The C++ API can output extensive information. This information can be useful in diagnosing connectivity issues or problems that you may encounter when writing the software that interfaces with the engine. As an author of a C++ client, you need not bother with the standard logging unless you want to modify its operating parameters.

By default, the log level is set to WARN, where only significant warnings and errors are displayed in the log. The whole list of log levels is OFF (that is, no logging at all), CRIT, FATAL, ERROR, WARN, INFO, DEBUG and TRACE. These levels are listed in order of decreasing importance, and conversely in the order of least likely occurrence. A very large volume of information is output at DEBUG level.

To change the logging, the C++ API provides various functions which can be found in the header file (.hpp). These functions generally have the term log in their names.

The logging facilities in Java and .NET are significantly more powerful than in C++. The Java API makes use of Log4j, a publicly available logging library for Java. For your convenience, Apama provides a wrapper class that abstracts the logging capabilities provided, and it is this interface that is used by the Client API for Java. See the Javadoc of the com.apama.util.Logger class for more information about the logging facility.

The .NET API makes use of log4net, a publicly available logging library for .NET. For your convenience, Apama provides a wrapper class that abstracts the logging capabilities provided, and it is this interface that is used by the Client API for .NET. See the documentation of the Apama.Util.Logger class for more information about the logging facility.