Logging and aggregation are crucial tools for today's complex, distributed systems. They provide rich insights which keep time to recover short. We must therefore make sure we test logging adequately.
James Turnbull makes a compelling case for using Logstash for centralizing logging by explaining the implementation details of Logstash within the context of a logging project. The book targets both small companies and large enterprises through a two sided case; both for the low barrier to entry and the scaling capabilities.
In this InfoQ article, Boris Lublinsky highlights the problems with exception handling in SOA, and suggests applying SOA principles to exception handling as a solution. 7
Using logging seams you can easily create unobtrusive unit tests around legacy classes, without needing to edit class logic as well as avoiding behavior changes. 3