Enterprise Library Test Guide - Willy .Net

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Enterprise Library Test Guide
Solution
The FormattedDatabaseTraceListener class is already thread safe, so there is no need
to lock the database trace listener. The solution is to set the IsThreadSafe property to
true in the FormattedTraceListenerBase class. This is the base class of the Formatted-
DatabaseTraceListener class. The following is the modified code.
public abstract class FormattedTraceListenerBase : TraceListener, IInstrumentationEventProvider
{
public override bool IsThreadSafe
{
get
{
return true;
}
}
}
Verification
Running the test case again after applying the preceding code verified that the database
trace listener was scalable.
Testing the Cryptography Application Block
The Cryptography Application Block was tested to determine the cost of reading a
symmetric key from a key file. To pass the test, the cost could be slightly more than
when using Enterprise Library version 1.1 or when using one of the symmetric algorithm
classes in the .NET Framework 2.0 System.Security.Cryptography namespace.
Test Case
To run the test case, a key file was first generated with the Enterprise Library Configuration
Console. The data protection scope could be either current user or local
machine. The test case called the application block’s KeyManager.Read method to
read the symmetric key.
Problems
The test case revealed two problems. The first problem was that reading the key from
the file for each request was an expensive I/O operation that caused poor performance.
The second problem was that to read keys from an input stream, the application
block used the .NET Framework FileStream class. It constructed FileStream
objects with read/write access to the file. When concurrent users tried to access the
file, the .NET framework threw a System.IO.IOException exception. The following
error message displayed:
The process cannot access the file because it is being used by another process.