Public static Logger logger = LogManager.getFormatterLogger('Foo'); logger.debug('Logging in user%s with birthday%s', user.getName, user.getBirthdayCalendar); logger.debug('Logging in user%1$s with birthday%2$tm%2$te,%2$tY', user.getName, user.getBirthdayCalendar); logger.debug('Integer.MAXVALUE =%,d', Integer.MAXVALUE); logger.debug('Long.MAXVALUE =%,d', Long.MAXVALUE); To use a formatter Logger, you must call one of the LogManager methods. The output for this example shows that Calendar toString is verbose compared to custom formatting. Logger Names Most logging implementations use a hierarchical scheme for matching logger names with logging configuration.
In this scheme, the logger name hierarchy is represented by '.' Characters in the logger name, in a fashion very similar to the hierarchy used for Java package names. For example, org.apache.logging.appender and org.apache.logging.filter both have org.apache.logging as their parent. In most cases, applications name their loggers by passing the current class's name to LogManager.getLogger(.). Because this usage is so common, Log4j 2 provides that as the default when the logger name parameter is either omitted or is null.
For example, in all examples below the Logger will have a name of 'org.apache.test.MyTest'.
Logger in Java. Java Logging API was introduced in 1.4 and you can use java logging API to log application messages. In this java logging tutorial, we will learn basic features of Java Logger.
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Top Java Core and Java EE. Top Spring and Hibernate. Interview Questions. Certifications. Testing. Hot & New: j is a very popular logging library for Java development.
It provides convenient and flexible logging mechanism as well as fast performance.Putting log4j into your code is pretty easy as it requires minimum of work which mostly involves in configuring the logging system. This article describes the configuration of log4j in details, as well as providing some working examples. Table of content. 4. Steps to plug log4j into your codeTypically, the steps to use log4j in your Java application are as follows:. Download latest log4j distribution. Add log4j’s jar library into your program’s classpath.
Create log4j’s configuration. Initialize log4j with the configuration. Create a logger. Put logging statements into your code. Download log4jYou can get a distribution of log4j at: The latest version of log4j is 1.2.17. Download log4j-1.2.17.zip file and extract the archive into a directory you like.
The distribution comes with a lot of stuff: documentation, source code, examples but the only thing we need is the log4j-1.2.17.jar file – log4j’s JAR library.Add the log4j-1.2.17.jar into compilation classpath and runtime classpath of your project in order to have your code can be compiled and executed with log4j.