content: /*
   * Copyright The OpenTelemetry Authors
   * SPDX-License-Identifier: Apache-2.0
   */
  
  package io.opentelemetry.javaagent.instrumentation.internal.logging;
  
  import static net.bytebuddy.matcher.ElementMatchers.named;
  import static net.bytebuddy.matcher.ElementMatchers.takesArguments;
  
  import io.opentelemetry.javaagent.bootstrap.logging.ApplicationLoggerFlags;
  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 LoggerFactoryInstrumentation implements TypeInstrumentation {
  
    @Override
    public ElementMatcher<TypeDescription> typeMatcher() {
      return named("org.slf4j.LoggerFactory");
    }
  
    @Override
    public void transform(TypeTransformer transformer) {
      // once a call to getILoggerFactory() exits we can be certain that slf4j is properly initialized
      transformer.applyAdviceToMethod(
          named("getILoggerFactory").and(takesArguments(0)),
          this.getClass().getName() + "$GetLoggerFactoryAdvice");
    }
  
    @SuppressWarnings("unused")
    public static class GetLoggerFactoryAdvice {
  
      @Advice.OnMethodExit(suppress = Throwable.class)
      public static void onExit() {
        if (ApplicationLoggerFlags.bridgeLoggerFactory()) {
          Slf4jApplicationLoggerBridge.install();
        }
      }
    }
  }
  