套件： liblog4j1.2-java (1.2.17-9)

Logging library for java

log4j is a tool to help the programmer output log statements to a variety of output targets.

It is possible to enable logging at runtime without modifying the application binary. The log4j package is designed so that log statements can remain in shipped code without incurring a high performance cost.

One of the distinctive features of log4j is the notion of hierarchical loggers. Using loggers it is possible to selectively control which log statements are output at arbitrary granularity.

Log4j can output to: a file, a rolling file, a database with a JDBC driver, many output asynchronously, a JMS Topic, a swing based logging console, the NT event log, /dev/null, a SMTP server (using javamail), a socket server, syslog, telnet daemon and stdout.

The format of the output can be defined using one of the various layout (or user defined layout) like: simple text, html, date, pattern defined and XML.