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  • Howto use FB Graph to post a message on a feed (wall)

    - by qualbeen
    I have created an app, and now i want to post a message on one of my friends wall with use of the new Graph API. Is this do-able? I am already using oAuth and the Graph-api to get a list of all my friends. The API at http://developers.facebook.com/docs/api tells me to cURL https://graph.facebook.com/[userid]/feed to read the feed, but it also tells me howto post a message: curl -F 'access_token=[...]' -F 'message=Hello, Arjun. I like this new API.' https://graph.facebook.com/arjun/feed Ofcourse this doesn't work! And I can't find out why.. Here are my PHP-code: require_once 'facebook.php'; // PHP-SDK downloaded from http://github.com/facebook/php-sdk $facebook = new Facebook(array(appId=>123, secret=>'secret')); $result = $facebook->api( '/me/feed/', array('access_token' => $this->access_token, 'message' => 'Playing around with FB Graph..') ); This code does not throws any error, and I know my access_token are correct (otherwise i could't run $facebook-api('/me?access_token='.$this-access_token); to get my userobject. Have anyone out there sucsessfully posted a message using Graph-api? Then i need your help! :-)

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  • Using LinqExtender to make OData feed fails

    - by BurningIce
    A pretty simple question, has anyone here tried to make a OData feed based on a IQueryable created with LinqExtender? I have created a simple Linq-provider that supports Where, Select, OrderBy and Take and wanted to expose it as an OData Feed. I keep getting an error though, and the Exception is a NullReference with the following StackTrace at System.Data.Services.Serializers.Serializer.GetObjectKey(Object resource, IDataServiceProvider provider, String containerName) at System.Data.Services.Serializers.Serializer.GetUri(Object resource, IDataServiceProvider provider, ResourceContainer container, Uri absoluteServiceUri) at System.Data.Services.Serializers.SyndicationSerializer.WriteEntryElement(IExpandedResult expanded, Object element, Type expectedType, Uri absoluteUri, String relativeUri, SyndicationItem target) at System.Data.Services.Serializers.SyndicationSerializer.<DeferredFeedItems>d__0.MoveNext() at System.ServiceModel.Syndication.Atom10FeedFormatter.WriteItems(XmlWriter writer, IEnumerable`1 items, Uri feedBaseUri) at System.ServiceModel.Syndication.Atom10FeedFormatter.WriteFeedTo(XmlWriter writer, SyndicationFeed feed, Boolean isSourceFeed) at System.ServiceModel.Syndication.Atom10FeedFormatter.WriteFeed(XmlWriter writer) at System.ServiceModel.Syndication.Atom10FeedFormatter.WriteTo(XmlWriter writer) at System.Data.Services.Serializers.SyndicationSerializer.WriteTopLevelElements(IExpandedResult expanded, IEnumerator elements, Boolean hasMoved) at System.Data.Services.Serializers.Serializer.WriteRequest(IEnumerator queryResults, Boolean hasMoved) at System.Data.Services.ResponseBodyWriter.Write(Stream stream) I've kinda narrowed it down to a issue where LinqExtender wraps every returned object, so that my object actually inherits itself - thats at least how it looks like in the debugger. These two queries are basicly the same. The first is the legacy-api where the OrderBy and Select is regular Linq to Objects. The second query is a "real" linq-provider made with LinqExtender. var db = CalendarDataProvider.GetCalendarEntriesByDate(DateTime.Now, DateTime.Now.AddMonths(1), Guid.Empty) .OrderBy(o => o.Title) .Select(o => new ODataCalendarEntry(o)); var query = new ODataCalendarEntryQuery() .Where(o => o.Start > DateTime.Now && o.End < DateTime.Now.AddMonths(1)) .OrderBy(o => o.Title); When returning db for the OData feed everything is fine, but returning query throws a NullRefenceException. I've tried all kind of tricks and even tried to project all the data into a new object like this, but still the same error return query.Select(o => new ODataCalendarEntry { Title = o.Title, Start = o.Start, End = o.End, Name = o.Name });

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  • Parsing a JSON feed from YQL using jQuery

    - by Keith
    I am using YQL's query.multi to grab multiple feeds so I can parse a single JSON feed with jQuery and reduce the number of connections I'm making. In order to parse a single feed, I need to be able to check the type of result (photo, item, entry, etc) so I can pull out items in specific ways. Because of the way the items are nested within the JSON feed, I'm not sure the best way to loop through the results and check the type and then loop through the items to display them. Here is a YQL (http://developer.yahoo.com/yql/console/) query.multi example and you can see three different result types (entry, photo, and item) and then the items nested within them: select * from query.multi where queries= "select * from twitter.user.timeline where id='twitter'; select * from flickr.photos.search where has_geo='true' and text='san francisco'; select * from delicious.feeds.popular" or here is the JSON feed itself: http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20query.multi%20where%20queries%3D%22select%20*%20from%20flickr.photos.search%20where%20user_id%3D'23433895%40N00'%3Bselect%20*%20from%20delicious.feeds%20where%20username%3D'keith.muth'%3Bselect%20*%20from%20twitter.user.timeline%20where%20id%3D'keithmuth'%22&format=json&env=store%3A%2F%2Fdatatables.org%2Falltableswithkeys&callback=

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  • Event feed implementation - will it scale?

    - by SlappyTheFish
    Situation: I am currently designing a feed system for a social website whereby each user has a feed of their friends' activities. I have two possible methods how to generate the feeds and I would like to ask which is best in terms of ability to scale. Events from all users are collected in one central database table, event_log. Users are paired as friends in the table friends. The RDBMS we are using is MySQL. Standard method: When a user requests their feed page, the system generates the feed by inner joining event_log with friends. The result is then cached and set to timeout after 5 minutes. Scaling is achieved by varying this timeout. Hypothesised method: A task runs in the background and for each new, unprocessed item in event_log, it creates entries in the database table user_feed pairing that event with all of the users who are friends with the user who initiated the event. One table row pairs one event with one user. The problems with the standard method are well known – what if a lot of people's caches expire at the same time? The solution also does not scale well – the brief is for feeds to update as close to real-time as possible The hypothesised solution in my eyes seems much better; all processing is done offline so no user waits for a page to generate and there are no joins so database tables can be sharded across physical machines. However, if a user has 100,000 friends and creates 20 events in one session, then that results in inserting 2,000,000 rows into the database. Question: The question boils down to two points: Is this worst-case scenario mentioned above problematic, i.e. does table size have an impact on MySQL performance and are there any issues with this mass inserting of data for each event? Is there anything else I have missed?

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  • uTorrent repeatedly downloads old files from the RSS feed

    - by Domchi
    So I set up uTorrent to automatically download torrents from EZTV search-based RSS feeds. And it works splendidly. I just set feeds to download automatically, and didn't set up smart episode filters or anything else in the uTorrent itself. However, from time to time something happens to EZTV feeds which makes uTorrent re-download every single torrent in every feed. I'm looking for a workaround.

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  • Looking to display a text RSS feed as Windows 7 desktop/background

    - by Matt
    I'd like to display an RSS feed (updating dynamically of course) on my Windows 7 desktop. The posts I've read about Windows 7 RSS backgrounds are all about displaying various background images delivered via RSS. What I'm looking for would be similar to the Windows XP/95 Active Desktop feature which allowed for web pages to be presented on the desktop background.

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  • A feed scanner that reads data

    - by kylex
    I don't know if this is the right place to ask this question, but... I need a scanner (paper feed scanner) where depending on either a barcode, or number, or some identifier on the paper being scanned, creates a PDF file with a name based on that identifier. For example: If I scanned a page with the number 12345 on the top-left of the page, a PDF file named 12345.pdf would be created. Any suggestions at all would be greatly appreciated!

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  • creating the icalendar feed and accessing it via webcal: protocal

    - by Sagar
    Hi i completed creating i calendar feed in asp.net mvc.Basically the op is the file with .ics extensions.I am able to open my file in mozilla sunbird(calendar reader software) and view the milestones lists.Now when i want to open it with google calendar i get an error.How can i synchronize mi ical file with google calendar.Do i need to use webcal:\ protocol to achive that.Basically my feed link should apper some thing like this webcal://proj2009.basecamphq.com/feed/global_ical?token=457bd123e18d instead of controller/action/id(which i have now).There aint enough resource on the web for this one.Anyone pls help. Thanks in Advance.

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  • ASP.NET C# Write RSS feed for Froogle

    - by Peter
    Hi, I'm trying to create a RSS 2.0 feed in ASP.NET C# with products to provide to Froogle. The RSS feed should look like: http://www.google.com/support/merchants/bin/answer.py?answer=160589&hl=en I'm using the SyndicationFeed and SyndicationsItems to create the feed. But I'm having trouble adding the extra elements like g:image_link. I try the extra elements like; syndicationItem.ElementExtensions.Add(new XElement("image_link", product.ImageLink).CreateReader()); This works, but how can I add the namespace xmlns:g="http://base.google.com/ns/1.0" to the first RSS tag and use this for the extension elements? Thank you

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  • 2-legged OAuth and the Gmail atom feed

    - by jdcotter
    We're trying to get 2-legged OAuth to work with the Gmail atom feed. We're using the Java library contributed by John Kristian, Praveen Alavilli and Dirk Balfanz. [http://oauth.net/code/] instead of the GData library. We know we have the correct CONSUMER_KEY and CONSUMER_SECRET, etc. becuase it works with the Contacts feed (http://www.google.com/m8/feeds/contacts/default/full) and have no problems. However with Gmail atom feed it always returns: HTTP/1.1 401 Unauthorized Any ideas? Should we try a different OAuth framework or does the problem lie on the Google side?

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  • Parsing XML feed into Ruby object using nokogiri?

    - by Galen King
    Hi all, I am pretty green with coding in Ruby but am trying to pull an XML feed into a Ruby object as follows (ignore the ugly code please): <% doc = Nokogiri::XML(open("http://api.workflowmax.com/job.api/current?apiKey=#{@feed.service.api_key}&accountKey=#{@feed.service.account_key}")) %> <% doc.xpath('//Jobs/Job').each do |node| %> <h2><%= node['name'].text %></h2> <p><%= node['description'].text %></p> <% end %> Basically I want to iterate through each Job and output the name, description etc. What am I missing? Many thanks, Galen

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  • How to produce a merged RSS feed (from DokuWiki and Serendipity)

    - by symcbean
    Hi, I've got an application developed on top of DokuWiki. I'd like to provide a 'News' page providing the latest updates from the internal RSS feed, some other feeds maintained in Serendipity and potentially other locations. Although its trivial to attach feed parsers to each one individually, I'd like to aggregate this into a single list (possibly a single RSS feed). Both the DokuWiki and Serendipity servers are not connected to the internet - so I can't use an external service for this - looking for code. Anybody got any ideas? TIA C.

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  • Parsing atom/rss feed containing multiple <link> tags with Haml on RoR

    - by fenderplayer
    So, firstly, heres an atom feed snippet which i am trying to parse: // http://somelink.com/atom <feed xmlns="http://www.w3.org/2005/Atom"> <entry> <title>Title Here</title> <link href="http://somelink.com/link1&amp;amp;ref=rss" rel="alternate" /> <link href="http://somelink.com/link2&amp;amp;ref=rss" rel="tag:somelink.com/apply_url"/> ... </entry> i pull the atom feed like so, // In controller index method @rss = SimpleRSS.parse open('http://somelink.com/atom') Then i output the response in the view, which i am writing using haml, as follows: - @rss.entries.each do |item| .title-div = item.title .title-link = item.link //outputs the first link I could run a second loop for the links but is there a way to get the second link without it? Like reading the "rel" attribute and outputting the correct link? How do i do this in haml/rails?

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  • How to model a social news feed on Google App Engine

    - by PEZ
    We want to implement a "News feed" where a user can see messages broadcasted by her friends, sorted with newest message first. But the feed should reflect changes in her friends list. (If she adds new friends, messages from those should be included in the feed, and if she removes friends their messages should not be included.) If we use the pubsub-test example and attach a recipient list to each message this means a lot of manipulation of the message recipients lists when users connect and disconnect friends. We first modeled publish-subscribe "fan out" using conventional RDBMS thinking. It seemed to work at first, but then, since the IN operator works the way it does, we quickly realized we couldn't continue on that path. We found Brett Slatkin's presentation from last years Google I/O and we have now watched it a few times but it isn't clear to us how to do it with "dynamic" recipient lists. What we need are some hints on how to "think" when modeling this.

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  • Facebook feed publishing form not appearing

    - by Arkid
    I am trying to publish feed through feed form but the feed form doesnot appear. However, the update happens and it happens twice. Also it says "Error thrown by application" in the dialog box. $message = "has invited you for all for hanging out wid him...the details being.."; //$facebook->api_client->stream_publish($message,null,null,$user,$user); $attachment = array( 'name' => 'Name', 'href' => 'http://www.facebook.com', 'caption' => 'Caption', 'description' => 'Description'); $attachment = json_encode($attachment); $action_links = array(array( 'text' => 'Action Link', 'href' => 'http://www.facebook.com')); $action_links = json_encode($action_links); $facebook->api_client->stream_publish($message, $attachment, $action_links); Please tell me what can be done here?

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  • Making JSON Feed Work Server to Server

    - by Oscar Godson
    I have a JSON feed (which I don't directly control, I have to ask the server admins to update it), that is returning NULL, or otherwise not working when I try to access it from another server. The actual feed works fine, but I can't get it to work like a normal API. Why can I use Flickr, WhitePages, Twitter, etc's JSON APIs, but for: http://portlandoregon.gov/shared/cfm/json.cfm It returns NULL in the browser when using JS. If I call it on the same server, it's fine though. If this is a server issue, what do I ask the admins to change, and if this is a local (browser) based issue, what am I doing wrong for this one feed that works for every other JSON API?

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  • RSS-Feed or XML-Stream?

    - by Maenny
    HI Folks, I am programming a website for online-reservation-management, preferably for holiday homes. I want to implement a service, which allows the user to pass all their occupation dates to other websites. My question is, what would be the most professional way to do this? Generate a XML-stream Create a valid RSS Feed I think that a XML file has the advantages of being straight to the point, without any information that noone needs. Webmasters of other websites surely prefer the structure of a simple XML file. On the other hand, when someone without programming knowledge wants to use the RSS-Feed with a feedreader or simply with the browser, it may be user-friendlier to use a RSS-FEED. What so you think, I'm unsure...? Greetz Maenny

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  • RSS feeds in Orchard

    - by Bertrand Le Roy
    When we added RSS to Orchard, we wanted to make it easy for any module to expose any contents as a feed. We also wanted the rendering of the feed to be handled by Orchard in order to minimize the amount of work from the module developer. A typical example of such feed exposition is of course blog feeds. We have an IFeedManager interface for which you can get the built-in implementation through dependency injection. Look at the BlogController constructor for an example: public BlogController( IOrchardServices services, IBlogService blogService, IBlogSlugConstraint blogSlugConstraint, IFeedManager feedManager, RouteCollection routeCollection) { If you look a little further in that same controller, in the Item action, you’ll see a call to the Register method of the feed manager: _feedManager.Register(blog); This in reality is a call into an extension method that is specialized for blogs, but we could have made the two calls to the actual generic Register directly in the action instead, that is just an implementation detail: feedManager.Register(blog.Name, "rss", new RouteValueDictionary { { "containerid", blog.Id } }); feedManager.Register(blog.Name + " - Comments", "rss", new RouteValueDictionary { { "commentedoncontainer", blog.Id } }); What those two effective calls are doing is to register two feeds: one for the blog itself and one for the comments on the blog. For each call, the name of the feed is provided, then we have the type of feed (“rss”) and some values to be injected into the generic RSS route that will be used later to route the feed to the right providers. This is all you have to do to expose a new feed. If you’re only interested in exposing feeds, you can stop right there. If on the other hand you want to know what happens after that under the hood, carry on. What happens after that is that the feedmanager will take care of formatting the link tag for the feed (see FeedManager.GetRegisteredLinks). The GetRegisteredLinks method itself will be called from a specialized filter, FeedFilter. FeedFilter is an MVC filter and the event we’re interested in hooking into is OnResultExecuting, which happens after the controller action has returned an ActionResult and just before MVC executes that action result. In other words, our feed registration has already been called but the view is not yet rendered. Here’s the code for OnResultExecuting: model.Zones.AddAction("head:after", html => html.ViewContext.Writer.Write( _feedManager.GetRegisteredLinks(html))); This is another piece of code whose execution is differed. It is saying that whenever comes time to render the “head” zone, this code should be called right after. The code itself is rendering the link tags. As a result of all that, here’s what can be found in an Orchard blog’s head section: <link rel="alternate" type="application/rss+xml"     title="Tales from the Evil Empire"     href="/rss?containerid=5" /> <link rel="alternate" type="application/rss+xml"     title="Tales from the Evil Empire - Comments"     href="/rss?commentedoncontainer=5" /> The generic action that these two feeds point to is Index on FeedController. That controller has three important dependencies: an IFeedBuilderProvider, an IFeedQueryProvider and an IFeedItemProvider. Different implementations of these interfaces can provide different formats of feeds, such as RSS and Atom. The Match method enables each of the competing providers to provide a priority for themselves based on arbitrary criteria that can be found on the FeedContext. This means that a provider can be selected based not only on the desired format, but also on the nature of the objects being exposed as a feed or on something even more arbitrary such as the destination device (you could imagine for example giving shorter text only excerpts of posts on mobile devices, and full HTML on desktop). The key here is extensibility and dynamic competition and collaboration from unknown and loosely coupled parts. You’ll find this pattern pretty much everywhere in the Orchard architecture. The RssFeedBuilder implementation of IFeedBuilderProvider is also a regular controller with a Process action that builds a RssResult, which is itself a thin ActionResult wrapper around an XDocument. Let’s get back to the FeedController’s Index action. After having called into each known feed builder to get its priority on the currently requested feed, it will select the one with the highest priority. The next thing it needs to do is to actually fetch the data for the feed. This again is a collaborative effort from a priori unknown providers, the implementations of IFeedQueryProvider. There are several implementations by default in Orchard, the choice of which is again done through a Match method. ContainerFeedQuery for example chimes in when a “containerid” parameter is found in the context (see URL in the link tag above): public FeedQueryMatch Match(FeedContext context) { var containerIdValue = context.ValueProvider.GetValue("containerid"); if (containerIdValue == null) return null; return new FeedQueryMatch { FeedQuery = this, Priority = -5 }; } The actual work is done in the Execute method, which finds the right container content item in the Orchard database and adds elements for each of them. In other words, the feed query provider knows how to retrieve the list of content items to add to the feed. The last step is to translate each of the content items into feed entries, which is done by implementations of IFeedItemBuilder. There is no Match method this time. Instead, all providers are called with the collection of items (or more accurately with the FeedContext, but this contains the list of items, which is what’s relevant in most cases). Each provider can then choose to pick those items that it knows how to treat and transform them into the format requested. This enables the construction of heterogeneous feeds that expose content items of various types into a single feed. That will be extremely important when you’ll want to expose a single feed for all your site. So here are feeds in Orchard in a nutshell. The main point here is that there is a fair number of components involved, with some complexity in implementation in order to allow for extreme flexibility, but the part that you use to expose a new feed is extremely simple and light: declare that you want your content exposed as a feed and you’re done. There are cases where you’ll have to dive in and provide new implementations for some or all of the interfaces involved, but that requirement will only arise as needed. For example, you might need to create a new feed item builder to include your custom content type but that effort will be extremely focused on the specialized task at hand. The rest of the system won’t need to change. So what do you think?

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  • Content Catalog for Oracle OpenWorld is Ready

    - by Rick Ramsey
    American Major League Baseball Umpire Jim Joyce made one of the worst calls in baseball history when he ruled Jason Donald safe at First in Wednesday's game between the Detroit Lions and the Cleveland Indians. The New York Times tells the story well. It was the 9th inning. There were two outs. And Detroit Tiger's pitcher Armando Galarraga had pitched a perfect game. Instead of becoming the 21st pitcher in Major League Baseball history to pitch a perfect game, Galarraga became the 10th pitcher in Major League Baseball history to ever lose a perfect game with two outs in the ninth inning. More insight from the New York Times here. You can avoid a similar mistake and its attendant death treats, hate mail, and self-loathing by studying the Content Catalog just released for Oracle Open World, Java One, and Oracle Develop conferences being held in San Francisco September 19-23. The Content Catalog displays all the available content related to the event, the venue, and the stream or track you're interested in. Additional filters are available to narrow down your results even more. It's simple to use and a big help. Give it a try. It'll spare you the fate of Jim Joyce. - Rick

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  • NightHacking with James Gosling

    - by Yolande Poirier
    Java Evangelist Stephen Chin is back on the road for a new NightHacking Tour. He is meeting with James Gosling at Kona, Hawaii, the launch base of the Wave Glider. The Glider is an aquatic robot which communicates real-time data from the surface of the ocean. It runs on an ARM chip using Java SE Embedded.  "During this broadcast we will show some of the footage of his aquatic robots, talk through the technologies he is hacking on daily, and do Q&A with folks on the live chat" explains Stephen Chin.  Sign up for the live stream on Wednesday, October 23rd at:  8AM Hawaii Time 11AM PST 2PM EST 20:00 CET Follow @nighthackingtv for the next Nighthacking events

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  • IBM Keynote: (hardware,software)–>{IBM.java.patterns}

    - by Janice J. Heiss
    On Sunday evening, September 30, 2012, Jason McGee, IBM Distinguished Engineer and Chief Architect Cloud Computing, along with John Duimovich IBM Distinguished Engineer and Java CTO, gave an information- and idea-rich keynote that left Java developers with much to ponder.Their focus was on the challenges to make Java more efficient and productive given the hardware and software environments of 2012. “One idea that is very interesting is the idea of multi-tenancy,” said McGee, “and how we can move up the spectrum. In traditional systems, we ran applications on dedicated middleware, operating systems and hardware. A lot of customers still run that way. Now people introduce hardware virtualization and share the hardware. That is good but there is a lot more we can do. We can share middleware and the application itself.” McGee challenged developers to better enable the Java language to function in these higher density models. He spoke about the need to describe patterns that help us grasp the full environment that an application needs, whether it’s a web or full enterprise application. Developers need to understand the resources that an application interacts with in a way that is simple and straightforward. The task is to then automate that deployment so that the complexity of infrastructure can be by-passed and developers can live in a simpler world where the cloud can automatically configure the needed environment. McGee argued that the key, something IBM has been working on, is to use a simpler pattern that allows a cloud-based architecture to embrace the entire infrastructure required for an application and make it highly available, scalable and able to recover from failure. The cloud-based architecture would automate the complexity of setting up and managing the infrastructure. IBM has been trying to realize this vision for customers so they can describe their Java application environment simply and allow the cloud to automate the deployment and management of applications. “The point,” explained McGee, “is to package the executable used to describe applications, to drop it into a shared system and let that system provide some intelligence about how to deploy and manage those applications.”John Duimovich on Improvements in JavaMcGee then brought onstage IBM’s Distinguished Engineer and CTO for Java, John Duimovich, who showed the audience ways to deploy Java applications more efficiently.Duimovich explained that, “When you run lots of copies of Java in the cloud or any hypervisor virtualized system, there are a lot of duplications of code and jar files. IBM has a facility called ‘shared classes’ where we put shared code, read only artefacts in a cache that is sharable across hypervisors.” By putting JIT code in ahead of time, he explained that the application server will use 20% less memory and operate 30% faster.  He described another example of how the JVM allows for the maximum amount of sharing that manages the tenants and file sockets and memory use through throttling and control. Duimovich touched on the “thin is in” model and IBM’s Liberty Profile and lightweight runtime for the cloud, which allows for greater efficiency in interacting with the cloud.Duimovich discussed the confusion Java developers experience when, for example, the hypervisor tells them that that they have 8 and then 4 and then 16 cores. “Because hypervisors are virtualized, they can change based on resource needs across the hypervisor layer. You may have 10 instances of an operation system and you may need to reallocate memory, " explained Duimovich.  He showed how to resize LPARs, reallocate CPUs and migrate applications as needed. He explained how application servers can resize thread pools and better use resources based on information from the hypervisors.Java Challenges in Hardware and SoftwareMcGee ended the keynote with a summary of upcoming hardware and software challenges for the Java platform. He noted that one reason developers love Java is it allows them to ignore differences in hardware. He stated that the most important things happening in hardware were in network and storage – in developments such as the speed of SSD, the exploitation of high-speed, low-latency networking, and recent developments such as storage-class memory, and non-volatile main memory. “So we are challenged to maintain the benefits of Java and the abstraction it provides from hardware while still exploiting the new innovations in hardware,” said McGee.McGee discussed transactional messaging applications where developers send messages transactionally persist a message to storage, something traditionally done by backing messages on spinning disks, something mostly outdated. “Now,” he pointed out, “we would use SSD and store it in Flash and get 70,000 messages a second. If we stored it using a PCI express-based flash memory device, it is still Flash but put on a PCI express bus on a card closer to the CPU. This way I get 300,000 messages a second and 25% improvement in latency.” McGee’s central point was that hardware has a huge impact on the performance and scalability of applications. New technologies are enabling developers to build classes of Java applications previously unheard of. “We need to be able to balance these things in Java – we need to maintain the abstraction but also be able to exploit the evolution of hardware technology,” said McGee. According to McGee, IBM's current focus is on systems wherein hardware and software are shipped together in what are called Expert Integrated Systems – systems that are pre-optimized, and pre-integrated together. McGee closed IBM’s engaging and thought-provoking keynote by pointing out that the use of Java in complex applications is increasingly being augmented by a host of other languages with strong communities around them – JavaScript, JRuby, Scala, Python and so forth. Java developers now must understand the strengths and weaknesses of such newcomers as applications increasingly involve a complex interconnection of languages.

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  • Session Report - Java on the Raspberry Pi

    - by Janice J. Heiss
    On mid-day Wednesday, the always colorful Oracle Evangelist Simon Ritter demonstrated Java on the Raspberry Pi at his session, “Do You Like Coffee with Your Dessert?”. The Raspberry Pi consists of a credit card-sized single-board computer developed in the UK with the intention of stimulating the teaching of basic computer science in schools. “I don't think there is a single feature that makes the Raspberry Pi significant,” observed Ritter, “but a combination of things really makes it stand out. First, it's $35 for what is effectively a completely usable computer. You do have to add a power supply, SD card for storage and maybe a screen, keyboard and mouse, but this is still way cheaper than a typical PC. The choice of an ARM (Advanced RISC Machine and Acorn RISC Machine) processor is noteworthy, because it avoids problems like cooling (no heat sink or fan) and can use a USB power brick. When you add in the enormous community support, it offers a great platform for teaching everyone about computing.”Some 200 enthusiastic attendees were present at the session which had the feel of Simon Ritter sharing a fun toy with friends. The main point of the session was to show what Oracle was doing to support Java on the Raspberry Pi in a way that is entertaining and fun. Ritter pointed out that, in addition to being great for teaching, it’s an excellent introduction to the ARM architecture, and runs well with Java and will get better once it has official hard float support. The possibilities are vast.Ritter explained that the Raspberry Pi Project started in 2006 with the goal of devising a computer to inspire children; it drew inspiration from the BBC Micro literacy project of 1981 that produced a series of microcomputers created by the Acorn Computer company. It was officially launched on February 29, 2012, with a first production of 10,000 boards. There were 100,000 pre-orders in one day; currently about 4,000 boards are produced a day. Ritter described the specification as follows:* CPU: ARM 11 core running at 700MHz Broadcom SoC package Can now be overclocked to 1GHz (without breaking the warranty!) * Memory: 256Mb* I/O: HDMI and composite video 2 x USB ports (Model B only) Ethernet (Model B only) Header pins for GPIO, UART, SPI and I2C He took attendees through a brief history of ARM Architecture:* Acorn BBC Micro (6502 based) Not powerful enough for Acorn’s plans for a business computer * Berkeley RISC Project UNIX kernel only used 30% of instruction set of Motorola 68000 More registers, less instructions (Register windows) One chip architecture to come from this was… SPARC * Acorn RISC Machine (ARM) 32-bit data, 26-bit address space, 27 registers First machine was Acorn Archimedes * Spin off from Acorn, Advanced RISC MachinesNext he presented its features:* 32-bit RISC Architecture–  ARM accounts for 75% of embedded 32-bit CPUs today– 6.1 Billion chips sold last year (zero manufactured by ARM)* Abstract architecture and microprocessor core designs– Raspberry Pi is ARM11 using ARMv6 instruction set* Low power consumption– Good for mobile devices– Raspberry Pi can be powered from 700mA 5V only PSU– Raspberry Pi does not require heatsink or fanHe described the current ARM Technology:* ARMv6– ARM 11, ARM Cortex-M* ARMv7– ARM Cortex-A, ARM Cortex-M, ARM Cortex-R* ARMv8 (Announced)– Will support 64-bit data and addressingHe next gave the Java Specifics for ARM: Floating point operations* Despite being an ARMv6 processor it does include an FPU– FPU only became standard as of ARMv7* FPU (Hard Float, or HF) is much faster than a software library* Linux distros and Oracle JVM for ARM assume no HF on ARMv6– Need special build of both– Raspbian distro build now available– Oracle JVM is in the works, release date TBDNot So RISCPerformance Improvements* DSP Enhancements* Jazelle* Thumb / Thumb2 / ThumbEE* Floating Point (VFP)* NEON* Security Enhancements (TrustZone)He spent a few minutes going over the challenges of using Java on the Raspberry Pi and covered:* Sound* Vision * Serial (TTL UART)* USB* GPIOTo implement sound with Java he pointed out:* Sound drivers are now included in new distros* Java Sound API– Remember to add audio to user’s groups– Some bits work, others not so much* Playing (the right format) WAV file works* Using MIDI hangs trying to open a synthesizer* FreeTTS text-to-speech– Should work once sound works properlyHe turned to JavaFX on the Raspberry Pi:* Currently internal builds only– Will be released as technology preview soon* Work involves optimal implementation of Prism graphics engine– X11?* Once the JavaFX implementation is completed there will be little of concern to developers-- It’s just Java (WORA). He explained the basis of the Serial Port:* UART provides TTL level signals (3.3V)* RS-232 uses 12V signals* Use MAX3232 chip to convert* Use this for access to serial consoleHe summarized his key points. The Raspberry Pi is a very cool (and cheap) computer that is great for teaching, a great introduction to ARM that works very well with Java and will work better in the future. The opportunities are limitless. For further info, check out, Raspberry Pi User Guide by Eben Upton and Gareth Halfacree. From there, Ritter tried out several fun demos, some of which worked better than others, but all of which were greeted with considerable enthusiasm and support and good humor (even when he ran into some glitches).  All in all, this was a fun and lively session.

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  • At the Java DEMOgrounds - Oracle Java ME Embedded Enables the “Internet of Things”

    - by Janice J. Heiss
    I caught up with Oracle’s Robert Barnes, Senior Director, Java Product Management, who was demonstrating a new product from Oracle’s Java Platform, Micro Edition (Java ME) product portfolio, Oracle Java ME Embedded 3.2, a complete client Java runtime optimized for microcontrollers and other resource-constrained devices. Oracle’s Java ME Embedded 3.2 is a Java ME runtime based on CLDC 1.1 (JSR-139) and IMP-NG (JSR-228).“What we are showing here is the Java ME Embedded 3.2 that we announced last week,” explained Barnes. “It’s the start of the 'Internet of Things,’ in which you have very very small devices that are on the edge of the network where the sensors sit. You often have a middle area called a gateway or a concentrator which is fairly middle to higher performance. On the back end you have a very high performance server. What this is showing is Java spanning all the way from the server side right down towards the type of chip that you will get at the sensor side as the network.” Barnes explained that he had two different demos running.The first, called the Solar Panel System Demo, measures the brightness of the light.  “This,” said Barnes, “is a light source demo with a Cortex M3 controlling the motor, on the end of which is a sensor which is measuring the brightness of the lamp. This is recording the data of the brightness of the lamp and as we move the lamp out of the way, we should be able using the server to turn the sensor towards the lamp so the brightness reading will go higher. This sends the message back to the server and we can look at the web server sitting on the PC underneath the desk. We can actually see the data being passed back effectively through a back office type of function within a utility environment.” The second demo, the Smart Grid Response Demo, Barnes explained, “has the same board and processor and is still using Java ME embedded with a different app on top. This is a demand response demo. What we are seeing within the managing environment is that people want to track the pricing signals of the electricity. If it’s particularly expensive at any point in time, they may turn something off. This demo sets the price of the electricity as though this is coming from the back of the server sending pricing signals to my home.” The demo had a lamp and a fan and it was tracking the price of electricity. “If I set the price of the electricity to go over 5 cents, then the device will turn off,” explained Barnes. “I can go into my settings and, in this case, change the price to 50 cents and we can wait a minus and the lamp will go off. When I change the pricing signal so that it is lower, the lamp will come back on. The key point is that the Java software we have running is the same across all the different devices; it’s a way to build applications across multiple devices using the same software. This is important because it fixes peak loading on the network and can stops blackouts.” This demo brought me back to a prior decade when Sun Microsystems first promoted  Jini technology, a version of Java that would put everything on the network and give us the smart home. Your home would be automated to tell you when you were out of milk, when to change your light bulbs, etc. You would have access to the web and the network throughout your home.It’s interesting to see how technology moves over time – from the smart home to the Internet of Things.

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  • At the Java DEMOgrounds - Java EE 7 WebSocket Early Access

    - by Janice J. Heiss
    At the packed and happening Java DEMOgrounds, I wandered over to check out Java EE Web Profile and Platform Technologies. Martin Matula, a Senior Development Manager at Oracle on the JavaEE/GlassFish team, responsible for the area of web services (including JAX-WS and JAX-RS), was demonstrating Java EE Web Profile and Platform Technologies.Matula was previewing some Java EE 7 WebSocket early access features via a group drawing application that showcases the upcoming JSR 356, “Java API for WebSocket”, which is the API for building RESTful web services and Server-Sent Events, an HTML5 feature. He emphasized that this is supported in Jersey, the reference implementation for JAX-RS, as well.“In this demo,” Matula explained, “I have a simple JavaScript front-end talking to the back-end deployed on GlassFish. It uses RESTful web services to get the list of drawings we have. I can create new drawings and the list is updated immediately using the Server-Sent Events, so the message is coming from the server to the client. Everything is getting updated live using WebSocket, which is the bi-directional communication new protocol in HTML5. This is using Project Jersey and Project Tyrus. Tyrus is the implementation of WebSocket protocol for Java. Jersey implements the RESTful APIs as well as the Server-Sent Events protocol.”

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