bryan r hinton

Fast, High performance, database driven, application architectures that support true rapid development are little talked about. AOLServer, OpenACS, PostgreSQL, and TCL are such a combination. I was introduced to AOLServer and OpenACS in 2002 by a close friend who I grew up with. We built a very robust application architecture over the course of the following 6 years. PostgreSQL was sitting behind the AOLServer/OpenACS instance and AOLServer nicely managed the database connection pools. AOLServer is multi-threaded and internally handles TCL interpretation and execution. TCL makes heavy use of lists (implementation notes aside), so many LISP programmers have enjoyed working with it. The OpenACS developer toolbar is a tool that provides developers with access to various debugging and profiling information about their OpenACS application. It is a feature that is built into the OpenACS application framework and can be enabled or disabled depending on the needs of the developer. Once en...

 Dtrace on FreeBSD 8 - new server with no load # uname -msri FreeBSD 8.0-RELEASE-p3 amd64 DEV_A64_KERNEL From the OpenSolaris DTrace Toolkit # /usr/local/share/DTTraceToolkit/syscallbypid.d Tracing... Hit Ctrl-C to end. 77913 perl sigprocmask 48 1267 svscan stat 51 45001 httpd read 52 26063 python2.4 recvfrom 61 26922 sshd ioctl 69 27104 more read 69 26888 postgres getppid 78 26888 postgres gettimeofday 78 26888 postgres select 78 26889 postgres getppid 78 26889 postgres select 78 45001 httpd poll ...

FreeBSD Soft Updates with Journaling, ULE Scheduler Very good short interview with Jeff Roberson, FreeBSD Committer.Discussion on the addition of journaling to soft updates and the development of the ULE scheduler. BSD Talk Blog - Jeff Roberson (February 05, 2010) You can also listen on your Android device. Just download Google Listen from the marketplace. After you setup Google Listen on your Android Device, search for bsdtalk or FreeBSD from within Google Listen.

When objects in a single thread are loosely coupled and need to communicate with each other, Notifications allow you to broadcast messages on a synchronous or asynchronous basis and still retain object independence. When you implement Store Kit in your application, it is most likely a reasonable assumption that you want to re-use your in-app store in a future iPhone application without rewriting the object(s) that implement the SKPaymentTransactionObserver and SKProductsRequestDelegate protocols. We know that these objects receive asynchronous notifications via the delegate protocol(s) that they implement. So in a nutshell, the object that implements the SKProductsRequestDelegate protocol will receive a response asynchronously when the product identifier request that it previously sent is successfully processed. The payment transaction observer object, which is added as an observer to the payment queue upon application launch, again receives asynchronous notifications when there's ...

In the coming weeks, I plan on covering the development process from start to finish. I will be talking about code organization, memory management, useful xcode features, core data, performance optimization, debugging, iterative development, and any other useful topics that I come across. iLogMiles was approved by Apple for sale on the App store, on April 6, 2010. iLogMiles is free to download. The app quickly hit the #2 spot on the top free business apps list. The user can upgrade to the full version and purchase themes from within the free application. We utilized the Apple Store Kit framework to provide the in-app store. The Store Kit framework provides the necessary means to securely process payments from within the application. Products are identified via product identifiers. Apple clearly defines the types of products that may be sold via the Store Kit framework. More on this later but keep in mind that it is very important to read through all of the documentation. Over the next...

Categories are a powerful tool for extending the functionality of existing classes in Objective-C. However, it's important to follow Apple's guidelines when using them to avoid any undefined behavior. Categories allow you to extend the functionality of an existing class without subclassing. Before I get into an example, here are a few guidelines to follow when using categories. Apple recommends to not use categories to override methods in other classes, inherited classes, or other categories. Categories are not meant to add instance variables to classes either. If used in such contexts, the behavior of a program is undefined. Apple recommends using categories for adding functionality to large, existing classes and then grouping that functionality accordingly. Overriding existing Cocoa methods that are inherited from within the Cocoa hierarchy is a no-no as is extending methods that are already part of a category within the Cocoa hierarchy. Categories allow the addition of...

I was fortunate to attend the iPhone Tech Talk conference, hosted by Apple Inc. in San Jose last October, 2009. One of the sessions I attended was on Core Data. At a very high level, Core Data is an Apple™ software framework for storing data on the computer - namely, the iPhone and the Mac. Please note that I don't plan on covering database design theory in this post so I'm assuming a familiarity with it. Core data is an Object graph management and persistence framework. Core data maintains a graph of objects (otherwise known as a managed object graph or managed object context). References to managed objects are stored in the object graph. Core Data serializes these objects and persists them to a data store. Core data can use several different underlying data stores - xml, binary, sqlite. The managed object context is a key concept in Core Data, as it provides a proxy between the application objects and the underlying data store(s). The persistent store coordinator is respo...

UITableViews on the iPhone often contain a variable number of cells. The following code snippet should be helpful for those who need to iterate over a variable length table and subsequently read or set data model and cell state. //loop through cells in each section and make sure the data model is in sync NSInteger numSections = [self numberOfSectionsInTableView:someTable]; for (NSInteger s = 0; s < numSections; s++) { NSLog(@"Section %d of %d", s, numSections); NSInteger numRowsInSection = [self tableView:someTable numberOfRowsInSection:s]; for (NSInteger r = 0; r < numRowsInSection; r++) { NSLog(@"Row %d of %d", r, numRowsInSection); MyCell *cell = (MyCell *)[someTable cellForRowAtIndexPath: [NSIndexPath indexPathForRow:r inSection:s]]; DataModelObject *theObject = (DataModelObject *)[fetchedResultsController objectAtIndexPath: ...

OS X and iOS contain open source components. Open Source Components that ship with Mac OS X 10.6.2 and their corresponding Open Source Projects (src avail for dl/browse) - http://www.apple.com/opensource/ Open Source Components that ship with Mac OS X 10.6.2, iPhone OS 3.1.2 and Developer Tools 3.2.1 (source avail for dl) Also browseable by prior versions - http://opensource.apple.com The open source components are typically released under various open source licenses, such as the Apache License, the GNU General Public License, and the BSD License, among others. By including open source components, Apple is able to leverage the work of the open source community and provide a more robust and secure platform for its users. The open source components can also be used by developers to build applications for macOS and iOS, as well as for other platforms. On to Android...so what is it? Android is an open-source mobile operating system. It uses a modified Linux 2.6 Kernel - tuned for embedde...