content: /*
   * Copyright The OpenTelemetry Authors
   * SPDX-License-Identifier: Apache-2.0
   */
  
  package io.opentelemetry.javaagent.instrumentation.logback.mdc.v1_0;
  
  import static net.bytebuddy.matcher.ElementMatchers.isMethod;
  import static net.bytebuddy.matcher.ElementMatchers.isPublic;
  import static net.bytebuddy.matcher.ElementMatchers.named;
  import static net.bytebuddy.matcher.ElementMatchers.takesArgument;
  import static net.bytebuddy.matcher.ElementMatchers.takesArguments;
  
  import ch.qos.logback.classic.spi.ILoggingEvent;
  import io.opentelemetry.context.Context;
  import io.opentelemetry.instrumentation.api.util.VirtualField;
  import io.opentelemetry.javaagent.bootstrap.Java8BytecodeBridge;
  import io.opentelemetry.javaagent.extension.instrumentation.TypeInstrumentation;
  import io.opentelemetry.javaagent.extension.instrumentation.TypeTransformer;
  import net.bytebuddy.asm.Advice;
  import net.bytebuddy.description.type.TypeDescription;
  import net.bytebuddy.matcher.ElementMatcher;
  
  public class LoggerInstrumentation implements TypeInstrumentation {
  
    @Override
    public ElementMatcher<TypeDescription> typeMatcher() {
      return named("ch.qos.logback.classic.Logger");
    }
  
    @Override
    public void transform(TypeTransformer transformer) {
      transformer.applyAdviceToMethod(
          isMethod()
              .and(isPublic())
              .and(named("callAppenders"))
              .and(takesArguments(1))
              .and(takesArgument(0, named("ch.qos.logback.classic.spi.ILoggingEvent"))),
          LoggerInstrumentation.class.getName() + "$CallAppendersAdvice");
    }
  
    @SuppressWarnings("unused")
    public static class CallAppendersAdvice {
  
      @Advice.OnMethodEnter
      public static void onEnter(@Advice.Argument(value = 0, readOnly = false) ILoggingEvent event) {
        VirtualField.find(ILoggingEvent.class, Context.class)
            .set(event, Java8BytecodeBridge.currentContext());
      }
    }
  }
  