Log4j Format Specification

External

• http://logging.apache.org/log4j/2.x/manual/layouts.html

Internal

• log4j

Overview

log4j calls its output format layout. Most commonly used is the pattern layout.

Pattern Layout

http://logging.apache.org/log4j/2.x/manual/layouts.html#PatternLayout

The pattern layout is defined by a pattern string, where various element of a log event can be specified and the way they are intended to be displayed in a log file described. The format of the result depends on the conversion pattern, which is closely related to the conversion pattern of the printf function in C. The conversion pattern is composed of:

• literal text
• conversion specifiers

Literal Text

Literal text may include special characters (\t, \n \r \f).

Format Modifier

A format modifier modifies how the data generated by the pattern layout element