Java Projects - Second Edition

Log frameworks

The most widely used logging framework is Apachelog4j. It currently has a second version that is a total rewrite of the first version. It is very versatile and has many appenders and formatters. The configuration of log4j can be in XML or the properties file format, and it can also be configured through API.

The author of log4j version 1 created a new logging framework—slf4j. This logging library is essentially a façade that can be used together with any other logging framework. Thus, when you use slf4j in a library you develop, and your code is added to a program as a dependency that uses a different logging framework, it is easy to configure slf4j to send the logs to the loggers of the other framework. Thus, the logs will ...