Java Language
- Getting started with Java Language
- Top 10 Java Errors with Solutions
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Java Language log4j / log4j2
Introduction
Apache Log4j is a Java-based logging utility, it is one of several Java logging frameworks. This topic is to show how to setup and configure Log4j in Java with detailed examples on all of its possible aspects of usage.
Syntax
- Logger.debug("text to log"); // Logging debugging info
- Logger.info("text to log"); // Logging common info
- Logger.error("text to log"); // Logging error info
- Logger.warn("text to log"); // Logging warnings
- Logger.trace("text to log"); // Logging trace info
- Logger.fatal("text to log"); // Logging fatal errors
- Log4j2 usage with parameter logging:
- Logger.debug("Debug params {} {} {}", param1, param2, param3); // Logging debug with parameters
- Logger.info("Info params {} {} {}", param1, param2, param3); // Logging info with parameters
- Logger.error("Error params {} {} {}", param1, param2, param3); // Logging error with parameters
- Logger.warn("Warn params {} {} {}", param1, param2, param3); // Logging warnings with parameters
- Logger.trace("Trace params {} {} {}", param1, param2, param3); // Logging trace with parameters
- Logger.fatal("Fatal params {} {} {}", param1, param2, param3); // Logging fatal with parameters
- Logger.error("Caught Exception: ", ex ); // Logging exception with message and stacktrace (will automatically be appended)
Remarks
End of Life for Log4j 1 reached
On August 5, 2015 the Logging Services Project Management Committee announced that Log4j 1.x had reached end of life. For complete text of the announcement please see the Apache Blog. Users of Log4j 1 are recommended to upgrade to Apache Log4j 2.
log4j / log4j2 Related Examples
- Basic log4j2.xml configuration file
- Filter Logoutput by level (log4j 1.x)
- How to get Log4j
- How to use Log4j in Java code
- Migrating from log4j 1.x to 2.x
- Properties-File to log to DB
- Setting up property file
