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    <properties>
        <title>Log4j 2 Scala API</title>
        <author email="mikes@apache.org">Mikael Ståldal</author>
    </properties>

    <body>
        <section name="Log4j 2 API">
            <a name="ScalaAPI"/>
            <subsection name="Scala API">
                <p>
                    Log4j 2 has a companion Log4j Scala project that contains a convenient Scala wrapper for the
                    <a class="javadoc" href="../log4j-api/apidocs/org/apache/logging/log4j/Logger.html">Logger</a>
                    API.
                </p>

                <h4>Requirements</h4>
                <p>
                    Log4j 2 Scala API is dependent on the Log4j 2 API, Scala runtime library and reflection.
                    It currently supports Scala 2.10, 2.11, 2.12, 2.13. Scala 3 support has been recently added.
                    See <a href="../maven-artifacts.html#Scala_API">instructions</a>
                    on including this in an SBT, Maven, Ivy, or Gradle project.
                </p>

                <h4>Example</h4>
                <pre class="prettyprint linenums">
import org.apache.logging.log4j.scala.Logging
import org.apache.logging.log4j.Level

class MyClass extends BaseClass with Logging {
  def doStuff(): Unit = {
    logger.info("Doing stuff")
  }
  def doStuffWithLevel(level: Level): Unit = {
    logger(level, "Doing stuff with arbitrary level")
  }
}
                </pre>
                <p>
                    The output from the call to logger.info() will vary significantly depending on the configuration
                    used. See the
                    <a href="./configuration.html">Configuration</a>
                    section for more details.
                </p>
                <h4>Substituting Parameters</h4>
                <p>
                    Frequently the purpose of logging is to provide information about what is happening in the system,
                    which requires including information about the objects being manipulated. In Scala, you can use
                    <a href="https://docs.scala-lang.org/overviews/core/string-interpolation.html">string interpolation
                    </a>
                    to achieve this:
                </p>
                <pre class="prettyprint">
logger.debug(s"Logging in user ${user.getName} with birthday ${user.calcBirthday}")
                </pre>
                <p>
                    Since the Scala Logger is implemented with macros, the String construction and method invocations
                    will only occur when debug logging is enabled.
                </p>

                <h4>Logger Names</h4>
                <p>
                    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/Scala package names.
                    The Logging trait will automatically name the Logger accordingly to the class it is being used in.
                </p>

              <p>Please see the <a href="https://logging.apache.org/log4j/scala/index.html">Log4j Scala</a> project for more details.</p>

            </subsection>
        </section>
    </body>
</document>
