Working with Data in ASP.NET 2.0 - Querying Data with the SqlDataSource Control
All of the tutorials we’ve examined so far have used a tiered architecture consisting of presentation, Business Logic, and Data Access layers. The Data Access Layer (DAL) was crafted in the first tutorial (Creating a Data Access Layer) and the Business Logic Layer in the second (Creating a Business Logic Layer). Starting with the Displaying Data With the ObjectDataSource tutorial, we saw how to use ASP.NET 2.0’s new ObjectDataSource control to declaratively interface with the architecture from the presentation layer. While all of the tutorials so far have used the architecture to work with data, it is also possible to access, insert, update, and delete database data directly from an ASP.NET page, bypassing the architecture. Doing so places the specific database queries and business logic directly in the web page. For sufficiently large or complex applications, designing, implementing, and using a tiered architecture is vitally important for the success, updatability, and maintainability of the application. Developing a robust architecture, however, can be overkill when creating exceedingly simple, oneoff applications.
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Beginners C# Tutorial - Properties
Properties provide the opportunity to protect a field in a class by reading and writing to it through the property. In other languages, this is often accomplished by programs implementing specialized getter and setter methods. C# properties enable this type of protection while also letting you access the property just like it was a field. To get an appreciation for what properties accomplish, let’s take a look at how to provide field encapsulation by traditional methods.
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Java Collections Framework
This tutorial takes you on an extended tour of the Java Collections Framework. The tutorial starts with a few simple programming examples for beginners and experts alike, to get started with the Collections Framework quickly. The tutorial continues with a discussion of sets and maps, their properties, and how their mathematical definition differs from the Set, Map, and Collection definitions within the Collections Framework. A section on the history of Java Collections Framework clears up some of the confusion around the proliferation of set- and map-like classes. This tutorial includes a thorough presentation of all the interfaces and their implementation classes in the Collections Framework. The tutorial explores the algorithm support for the collections, as well as working with collections in a thread-safe and read-only manner. In addition, the tutorial includes a discussion of using a subset of the Collections Framework with JDK 1.1. The tutorial concludes with an introduction of JGL, a widely used algorithm and data structure library from ObjectSpace that predates the Java Collections Framework.
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A short Java RMI tutorial
This is a technical literature study which purpose is to describe the basic parts of Java Remote Method Invocation. Remote Method Invocation, abbreviated as RMI [SUN02, p2], provides support for distributed objects in Java, i.e. it allows objects to invoke methods on remote objects. The calling objects can use the exact same syntax as for local invocations. The Java RMI model has two general requirements. The first requirement is that the RMI model shall be simple and easy to use and the second requirement it that the model shall fit into the Java language in a natural way.
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MRG Messaging AMQP Programming Tutorial for C++, Java, and Python
MRG Messaging implements the AMQP specification 1, which was written to create an open standard for interoperable messaging. AMQP defines both a wire level protocol (the transport layer) and higher level semantics for messaging (the functional layer). It is completely free to use and is being developed by the AMQP Working Group. AMQP is currently in draft and will be submitted to a standards body once it is completed.
In AMQP, a connection represents a network connection, and a session represents the interface between a client and a broker. A session uses a connection for communication. Sessions may be synchronous or asynchronous.
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