content: /*
   * Copyright The OpenTelemetry Authors
   * SPDX-License-Identifier: Apache-2.0
   */
  
  package io.opentelemetry.javaagent.instrumentation.rabbitmq;
  
  import static io.opentelemetry.javaagent.extension.matcher.AgentElementMatchers.hasClassesNamed;
  import static io.opentelemetry.javaagent.extension.matcher.AgentElementMatchers.implementsInterface;
  import static io.opentelemetry.javaagent.instrumentation.rabbitmq.RabbitCommandInstrumentation.SpanHolder.CURRENT_RABBIT_CONTEXT;
  import static net.bytebuddy.matcher.ElementMatchers.isConstructor;
  import static net.bytebuddy.matcher.ElementMatchers.named;
  
  import com.rabbitmq.client.Command;
  import io.opentelemetry.context.Context;
  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 RabbitCommandInstrumentation implements TypeInstrumentation {
  
    @Override
    public ElementMatcher<ClassLoader> classLoaderOptimization() {
      return hasClassesNamed("com.rabbitmq.client.Command");
    }
  
    @Override
    public ElementMatcher<TypeDescription> typeMatcher() {
      return implementsInterface(named("com.rabbitmq.client.Command"));
    }
  
    @Override
    public void transform(TypeTransformer transformer) {
      transformer.applyAdviceToMethod(
          isConstructor(),
          RabbitCommandInstrumentation.class.getName() + "$CommandConstructorAdvice");
    }
  
    public static final class SpanHolder {
  
      public static final ThreadLocal<Context> CURRENT_RABBIT_CONTEXT = new ThreadLocal<>();
  
      private SpanHolder() {}
    }
  
    @SuppressWarnings("unused")
    public static class CommandConstructorAdvice {
  
      @Advice.OnMethodExit
      public static void setSpanNameAddHeaders(@Advice.This Command command) {
  
        Context context = CURRENT_RABBIT_CONTEXT.get();
        if (context != null && command.getMethod() != null) {
          RabbitInstrumenterHelper.onCommand(Java8BytecodeBridge.spanFromContext(context), command);
        }
      }
    }
  }
  