On the .NET platform, the exception raised reads “System.Net.Sockets.SocketException: Only one usage of each socket address (protocol/network address/port) is normally permitted <host>:<port>“. 

In Java, the exception is “java.net.BindException: Address already in use: connect“. 

Both exceptions are misleading because they are generally associated with server socket conflicts – not outbound client socket connections.  However, a better understanding of the TCP state machine sheds some light on this behavior - and a solution.

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However, managing multiple threads and cross-thread communication adds complexity to your code.  Fortunately, the .NET Framework has a useful design pattern applied to its I/O classes which easily enables asynchronous calls.  Let’s take a look at an example.

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Developing software that uses SSL is an entirely different matter.  The simplicity quickly fades, and the developer must confront the complexities of certificate management, trust stores, handshaking, and a host of other details that must be perfectly aligned to make the secure communication work.  In Part 1, we’ll cover a very high level of SSL concepts.  In subsequent posts, we’ll take a deeper dive into making these connections happen in both Java and C#.

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To address this, PC manufacturers began adding fans dedicated to cooling this nerve center of the motherboard.  Today, with high end gaming machines consuming up to 1000W or more, enormous heat is generated not just by the CPU, but by the memory, north and south bridges, and the graphics card.  To expel this heat from inside the case, larger and faster case fans are needed to keep everything running at a safe, relatively cool temperature.

For the past few years, PC accessory vendors have been marketing liquid cooling systems.  These products promise to cool more efficiently, and more quietly, than traditional fans - at the same time adding several hundred dollars to the total price tag of a new machine.  The question is: is this just a pricey gimmick, or is this the next logical step in the progression of ever more powerful machines?

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One technology implemented by JAMES for spam filtering is real-time DNS blacklists.  DNSBLs identify the IP addresses of potential spam sources and machines known to be delivering spam (as determined by the sometimes controversial policies of the list owner).  Spam blacklists date back to 1996 with Paul Vixie’s Mail Abuse Prevention System, and are now used by ISPs and corporate mail systems around the world.  Countless organizations maintain blacklists, and Web sites like MX Toolbox permit ad hoc queries of IP addresses against dozens of published lists.

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This is a spectacular train wreck that had doom written all over it from Day One. It’s a familiar, predictable pattern constantly repeated since the first clueless manager commanded “just make it user friendly”.

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JUnit Factory is often able to generate mock instances automatically for problematic classes. When automocking fails, the developer can improve coverage by either extracting behaviors into private methods or by providing hints to JUnit Factory in the form of test data helpers.

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