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Janice J. Heiss's BlogJ2EE ArchivesDancing While Gaming – Multitasking VMs on Real DevicesPosted 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. 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. An application is in the background when: -- Its displayable does not control the display. 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 long ‘Hot’ key press the foreground MIDlet will be Upon calling setCurrent(null) the MIDlet will be placed in the 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)
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 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 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 -- 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 -- The Display and Sound requires special handling.
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.
Where the Software Met the RoadPosted by hiheiss on May 19, 2006 at 03:53 PM | Permalink | Comments (0)It's day two of JavaOne '06, and I’m over at the Slot Car Racing Programming Challenge area, where the track is heating up. Developers are standing in line, some for the 20th or 30th time! to see if their latest tweaks will pan out as they hoped. A lot has been happening here. The ABC Morning News guys were here with their cameras. Developers are taken with the chance of being onstage with James Gosling and spending some time with him. Gosling himself has been trying out the slot cars off and on for a few days. Some contestants admit that the slot car race brings them back to their childhood. Developer aren’t exactly closet game junkies. I approach one, who asked to be referred to as “Turtle,” and ask him if this is harder than he expected. “It’s very difficult,” says Turtle. (Yes, the name gives away something about his times.) “I have no experience with real-time. There is a lot of tuning, a lot of unknown variables – every car runs a little different. So even if you tweak it right for one car, it may not work for the next. This is about my 15th attempt and I’ve missed two sessions already.” (I’m beginning to understand why he doesn’t want his real name used.) “I’m getting better each time, and finally made it into turn three.” When I ask him how this is affecting him he says he wants to build a race track in his home. “This is a lot of fun. Once your car runs, the times are posted for your machine and you can figure out how fast your car is going at each sensor point. You could copy and paste this if you wanted, but it would be preferable if they gave you all of your races together so you could analyze all of the numbers.” Turtle informs me that the man standing next to him is tied for the lead. His name is Peter Whitfield. “I’m probably the worst Java programmer here – I’m more of a manager than a programmer,” admits Whitfield. “It will be embarrassing if anyone looks at my code. I have no experience with real-time Java, though 20 years ago, I worked with real-time systems. This is a lot of fun and a good opportunity to see how the real-time Java stuff works. It’s easy.” Different strokes for different folks. Peter -- who is quite generous with his time as he keeps eyeing the monitor above the track listing the names of who's in the lead along with who is currently racing -- completed the race in 25.49 seconds somewhere around his 20th trial and estimates that maybe 10 or 12 people out of 100 have made it to the finish line without crashing. Clearly the hardest thing is just making it around the track. I ask him the secret to his success. “Keep it simple -- do the absolute minimum necessary to get the result,” Whitfield explains. “There are guys doing some very sophisticated algorithms but I have not actually modified the sample algorithm at all, I’ve just been changing the parameters. Nothing in this application has been hard. I have an engineering background rather than a pure software development background and this is about manipulating voltages to control the speed, and that’s second nature to me. So my background helps. I have only now started changing the way the real-time stuff works. Until now, I’ve only changed the parameters of the way the speed changes as it goes around the track, so a lot if it involves trying to figure out how, if I change the voltage in one place, it affects the speed in another. That’s what people are missing -- they don’t understand how if they go too fast in one part of the track, it will make the car unstable later. The Java side of it is very easy to pick up because we are given a sample program. We have not had to set up the framework for it. Real-time programming is about understanding physical systems; it's not as abstract as writing UI software. So you need to understand the physics of what you are trying to do and the timing.” Peter went on to say: “I learned that I don’t program in Java often enough, so I hope people aren’t looking over my shoulder when I look up Google to figure out how I do multi-dimensional arrays. You need to be aware of where you are putting your thread to sleep and where it will wake up and if you are doing it in more than one place you need to think of the different permutations and where it can all happen.” And what else is Peter doing at JavaOne?.. “I’ve spent way too much time here. I don’t have a boss so I can sit here and just have fun.” I talk to a few other contestants waiting their turn. Jonathan O’Keefe, who does database programming, is trying out real-time for the first time. And there is Ulrich from Denmark who does web applications and GUI stuff and business logic, and Michael from Germany who does desktop programming and Carl, an American, from a company called Triego Network Security, who manages security information. None have experience with real-time. The line ebbs and flows at various times, but there's always someone racing, and there are a lot folks sitting in front of the machines set up for them on which they work on their real-time programs. Only Carl admits to big ambitions. “At first,” says Carl, “I was over-complicating it by treating it like a J2ME product, but if you are very conservative about the objects you allocate, you can treat it as a regular Java program. You have to keep it simple and not allocate anything in the loop or you will run out of memory. I’m going to try to knock someone off the leader board -- I’ve just started with the base program so there is a lot of room for improvement.” Carl sees uses for real-time Java at his company, Triego. “We do some close to real-time work and try hard to keep our GC under control and use a concurrent generational collector, so the real-time Java technology is very interesting. We could find a lot of use for this technology in the work we do. It’s interesting and the applicability of the predictability of execution time is great.” As I walk away, I see that Robert Chu is tied with Peter Whitfield’s 25.49 seconds time while Richard Yee is third, at 26.18, and Rivera (I don't catch his first name) is fourth at 28.60. I wonder if any of these folks will be in the top three when James Gosling gives his keynote on Friday morning. Time and times will tell. Stay tuned. The winners will be announced and compete one final time at the Gosling keynote on Friday. Should be a lotta fun! Finally, here's a story about the Slot Car Racing Programming Challenge yours truly wrote over on java.sun.com: The 2006 JavaOne Conference Slot Car Racing Programming Challenge
Programming in Real-Time Specification for Java (RTSJ): A Conversation with Distinguished Engineer Greg Bollella Let's Make a Deal: Java and .Net Hold Hands Over Web ServicesPosted 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. 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. 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 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) GlassFish Community Web Services Interoperability Portals Web Services Interoperability Blogs RTSJ and the JavaOne Slot Car ChallengePosted 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 SoftwarePosted 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?... The Advantages of the Java EE 5 Platform: A Conversation with Distinguished Engineer Bill ShannonPosted by hiheiss on March 27, 2006 at 05:59 PM | Permalink | Comments (0)Here's an interview that yours truly recently did with Bill Shannon that you might find interesting. Bill's a Sun distinguished engineer and spec lead for Java Platform Enterprise Edition (Java EE). He discusses how the Java EE 5 platform (formerly J2EE) makes life easier for developers. "There are so many ways we've made life simpler for developers, it's hard to know where to start," said Shannon, who has been at Sun since 1982. Check it out and let me know what you think. Meet Java Developer, Arun GuptaPosted 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. Q&A with Kohsuke KawaguchiPosted by hiheiss on February 02, 2006 at 04:14 PM | Permalink | Comments (0)A new "Meet the Engineer" Q&A I did with a java.net blogger appears on java.sun.com here if you want to check it out: (http://java.sun.com/developer/Meet-Eng/kawaguchi/) I interviewed Kohsuke Kawaguchi, who has worked with XML schema languages since 2001, including specification work on RELAX NG He's a lively and imaginative guy who was an entrepreneur in high school and college in Japan. He has interesting things to say about schema languages, work ethic differences between the US and Japan, the Stapler and JAXB projects, and more. Putting the Server in Your PocketPosted 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 spso 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.Project Looking Glass: An Expanding Universe on Your DesktopPosted 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/craigmccCelebrating Java Technology Through ArtPosted 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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