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Dancing While Gaming – Multitasking VMs on Real Devices

Posted by hiheiss on May 19, 2006 at 08:35 PM | Permalink | Comments (2)

The JavaOne session, “Dancing While Gaming – Multitasking VMs on Real Devices”, focused on helping developers gain a wider and deeper understanding of the Multitasking VM implementation on real devices based on the interaction between Sun and Samsung who are engaged in a joint collaboration through the work of Jae Hyou Lee of Samsung Electronics and Yaniv Shani of Sun.

MVM deployment is based on the Sun JWC1.1.3 (Java Wireless Client 1.1.3) which comes with multi-tasking capabilities. The MVM deploys most of the MSA (Mobile Service Architecture) JSRs. It has been tested with hundreds of games and applications from leading content providers.

So what is MVM? The Multi-Tasking Virtual Machine is a technology that allows the end-user to execute multiple Java applications simultaneously. MVM enables preferred and rich applications like MP3 playing, Instant Messaging and mail clients. Users of MVM want to run multiple Java applications simultaneously and want to be able to switch applications very rapidly. The typical MVM player might be a teenager who loves to listen to MP3 players, chat with friends over the Net, and play video games simultaneously. Multi-tasking capabilities enable all these activities to be conducted on the same device at the same time.

The Isolation Model

To execute multiple applications, the isolation model was introduced in the VM. Each application runs in its own logical Virtual Machine environment, called an isolate. Within the JVM, each isolate is represented as a task. A task consists of one or more Java threads of execution. All tasks execute in the same single OS task context. All tasks share constant data structure and runtime support functions. Each task encapsulates non-sharable program state MVM.

“In the CLCD space, we would like to address limited operating systems that lack native process modeling support,” said Shani. “This is the main reason why in the CLCD space, the VM implementation conducts both the Java task and Java thread scheduling internally within the VM.”

Implementation Details

Each task has a separate, private copy of the static variables of all the loaded Java classes. Static variables are only global to all threads within a particular task. Each task maintains a private copy of ‘count’. The Class representation is shared. Synchronization has to be task private. Threads in one task cannot block threads in another task. Blocking threads across tasks isn’t allowed.

Resource Management

The low-level part of the VM is responsible for all CPU time and memory resources in order to ensure that all tasks get their “fair” share. Other resources, such as network bandwidth and communication ports are managed by the profile layer.

Resource Management – Scheduling

Tasks and threads are scheduled internally by the JVM. Fair scheduling algorithm is used for task scheduling in order to prevent one task from taking disproportionate CPU time and causing other tasks to stop. The ‘isolate’ class offers a set of APIs to modify the priority levels for each task. In most cases MIDlets that execute in the foreground get to have more CPU cycles compared to others that run in the background.

Resource Management – Memory

The VM requires a large consecutive memory block from the underlying OS. Allocations for all tasks are made from this same global heap region. The VM has a bookkeeping mechanism that accounts for each task’s total heap memory consumption. The VM injects OutOfMemoryError as needed to inform tasks that heap space has become scarce.

The Profile Level

The presentation turned to what must be done at the profile level to transform their implementation into one capable of multi-tasking. They have been using Sun’s latest JWC1.1.3, which comes with multi-tasking capabilities. It allows only a single MIDlet to execute in the foreground at a certain time.

A MIDlet application is said to be in the foreground when:

-- Its displayable controls the display.
-- It handles events from the user input mechanism since they are automatically routed to it.

An application is in the background when:

-- Its displayable does not control the display.
-- It does not handle the user input mechanism.
-- Zero or more MIDlets can execute in the Background
at a time.

The application manager is critical for task switching. They use a resident Java MIDlet for the application manager; it is launched in the background when the device ends its boot phase. When users switch it to the foreground, they see a list of all running applications and can switch between them quickly. The app manager also displays background MIDlet alerts, when one wants to drive the user intention.

They next displayed some demos showing how to switch MIDlets to the background and switching between MIDlet states.

Switching a MIDlet to the Background

A short ‘hot’ key press is used for switching between running apps.
Upon a short ‘hot' key press the foreground MIDlet will be
placed in the background and the main device menu will be
displayed on the screen.

Upon a long ‘Hot’ key press the foreground MIDlet will be
placed in the background and the ‘Application manager’ will
be displayed on the screen. The user can see the list of running apps and can switch to another app.

Upon calling setCurrent(null) the MIDlet will be placed in the
background and the ‘idle’ screen of the device will be
displayed. This enables MIDlets to place themselves in the background.

Interrupting the User

A demo of a user experience focused on ways to interrupt the user when a background MIDlet wants to drive the user’s attention.

-- Background MIDlet calls Display.setCurrent(alert)
-- Background MIDlet tries to access a protected API and a security dialog is prompted.
-- Noteworthy event occurred in the background, e.g., Incoming IM while playing a game.


Managing Resources

The session turned to resource management. In a single-tasking environment, the MIDlet has access to all of the available resources. In a multitasking environment, MIDlets have to compete for available resources

Resource management mechanisms include:

Reservation -- A reservation mechanism sets aside a certain amount of a resource for a MIDlet and keeps it available for that MIDlet and that MIDlet alone

Quota -- A quota mechanism permits a MIDlet to allocate up to a
certain amount of a resource. If the MIDlet attempts to allocate more resources than its quota, the attempt fails, even if resources are actually available on the system.

Revocation -- The system can revoke a resource from a MIDlet and give it to another MIDlet. Resource revocation examples include CPU cycles, display access, and audio playback. Resource revocation doesn’t always have a dramatic effect on
the MIDlet’s execution

The session went on to cover LCD display, and sound issues and offered guidelines for resource policy selection. The key points were:

-- Resource policy definition relies on the underlying platform
capabilities and requirements.

-- A fixed partition policy should be used for fundamental resources that are required by the majority of the applications.

-- An open policy should be used for resources that are used by
specific MIDlets and have limited availability (e.g. Bluetooth, Location).

-- The Display and Sound requires special handling.


Multitasking Safety

Regarding safety, the native JVM task can run native code for any task, hence the code must be made aware of the task on whose behalf it is being called and possibly allocating resources. When the task context is established, the code is considered multitasking safe. Sun’s JWC software is multitasking safe.

The session closed with an exploration of such topics as static and global variables, issues of native code execution, MIDlet guidelines, and basic resource awareness principles.

The take-home message from my perspective is that MVM technology fits nicely with what is happening, for better or worse, not only in youth culture in the US and much of the world, but among older generations. We are living speeded up lives and engage in multi-tasking, out of both necessity and pleasure and we want to be able to do it comfortably and quickly from the same device.

“Dancing while gaming” is here to stay and Sun and Samsung are on to something. More power to them.




Let's Make a Deal: Java and .Net Hold Hands Over Web Services

Posted by hiheiss on May 18, 2006 at 08:08 PM | Permalink | Comments (3)

At JavaOne earlier this week, I took in TS-5540, “Making Java/.Net Technology Based Web Services Interoperability Real” with Sun’s Arun Gupta and Microsoft’s Kirill Gavrylyuk. Sun and Microsoft developers have been meeting at “Plugfests” in Microsoft’s test facilities in Redmond, Washington, where they identify bugs and work to assure interoperability in their web services code. Both have strong customer-driven motivations for removing interoperability barriers between their web services stacks. The collegial environment is reported to have been refreshing and productive. Arun Gupta’s blog has interesting comments:

http://weblogs.java.net/blog/arungupta/archive/2005/11/sun_sleepless_i_1.html

So here were two developers from corporations that once viewed each other as enemies offering a joint presentation. Economic necessity makes strange bedfellows.

Gupta enunciated their basic message: “In this talk, we intend to show you that enterprise web services are real,” said Gupta. “We also intend to show you how web services enable enterprise integration scenarios within and across business boundaries.”

Web services are well adopted on both Java and .Net platforms. Recent developments in Microsoft’s Windows Communication Foundation, which is Microsoft’s web services platform, and the open source Glassfish communities’ compatible app server have made interoperability a reality. They are not just talking about a promising future.

Gavrylyuk and Gupta presented a scenario with a Sun-managed retail quote service which gets quotes from a service running in a homogeneous environment. It gets quotes from a variety of client services, some of which run in a .NET Microsoft environment. It also gets information from a GlassFish client. In both cases they use secure and reliable communication.

They began with consumer integration. Suppose consumers rely on the Sun-managed quote service that uses WCF and Glassfish clients. How to achieve data interoperability? The two managed environments establish what is called a brokered trust relationship through obtaining tokens from STS, Secure Token Service, to authenticate their interactions.

Their presentation next focused on the challenges of integrating both businesses and consumers and the road map for the future. The key issue is establishing a contract through data structures. When it comes to XML schema interoperability, they summed up their advice to developers in the memorable acronym, KISS: Keep Interoperable Schemas Simple. They recommend a simple set of de-facto profiles: xs:sequence, xs:element, wrapped arrays, etc.
There are functional and established complex schemas available and perhaps necessary in scenarios, but Gupta recommended caution in using them.

Schemas should be used as data type descriptions, not as validation mechanisms. Avoid complexity unless it’s required, and avoid schema constructs that do not map well onto programming languages.

They turned to the issue of binary attachments which Gupta acknowledged has had a “bumpy road over the last few years”. xs:base64Binary is interoperable, but comes with a high processing cost and 30% extra message size.

The industry has fallen into two camps: one has gone with SOAP attachments, while the other adopted DIME (Direct Internet Message Encapsulation). Both push the binary data outside of the SOAP envelope. SwA, which is SOAP with attachments, has low interoperability, with attachments outside the SOAP body, and suffers from lack of composition with other web services protocols. DIME has the same problems as SwA.

So what to do? MTOM (Message Transmission Optimization Mechanism) comes to the rescue. MTOM works in a simple manner. It is conceptually like a SOAP envelope, but just before the SOAP envelope hits the wire the binary part of the body is serialized as a separate MIME part.

Integrating Businesses

The key to business integration, not surprisingly, is reliable, secure messaging. With information moving over the web between services, there is a danger of information getting lost and a need for reliable security. Quote service reliability requirements include reliable transfer of messages end-to-end, assurances that orders are not duplicated and secure composition.

They then presented a demo of reliable messaging in which a .NET wholesale service was interacting with a Sun managed Java retail quote service in a reliable and secure manner.
Trust

They turned to the issue of WS-Trust and Security Token Services, which “arbitrate” trust through providing universal token/claim conversion, and support for arbitrary trust patterns in a decentralized manner -- anyone can be STS. They discussed Security Policy and Metadata Exchange whereby
services specify what claims types are required and consumers dynamically obtain tokens through the trust chain.

WCF

Finally, Gavrylyuk discussed Windows Vista Web Services, and the Windows Communication Foundation (WCF -- a.k.a. Indigo) which offers a runtime for building distributed applications. “InfoCards” visualizes a user’s digital identity, Active Directory Federation Services provide an infrastructure for identity and access. Windows Remote Management enables interoperable system management, and something called Web Services For Devices helps with Web Services-based devices interaction.

That's all for now, folks. Bare bones of a technical session but hopefully of some value.

For more meatier or vegy (if you're a vegetarian) details:

Windows Communication Foundation (a.k.a. Indigo)
http://msdn.microsoft.com/webservices/indigo/

GlassFish Community
https://glassfish.dev.java.net/

Web Services Interoperability Portals
http://msdn.microsoft.com/webservices/building/interop
http://mssoapinterop.org/ws/

Web Services Interoperability Blogs
http://pluralsight.com/blogs/kirillg/
http://blogs.msdn.com/dotnetinterop/
http://www.simonguest.com
http://weblogs.java.net/blog/arungupta/
http://weblogs.java.net/blog/haroldcarr/



Here we go! JavaOne is almost here!

Posted by hiheiss on May 10, 2006 at 08:14 PM | Permalink | Comments (0)

Among the topics currently scheduled for my editorial beat:

-- The Slot Car Programming Challenge wherein developers get to test their skills with Real-Time Java. Standard 1/24 scale cars run around a track with 80 sensors spread along its length with a power supply controlled by an A/D converter driven from a workstation. Contestants have to write software that controls the car while going as fast as possible. The sensors are simple photocell gates like those used to detect paper moving through a printer. The Real-Time Java program senses the track position of a slot car and sets the voltage to the track -- and thus the speed of the car. Attendees with the 3 shortest lap times will have a final run-off during James Gosling’s keynote on Friday.

-- The activities of Tommy, the autonomous, unmanned Java technology-powered robotic dune buggy, who will be making myriad appearances. Tommy's software is built on a Java technology-based platform called the Mobile Autonomous X-bot (MAX) developed by Perrone Robotics, Inc. (PRI). PRI-MAX runs on the Java Platform, Standard Edition (Java SE, formerly known as J2SE), and uses the Java Communications API, while Tommy's microprocessors rely on a hardware-based Java Virtual Machine (JVM) running Java Platform, Micro Edition (Java ME, formerly known as J2ME).

-- The always-lively discussion at the Fireside Chat wherein JavaOne conference Alumni get to engage with Java luminaries.

-- Sun’s Project Tango which addresses interoperability between applications built on Microsoft's Web Services Communications Foundation (WCF, a.k.a. Indigo) and those built with Sun's Java Web Services technologies.

-- SOA and developments in open source.

-- Twelve Reasons to Use NetBeans Software.

Plus numerous other sessions, along with exhibits in the Pavilion and the flexibility to go where the action is. I already feel sleep deprived!



RTSJ and the JavaOne Slot Car Challenge

Posted by hiheiss on April 07, 2006 at 02:04 PM | Permalink | Comments (0)

I recently conducted an interview with Sun's Greg Bollella that debunks some myths about the difficulties of Real-Time Java and touts the coming Slot Car Challenge at JavaOne, which will give developers a chance to write some RTSJ code and see if can guide a slot car around a track with speed and accuracy -- it should be fun. Greg believes that "The Slot Car Challenge at the 2006 JavaOne Conference will prove that anyone can program with RTSJ,” and insists that programming in Real-Time Java is "more like bicycle science than rocket science". Anyone want to ride the bicycle?

Conscientious Software

Posted by hiheiss on March 30, 2006 at 03:35 PM | Permalink | Comments (1)

Conscientious Software: Part One of a Conversation with Sun Microsystems Laboratories' Ron Goldman Here's a rich IMHO interview with Sun's Ron Goldman by yours truly. Ron's a senior staff engineer at Sun Labs who is working with Richard Gabriel to envision a new software model. As we move into a world of massive software interdependence where standalone apps are on the way out, Ron wants to develop ways to make "large systems more robust, stable, and better able to take care of themselves." He wants software to start using cpu cycles "to actively monitor its own activity and environment, to continually perform self-testing, to catch errors and automatically recover from them, to automatically configure itself during installation, to participate in its own development and customization, to pay attention to how humans use it and become easier to use over time, and to protect itself from damage when patches and updates are installed." Are you enticed by his vision?...

Meet Java Developer, Arun Gupta

Posted by hiheiss on March 20, 2006 at 10:18 AM | Permalink | Comments (0)

A "Meet the Engineer" interview I did with Java developer Arun Gupta of Sun might be worth checking out. Arun has useful insights about programming in India and the US, the challenges of developing software, Java APIs for XML Web Services Addressing (JAX-WSA), and efforts to get Sun Microsystems and Microsoft on the same page. He's a smart guy and has a patent related to XML and has several patents pending.

Seeing Shouldn't Be Believing or the World According to Josh Bloch

Posted by hiheiss on March 13, 2006 at 03:18 PM | Permalink | Comments (1)

Please check out the interview

http://java.sun.com/developer/technicalArticles/Interviews/bloch2006_qa.html

I had the pleasure to do
with Google Java architect,
Joshua Bloch, in which he
discusses his latest book,
"Java Puzzlers," written with
Neal Gafter. He models puzzlers
on optical illusions; you look
at a piece of Java code and
see one thing, but then on
closer inspection you realize
your mind has deceived you. The
idea is to trick the mind into
making a mistaken assumption
about code; you see your
mistake and will hopefully
never make it again. With optical
illusions, Bloch claims, understanding
how the illusion works does not change
the illusion. But if you understand
how a "code illusion" works,
you can stop making that mistake,
and spot it in future code that you review.

Bloch claims that most
of the puzzlers were derived
from real experiences of developers
and that the biggest problem for
developers is unwarranted optimism.

Speaking of unwarranted optimism,
it's fascinating that they fell into
their own trap in one of the solutions
to a puzzler that turned out to be broken;
they had to include an errata in their book
correcting it. Bloch argues that no one is immune.

Josh also makes some interesting comments about
language design decisions.

I totally enjoyed interviewing him.
Besides being super smart, he's an
all-around great guy.



Meet the Engineer Q&A on java.sun.com

Posted by hiheiss on March 10, 2006 at 04:54 PM | Permalink | Comments (0)

Please check out this Q&A:

http://java.sun.com/developer/Meet-Eng/ohair/

I did with Kelly O'Hair, senior staff
engineer in JDK (Java Development Kit) Core Serviceability.

He was really fun to interview.

Asked if he ever feels a sense that he's
created something beautiful when
he writes code, O'Hair said,
"Well, more like 'not ugly.'
There's a gray zone between ugly
and beautiful. Simple is beautiful."

Kelly is a java.net blogger so check out his blog
too to get to know him better if you haven't already.



Putting the Server in Your Pocket

Posted by hiheiss on June 29, 2005 at 11:07 PM | Permalink | Comments (5)

At the June 29, Wednesday morning Platinum session, held from 8:30 to 9:15, Nokia Chief Technology Officer and Senior Vice President Pertti Korhonen provided a vision of the future that promises to take Sun's motto "The network is the computer" to another level, by putting the server in your pocket.

Steve Meloan does a really good job of covering the technical moves Nokia and the industry are making to enable this here:

http://java.sun.com/javaone/sf/sessions/general/nokia_wednesday.j sp

so that allows me to wax philosophical :) in this blog.

It's a remarkable all-too-implicit vision of a world where extraordinary access to information and communicative power are available anytime, any place. Anyone can contact anyone and information about anything is at your fingertips. That is where we are headed. In another year or so mobile Java devices will be in the hands of a billion people, absolutely awesome. The "power of Java everywhere" is no hype; it's fast becoming real. There is no question that in many domains of life, from medicine to meter readers to industry to friendship and love, it's great. But I remember Jon Krakauer's book, Into Thin Air about a disastrous climb of Mt Everest in which many people died. What was almost unbearably poignant was the story of the leader of the climb, an Australian who found himself stranded at the peak in a severe blizzard at which he had the capacity to speak to his wife in Australia by cell phone, but was unable to get down from the summit before freezing to death. Technology could enable this man to talk to his wife as he was dying but it could not overcome the dubious risk-taking judgment that led to disaster.

It's tempting to make this story symbolic of something or other - I don't really know what. Maybe something like the story of the pilot of the plane who doesn't know where he is going but is proud of the fact that he is breaking all speed records. It's all happening so fast, and there is always the law of unintended, unforeseeable consequences.

I found myself wanting Korhonen, and everyone else, to get specific about how this technology can help us. The vision can't just be technological, but one that looks more deeply into the nuances of the implications for human life.

But perhaps that's what the theme of this conference is hinting at with its emphasis on the word, share.

Exposing Java Technology Performance Myths

Posted by hiheiss on June 29, 2005 at 10:48 PM | Permalink | Comments (4)

Here I am at TS-3268, "Java Technology Performance Myths Exposed," with Cliff Click, of Azul Systems. Azul, founded in 2001, advertises itself as pioneering "the industry's first network attached processing solution, designed to unbound compute resources for virtual machine based applications. Without any application level modifications, binary compatibility requirements or operating system dependencies, this fundamentally new approach eliminates the need to capacity plan at the application level and dramatically lowers the cost and complexity associated with the traditional delivery of computing resources."

Click enumerated six performance myths. What follows are the basics.

Myth One: The notion that you can add the "final" key word and your code will run faster. The assumption is that by adding the "final" key word I allow the JVM to inline and do the right thing. Not true. "Final" won't make your code run faster.

Myth Two: Try/catch blocks are free or they're very expensive. Google gives both bits of advice - that it was free or kills performance. Both are wrong. It is both very cheap and very expensive - depending. Advice: Don't put try/catches in very tight array loops. Otherwise it's more or less free.

Myth Three: Use RTTI - Run-Time Type Info. Compared RTTI versus instance-of if-tree versus virtual call. RTTI makes for really ugly code - it is fast though, so only use it if you're desperate for that last bit of performance.

Myth Four: Synchronization is very expensive. The truth is synchronization is not free, but it's no longer so expensive. It's gotten a lot cheaper over the years.

Myth Five: Object pooling works. The idea is that we can reuse objects by pooling them on and off free lists instead of using new and letting the garbage collector pick them up. Once you have more than one thread going off the pool, you need a synchronized free list, which has costs. If the list gets hot and contended, you can get scaling bugs. It gets complicated too fast and is not worth it for small to even moderate sized objects. Use it only for large objects.

Myth Six: The cost of the revisions to Java Platform Standard Edition 5.0 are substantial. Not true. Enums, autoboxing and varargs are mostly free.

Cliff wrapped up his session with a few final observations:

GC is getting cheaper and pretty efficient, and less intrusive. There are still scaling problems with large heaps.

Object pooling will remain viable for largest objects with high costs. Small objects will get even cheaper.

Click closed with one piece of advice: "If you take away only one thing from his talk, it would be that modern JVMs favor common usage patterns and clean code."



Project Looking Glass: An Expanding Universe on Your Desktop

Posted by hiheiss on June 29, 2005 at 10:31 PM | Permalink | Comments (3)

I'm at TS-7992 where Project Looking Glass (LG3D), a Java technology-based open source project that brings a richer user experience to the desktop through 3D windowing and visualization capabilities, is being presented to an audience of, I guesstimate, 800 people. LG3D sprang from the very creative heart and mind of Sun's Hideya Kawahara. Recognizing that desktops had not changed substantially in 20 years, he set out to make them more aesthetically appealing and powerful. Operating on the assumption that the next user interfaces would be 3D, he initiated a side project that would consume at least two hours a day of his spare time, plus most of his weekends and holidays for more than a year before taking hold at Sun. To put it mildly, it has taken hold. It's the most popular "app" on java.net (http://lg3d.dev.java.net) with 26,600 source code downloads, plus 600 members (and counting) since the 2004 JavaOne Conference where it was open sourced.

So what's the latest? Hideya and Paul Byrne, LG3D project owners, demo'ed a range of 3D images, a music player, scenes in which you could alter the backgrounds with a click, "Alice" an award winning 3D media player (http://alice.dev.java.net) that is the first to utilize the 3D capacity of Looking Glass, and more.

CosmoSchedulerD, a three-dimensional application running on LG3D software, created by developers at the Kyushu Institute of Technology in Japan, won a Duke's Choice Award (http://java.sun.com/javaone/sf/dukes_choice_awards.jsp). As a schedule book, it recreates outer space, with your personal solar system built in by arranging the planets according to their dates. The front of the orbit represents the current time, while the size of the planet symbolizes an appointment's importance, which makes it hard to forget an event even a few light years from now. CosmoSchedulerD contains features that ordinary schedule notebooks don't have, such as automatic scheduling, networking, and a workspace manager. Imaginative desktops seem to inspire even more imaginative apps to be built on them.

(I can't escape the feeling that talking about innovations on a gorgeous 3D desktop is like a donkey carrying a load of books. Have to shake it off. By all means go check out "Philco" running LG3D, the mock-up on the cell phone, and LG3D on a 3D LCD display, and all the rest on the pavilion floor!)

Hideya and Paul gave a brief summary of how to create a "deep" 3D environment. It's built on Java 3D with specialized classes that include a component model, animation system and SceneManager interaction. The LG3D 0.7 release has just arrived. There is now WebStart support (http://lg3d-webstart.dev.java.net) for running the "developers" mode of Looking Glass. It operates in application mode so LG3D can run on top of a user's existing desktop. Java 3D 1.4 now enables performance improvements like shader support. It has Open Solaris support.

In the pipeline is tool integration, a visualization library, and "SwingNode" support. There will be greater inclusion of identity and collaboration features and a more task-oriented UI.

To run it: http://lg3d-webstart.deve.java.net

To get it: http//lg3d-core.dev.java.net

To learn more about LG3D: http://java.sun.com/developer/technicalArticles/javaopensource/plg .html

http://java.sun.com/developer/technicalArticles/J2SE/Desktop/look ingglass/



Shale: The Next Struts?

Posted by hiheiss on June 29, 2005 at 09:57 PM | Permalink | Comments (4)

I'm at TS-7393 along with a pretty packed room of, I estimate, 700+ attendees. All the sessions that I've gone to have been well attended with a serious but enthusiastic-looking group of folks it appears who ask smart questions in the Q & A's. The session is titled "Shale: The Next Struts?" with Sabreware's David Geary and Sun's Craig McClanahan. Craig is Strut's inventor and David, Struts template tag library inventor, which was the inspiration for creating Tiles, one of Struts most popular features. Shale is the new kid on the block in the web application frameworks space, with David and Craig being two of the three leading original contributors on Shale. A lot of people want to know: What's the deal with Struts and JavaServer Faces (JSF), and Struts and Shale? A lot of uncertainty surrounds the topic. It is impossible to predict where it is all headed

McClanahan presents the rationale for Shale. Shale is unique among web application frameworks in that it starts by assuming that JSF exists. Recognizing that with a little tweaking you can turn JSF into a completely functional web app framework, he decided to see if something as popular as Struts could be created. So he proposed Shale as the architecture for Struts 2.0 to Struts developers, which did not entirely sit well, given the focus on backwards compatibility and support for existing Struts users. They did accept Shale as a Struts sub-project, so it is officially part of the Struts environment. The idea is to grow a community around Shale that is already used to the idea of using web app frameworks in developing. He is quick to point out that Shale has zero direct relationship with the Struts 1.0 code. Shale is all new code based on the assumption that JSF exists; it skips the step of re- implementing the features that are already there, like validation and request processing.

Features in Shale include web flow, so developers can organize a dialogue that is longer than a request but shorter than a session. There is client-side and server-side validation but with JSF components. Shale is integrated with Spring to enable transparent use of Spring's bean factory to create managed beans. David Geary has been extracting Tiles out of the Struts core, so it is independent of the underlying framework and can be used by any framework more easily. Shale will take advantage of that. Primary subtrees is another way to perform reuse that will function through a specialized library called "Play". McClanahan pointed out that a lot of people dislike Struts because it likes JavaServer Pages (JSP). JSF likes JSP as well, but JSF has components as a Java API, and developers can plug in a different view handler to use something different. With Shale, they've created an environment that looks like Tapestry with a standard HTML file for the markup presentation. It has a test framework to make it easy to test the view controller and other implementations.

He is quick to point out that, although they could use Shale to create another JSF component library, that is not their goal. The components they are creating are only ones that interact directly with the framework's facilities. Anyone's JSF components will work in Shale - why reinvent the wheel? The five tags within Shale are: token tags to catch duplicate submits; a subview for extra value-add services for a dynamically included page as well as the main page; a commonsValidator tag used to integrate the commonsValidator rules; a validator script so developers can point to the Java script so they don't have to load it on every page. and a clay tag used for parameterized subtrees.

JSF as an architecture has extension points that Shale takes advantage of. The Spring integration is a custom variable resolver and looks at the first word in an expression like "customeraddress.city" -- if a customer does not exist will create the bean for you. By default, JSF will look in the managed beans definitions, but the extension checks for a bean factory as well. Similar facilities enable access to the Java Naming and Directory Interface (JNDI) context. The navigation management is encapsulated in a specialized dialog navigation handler. A specialized view handler enables developers to treat a Tile name as a view ID to reduce work

So where is all this headed? McClanahan presents three scenarios. First, it is possible that Struts developers will see that Shale is becoming popular and choose it as Struts 2.0. Second, it could become a separate Apache project - synergy exists with the Apache MyFaces community that is building both an implementation of JSF and some interesting components to go with it. All of the JSF-related things could be encapsulated into a single project. A third possible future is aware of how long it takes to build a Java standard in the Java Community Process (JCP) - almost two years to build JSF 1.0. Shale can be seen as an experiment to see if its facilities make sense in a future JSF release, perhaps in JSF 2.0 time frame. The future is unclear and ultimately in the hands of developers.

An Interview with Craig McClanahan

http://java.sun.com/developer/technicalArticles/Interviews/jsf_mc Clanahan.html

David Geary's Blog

http://jroller.com/page/dgeary

Craig McClanahan's Blog

http://blogs.sun.com/roller/page/craigmcc

A Cool MP3 Player at the SwingLabs Exhibit

Posted by hiheiss on June 29, 2005 at 10:19 AM | Permalink | Comments (1)

I’m at Exhibit #1111, Swing/Labs JDesktop Network Components (JDNC). It’s a Sun Microsystems project that allows experimentation with extensions to existing Java Foundation Classes/Swing API components, new JFC/Swing components and various desktop related technologies like Java 2D, AWT. I’m talking now with Sun’s Roman Guy, who explains, “We experiment with a number of projects containing JDNC and Swing components, all of which sit on top of Swing and add extra features, like transparency or animation. There are data-aware components that make it very easy to find data from a database or an XML file, directly to the UI. You have almost nothing to do -- everything is done for you in the code. You just choose the source of code and – that’s it.”

The source code is available on java.net, (http://www.java.net/) as part of the LGPL license. The idea is to explore new ideas in Swing components that may one day be part of the JDK, like various filtering, highlighting and searching features. “It’s a playground for the Swing team,” explains Guy.

Next to Roman, is Sun’s Richard Bair, operating a SwingLabs desktop network component demo, who explains, “We’ve created a music player that reads the music libraries of a very popular music player and will play any MP3 file that you have in your library. The interesting thing we’ve done is show off some of the cool features in our Swing X project, especially the data binding. First, you see the finished project, a nice music player with ‘play,’ ‘previous,’ and ‘next’ buttons and a search field. We have a lot of music and custom cell renderers and so on. On Thursday, June 30, this will go public as: joplin.dev.java.net – Joplin, as in Scott Joplin, is the name of our music player. We have a list of music and a collapsible panel -- you click a button and the music screen comes down as an animated effect. As you select different songs, you notice that the title, album, and artist genre info get updated.”

The screen displays a cool album cover.

“It looks fancy for a demo, but a lot of it is stock components from the Swing X project we put to use here,” says Richard. “We have a JX image panel component, which is nothing more than a component that knows how to extract the image art from an MP3. It’s pretty simple stuff. This table is a normal JX table and a little browser that lets you walk in 3D through all of the album covers in your music library. It’s all implemented in Java 2D, very fast. Once you get your song, you can listen to it. Another screen was written in Java 2D, we call Zoomy; this panel can be retrieved from another open source project on java.net that is called ping.dev.java.net. A search field enables you to filter by artist, album, genre and song. This will be part of James Gosling’s keynote on Thursday.”

Neat – I got a sneak preview.

Great work! Let’s hope it finds its way into the JDK. And don’t forget Gosling’s Thursday morning keynote.



Celebrating Java Technology Through Art

Posted by hiheiss on June 29, 2005 at 10:14 AM | Permalink | Comments (3)

It’s so inspiring to watch gifted artists at work. Their art is alive with color and imagination. Sun brought six gifted artists to the 2005 JavaOne Conference with the goal of raising $5000 for the Foundation for a College Education (FCE) of East Palo Alto, California, which Sun has supported for ten years, about as long as Java technology has existed. All during that time, Sun employees have volunteered their time tutoring students to help them become the first of their families to graduate from high school or college. This year, silent auctions take place until noon every day of the JavaOne conference through Wednesday and then Wednesday night the live auction occurs at the After Dark party from 7:45 to 8:15 in Hall A prior to comedian Dennis Miller’s performance.

What exactly is Java-inspired art? The idea is that Java developers are also artists who call upon inspiration and the creative imagination in creating their code, an insight that Sun’s Richard Gabriel has articulated as well as anyone. (http://java.sun.com/features/2002/11/gabriel_qa.html) The presence of the artists at the 2005 JavaOne Conference implicitly confirms what Gabriel says:

’Writing software should be treated as a creative activity. Just think about it -- the software that's interesting to make is software that hasn't been made before. Most other engineering disciplines are about building things that have been built before. People say, "Well, how come we can't build software the way we build bridges?" The answer is that we've been building bridges for thousands of years, and while we can make incremental improvements to bridges, the fact is that every bridge is like some other bridge that's been built. Someone says, "Oh, let's build a bridge across this river. The river is this wide, it's this deep, it's got to carry this load. It's for cars, pedestrians, or trains, so it will be kind of like this one or that one.’ They can know the category of bridge they're building, so they can zero in on the design pretty quickly. They don't have to reinvent the wheel.”

Gabriel points out that we’ve only been building software for 50 years and each time we do it, it’s fairly new. Gabriel says we should train developers the same way we train painters and poets. Sounds good to me.

The artists:

Tim Gaskin of San Francisco(http://timgaskin.homestead.com/index.html) said this about his work: “Besides the fact that I am first and foremost a colorist, my paintings are about how celebrities stand at premieres wearing hundreds of thousands of dollars worth of clothes and jewelry and get their picture taken in front of logos which are then sent out all over the world. They represent brands, and even become them because they are so overexposed."

Graffiti artist VULCAN, from the South Bronx area of Manhattan, has work exhibited in the Graffiti Hall of Fame (http://www.graffitihalloffame.org/) in New York City.

New Yorker Eric Orr, (http://www.bravemind.com/ericart/ericartindex.html) also a noted graffiti artist, got his start painting graffiti on the New York subway system. Orr, who has made a name for himself as a graphic artist designing logos for entertainers, boasts an impressive list of clients, including Afrika Bambaataa, The Cosby Show, Public Enemy, Fat Joe and Jive Records.

From crayons to krylon, Leon “Tes One” Bedore (http://www.tesone.net/main.html) has been creating art on walls for the majority of his life. Tes One became a serious street artist in 1992, painting murals and graffiti art throughout the Tampa Bay, Florida, area. In 1999, expanding on his natural artistic abilities in line with the computer age, he began to develop compelling graphic design and web pages for a number of clients. Now, he combines all that he knows from his street-art roots and his digital design profession to create art that accurately reflects his perspective on the world around him.

Brian Ermanski or “BE” of Manhattan, often described as a naïve/ignorant/outsider artist and downtown living NYC legend, has sold more than 70 of the 110 paintings he has produced to date.

Casey O’Connell, currently of San Francisco by way of Florida, recently came to the attention of John Doffing, curator of The Start SOMA Gallery in San Francisco, where all of the paintings in her first group show sold.

Come watch artists in the midst of their creative process. I'm really tempted to bid on some of this art myself.





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