There is little worse as a developer than trying to figure out why an application is not working if you don’t know what is going on inside it. Sometimes you can’t even tell whether the system is ...

# Logging is an importent part of code to catch errors or exceptions. Let's introduce logging to make our code debuggable. It's a good idea to creat a logfile. A logfile can be used for many purpose ...

# you may not use this file except in compliance with the License. # You may obtain a copy of the License at # http://www.apache.org/licenses/LICENSE-2.0 ...