still featuring Markus Eisele's article, High Performance JPA with GlassFish and Coherence - Part 3:

In this third part of my four part series I'll explain strategy number two of using Coherence with EclipseLink and GlassFish. This is all about using Coherence as Second Level Cache (L2) with EclipseLink. General approach. This approach applies Coherence data grid to JPA applications that rely on database hosted data...


Our current poll asks What's the most important Java 7 enhancement for the work you do? Voting will be open until Monday.

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-- Kevin Farnham
Twitter: @kevin_farnham