Log documentation

Log entry groups

The following groups of log entries are defined:
Low-level generic messagesorg.xins.common.lowlevel4
General I/Oorg.xins.common.io5
Service calling frameworkorg.xins.common.service10
Generic collection classesorg.xins.common.collections2
Expiry-related collection classesorg.xins.common.collections.expiry10
Servlet containerorg.xins.common.container15

Translation bundles

The following translation bundles are available:

Log levels

The following log levels can be used:

DEBUGDebugging messages. Only useful for programmers. This is the only level that may contain implementation details that are not exposed outside individual functions.
INFOInformational messages. Typically not important to operational people, except in cases where a problem is being traced or if behaviour is investigated.
NOTICEInformational messages that should typically be noticed by operational people.
WARNINGWarning messages. Should be noticed, but typically require no immediate action, although they may indicate a problem that should be fixed.
ERRORError messages. Indicates an error that should be fixed. However, it does not keep the whole application from functioning.
FATALFatal error messages. Indicates an error that keeps the whole application from functioning.

Note that it is a fatal condition to start with an unexpected condition of any crucial aspect of the application. If the configuration of all crucial aspects of the application could not be correctly and fully processed it is effectively in an unexpected state. Falling back to defaults does not imply returning to an expected condition because clearly some specific configuration was intended and expected.

This rule should be applied to determine whether a message should be logged at the FATAL level or not.