## JDK Logging Adapter The JDK Logging Adapter is a custom implementation of java.util.logging.LogManager that uses Log4j. This adapter can be used with either the Log4j API or Log4j Core. When used with the API, there are a couple features of JUL that aren't supported. However, this does allow any other Log4j Provider besides the Core provider to be used with JUL. ## Requirements The JDK Logging Adapter requires at least Java 6 and is dependent on the Log4j API and optionally Log4j Core. ## Usage To use the JDK Logging Adapter, you must set the system property `java.util.logging.manager` to org.apache.logging.log4j.jul.LogManager This must be done either through the command line (i.e., using the `-Djava.util.logging.manager=org.apache.logging.log4j.jul.LogManager` argument) or by using `System.setProperty()` before any calls are made to `LogManager` or `Logger`. ## Compatibility The use of a java.util.logging.Filter is supported on a per-Logger basis. However, it is recommended to use the standard Filters feature in Log4j instead. The use of java.util.logging.Handler classes is NOT supported. Custom Handlers should instead use an appropriate Appender or code their own Appender plugin. Java logging levels are translated into Log4j logging levels dynamically. The following table lists the conversions between a Java logging level and its equivalent Log4j level. Custom levels should be implemented as an implementation of LevelConverter, and the Log4j property `log4j.jul.levelConverter` must be set to your custom class name. Using the default `LevelConverter` implementation, custom logging levels are mapped to whatever the current level of the `Logger` being logged to is using.
Default Level conversions
Java Level | Log4j Level
--- | ---
OFF | OFF
SEVERE | ERROR
WARNING | WARN
INFO | INFO
CONFIG | CONFIG
FINE | DEBUG
FINER | TRACE
FINEST | FINEST
ALL | ALL