Juval Lowy

Juval Lowy

Juval Löwy is a software architect and the principal of IDesign, a consulting and training company focused on .NET architecture consulting and advanced .NET training. This article contains excerpts from his latest book (Programming .NET Components 2nd Edition (O'Reilly, 2005). Juval is a frequent presenter at development conferences and Microsoft's Regional Director for the Silicon Valley.
Over the last three years Juval has been part of the Strategic Design Review process for .NET 2.0.
Microsoft recognized Juval as a Software Legend as one of the world's top .NET experts and industry leaders.
Contact him at www.idesign.net

Articles Authored

  • .NET Interface-based Programming

    Last updated: Tuesday, February 19, 2019

    Published in: CODE Magazine: 2002 - May/June

    In component-based programming, the basic unit of use in an application is a binary-compatible interface.The interface provides an abstract service definition between the client and the object. This is in contrast to the object-oriented view of the world that places the object implementing the interface at the center. An interface is a logical grouping of method definitions that acts as the contract between the client and the service provider. Each provider is free to provide its own interpretation of the interface and its own implementation. To use a component, the client only needs to know the interface definition and have a binary component that implements that interface. This extra level of indirection between the client and the object provides for interchangeability between different implementations of the same interface, without affecting client code.

  • .NET Web Services Security

    Last updated: Tuesday, February 19, 2019

    Published in: CODE Magazine: 2003 - July/August

    Web services are all about connecting businesses in a standard and secure manner.For a real-life Web service, security is intrinsic to every facet of operation and no party would ever agree to interact with a non-secure Web service. Unfortunately, Web services security is still in its infancy; standards such as WS-I are just emerging and there is no built-in support in the development tools for them. That being said, there are quite a few programming techniques you can use today in .NET 1.1 to secure your Web services, and do so in a way that will ease the transition to future standards and protocols.

  • Asynchronous Calls in .NET

    Last updated: Tuesday, February 19, 2019

    Published in: CODE Magazine: 2003 - May/June

    When you make a method call on an object, typically you must block the client while the object executes the call, and control returns to the client only when the method completes execution and returns.However, there are quite a few cases where you want to call methods asynchronously?that is, you want control to return immediately to the client while the object executes the called method in the background, and then somehow let the client know when the method execution is completed. Such an execution mode is called asynchronous method invocation and the action is an asynchronous call. Asynchronous calls allow you to improve availability, increase throughput and performance, and make your applications more scalable.

  • Asynchronous Windows Forms Programming

    Last updated: Tuesday, February 19, 2019

    Published in: CODE Magazine: 2004 - March/April

    Windows Forms applications often require some sort of asynchronous invocation option.You rarely want to block the user interface while a lengthy operation executes in the background. Windows Forms pose a set of complicated design and implementation issues when it comes to asynchronous method invocation and multithreading due to the underlying Windows messages processing. Although .NET does provide a uniform asynchronous invocation mechanism (described in my article, "Asynchronous .NET Programming", CoDe Magazine, May 2003) you cannot apply it as-is in a Windows Forms application. To address this problem, the next version of .NET (version 2.0, code-name Whidbey) provides a new component designed to ease the task of developing asynchronous Windows Forms applications. This article starts by describing the current asynchronous programming model available to Windows Forms developers. Then, not only does this article describe the Whidbey solution, it also provides a .NET 1.1 implementation of the solution so that you can take advantage of this superior programming model today and ease the transition into Windows Forms 2.0 in the future.

  • C# 2.0 Code Refactoring

    Last updated: Tuesday, February 19, 2019

    Published in: CODE Magazine: 2004 - January/February

    The next version of C# will feature a code refactoring engine built into the Visual Studio environment.A term coined by Martin Fowler, code refactoring allows you to change the code structure without changing or affecting what the code itself actually does. For example, changing a variable name or packaging a few lines of code into a method are code refactoring. The main difference between C# 2.0 refactoring and a mere edit or find-and-replace is that you can harness the intelligence of the compiler to distinguish between code and comments, and so on. This article provides a preview of Visual C# 2.0 code refactoring, to be released with the next version of Visual Studio .NET, code-name Whidbey.

  • End DLL Hell with .NET Version Control and Code Sharing

    Last updated: Tuesday, February 19, 2019

    Published in: CODE Magazine: 2002 - July/August

    Component-oriented programming must allow for clients and components to evolve separately.Component developers should be able to deploy new versions (or just defect fixes) of existing components without affecting existing client applications. Client developers should be able to deploy new versions of the client application and expect it to work with older component versions. As a component technology, .NET must enforce version control, allowing for separate evolution paths and for side-by-side deployment of different versions of the same component. .NET should also detect incompatibility as soon as possible and alert the client.

  • Manage Custom Security Credentials the Smart (Client) Way

    Last updated: Wednesday, February 20, 2019

    Published in: CODE Magazine: 2005 - November/December

    Both Internet and intranet applications often require a custom store for user accounts and roles. ASP.NET 2.0 provides an out-of-the-box provider model as well as a SQL Sever database just for that propose. Unfortunately, the only way to administer the credentials databases is via Visual Studio 2005, and only for local Web applications. This article presents a full-blown custom security management application that administrators can use. The application wraps the ASP.NET 2.0 providers with a Web service and even adds missing features. This article presents the design approaches, challenges, and techniques involved in developing such an application. The article also walks you through some powerful yet useful techniques such as interface-based Web services, reflection-based Web service compatibility, advanced C# 2.0, Web services security, and Web services transactions.

  • Preparing for Indigo - Choosing the Right Technology Today

    Last updated: Tuesday, February 19, 2019

    Published in: CODE Magazine: 2005 - March/April

    Indigo is the next generation application connectivity and services from Microsoft, superseding the variety of .NET connectivity solutions available today: ASMX Web services, Remoting, and Enterprise Services. Since .NET debuted some five years ago, all three technologies have been inundated in either hype or misconceptions. With Indigo around the corner, it is time to take a long hard look at these three technologies, and separate fact from myth so that you will be best prepared for Indigo. This article starts by examining the existing technologies, describing their merits and shortcomings, putting them in the correct perspective of a modern distributed application, and suggests where to best apply them. Then the article briefly describes the Indigo programming model, and assesses how to best mitigate the cost of the migration.

  • Remote Object Models In .NET

    Last updated: Tuesday, February 19, 2019

    Published in: CODE Magazine: 2003 - January/February

    Modern applications are no longer isolated, stand-alone applications, limited to a single process or machine. Distributed applications allow you to put components in close proximity to the resources they use, allow multiple users to access the application, enable scalability and throughput, and increase overall availability and fault isolation. Component-oriented programming is especially geared towards distribution because it is all about breaking the application into a set of interacting components, which you can then distribute to different locations. .NET has a vast infrastructure supporting distributed applications and remote calls. This article focuses on just a single aspect of .NET remoting: the different object activation models available to a distributed application.

  • WCF Essentials-A Developer’s Primer

    Last updated: Tuesday, February 19, 2019

    Published in: CODE Magazine: 2006 - May/June

    Windows Communication Foundation (WCF) provides a run-time environment for your services, enabling you to expose CLR types as services and to consume services as CLR types.Although in theory you can build services without it, in practice, WCF significantly simplifies this task. WCF is Microsoft’s implementation of a set of industry standards defining service interactions, type conversion, marshaling, and various protocols’ management. Because of that, WCF provides interoperability between services, and it promotes productivity, including the essential off-the-shelf plumbing required by almost any application. This article describes the essential concepts and building blocks of WCF and its architecture, enabling you to build simple services. Future articles in this series will address specific aspects, such as transaction management and security.

  • What's New in .NET 2.0 for Assemblies and Versioning?

    Last updated: Tuesday, February 19, 2019

    Published in: CODE Magazine: 2005 - July/August

    The third release of the .NET Framework (version 2.0) introduces many changes and innovations not just in the application frameworks, but also in the essential mechanics of assemblies themselves.Microsoft strived to improve on a few limitations of the original assemblies model, as well as provide new features and capabilities in assemblies and in the tools used to build and manage them, predominantly Visual Studio 2005. These include application assembly reference, reference aliasing, friend assembly, better strong name protection, specific versioning, and targeting specific CPU architectures, and more. This article describes each such new feature, and when applicable, recommends best practices and guidelines.

  • What's New in Visual Studio .NET 1.1?

    Last updated: Thursday, February 21, 2019

    Published in: CODE Magazine: 2003 - March/April, VFP Conversion Papers

    Visual Studio .NET provides a new set of features designed to improve and enhance the development experience. Most of these changes have to do with user ergonomics and are typical of a minor release of a Visual Studio product. Only a few of the changes are related to the underlying platform. This article assumes you are familiar with Visual Studio .NET 1.0 and it presents only the new features of the IDE (Integrated Development Environment) of Visual Studio .NET 1.1, for both C# and Visual Basic .NET. J# is not discussed because it was not part of Visual Studio .NET 1.0. In the interest of space, some minor cosmetic changes (such as reorganization of the Start page) are not listed.

  • Working with .NET Threads

    Last updated: Tuesday, February 19, 2019

    Published in: CODE Magazine: 2003 - September/October

    The .NET class Thread defined in the System.Threading namespace represents a managed thread.The Thread class provides various methods and properties to control the managed thread. Unfortunately, there is a significant potential for abusing these mechanisms, and most developers may not even realize they are doing anything wrong. This article describes the dos and don'ts of the Thread class, and then presents a wrapper class that simplifies starting a thread, correctly terminates a thread, and offers a more consistent class interface than that of the raw Thread class.