Here is an example of how you can use the BasicConfigurator class from the logback.classic package:

import ch.qos.logback.classic.LoggerContext;
import ch.qos.logback.classic.joran.JoranConfigurator;
import ch.qos.logback.classic.util.ContextInitializer;
import ch.qos.logback.core.joran.spi.JoranException;
import org.slf4j.LoggerFactory;

public class MyClass {
  public static void main(String[] args) {
    // Get the logger context
    LoggerContext context = (LoggerContext) LoggerFactory.getILoggerFactory();

    // Reset the context
    context.reset();

    // Configure the context using the BasicConfigurator
    BasicConfigurator.configure(context);

    // Alternatively, you can use the JoranConfigurator to load a configuration file
    try {
      JoranConfigurator configurator = new JoranConfigurator();
      configurator.setContext(context);
      context.reset();
      configurator.doConfigure("path/to/config.xml");
    } catch (JoranException je) {
      // StatusPrinter will handle this
    }
  }
}

The BasicConfigurator class is a utility class that provides a method for configuring a LoggerContext using a simple default configuration. The configure method takes a LoggerContext as an argument and sets up the context with a single console appender that outputs to System.out and a root logger with a level of DEBUG.

In this example, we use the configure method to configure the logger context using the default configuration. Alternatively, you can use the JoranConfigurator class to load a configuration from an XML file.