Logging, Konfiguration
Zum Logging auf Log-Files und zur Konfiguration sollten Singletons verwendet werden.

Beachten Multithreading-Problematik
   Logging: kann zum Bremsen des Servers führen
   Konfiguration: auf Seiteneffekte achten

Logging über log-Methoden des Servers

log(String) - Method in interface javax.servlet.ServletContext
   Writes the specified message to a servlet log file, usually an event log.
log(String) - Method in class javax.servlet.GenericServlet
   Writes the specified message to a servlet log file, prepended by the servlet's name.
log(String, Throwable) - Method in interface javax.servlet.ServletContext
   Writes an explanatory message and a stack trace for a given Throwable exception to the servlet log file.
log(String, Throwable) - Method in class javax.servlet.GenericServlet
   Writes an explanatory message and a stack trace for a given Throwable exception to the servlet log file, prepended by the servlet's name.

System.out.println() sollte nicht verwendet werden.

Konfiguration

Möglich über Properties-Files
Einlesen Initialization-Parameter aus web.xml
Verwendung von Resourcebundles
Internationalisierung über application-Parameter in web.xml

   <init-param>
      <param-name>application</param-name>
      <param-value>package.ApplicationResources</param-value>
   </init-param>