content: /*
   * Copyright The OpenTelemetry Authors
   * SPDX-License-Identifier: Apache-2.0
   */
  
  package com.example.javaagent.instrumentation;
  
  import static io.opentelemetry.javaagent.extension.matcher.AgentElementMatchers.hasClassesNamed;
  import static java.util.Collections.singletonList;
  
  import com.google.auto.service.AutoService;
  import io.opentelemetry.javaagent.extension.instrumentation.InstrumentationModule;
  import io.opentelemetry.javaagent.extension.instrumentation.TypeInstrumentation;
  import java.util.List;
  import net.bytebuddy.matcher.ElementMatcher;
  
  /**
   * This is a demo instrumentation which hooks into servlet invocation and modifies the http
   * response.
   */
  @AutoService(InstrumentationModule.class)
  public final class DemoServlet3InstrumentationModule extends InstrumentationModule {
    public DemoServlet3InstrumentationModule() {
      super("servlet-demo", "servlet-3");
    }
  
    /*
    We want this instrumentation to be applied after the standard servlet instrumentation.
    The latter creates a server span around http request.
    This instrumentation needs access to that server span.
     */
    @Override
    public int order() {
      return 1;
    }
  
    @Override
    public ElementMatcher.Junction<ClassLoader> classLoaderMatcher() {
      return hasClassesNamed("javax.servlet.http.HttpServlet");
    }
  
    @Override
    public List<TypeInstrumentation> typeInstrumentations() {
      return singletonList(new DemoServlet3Instrumentation());
    }
  
    @Override
    public boolean isHelperClass(String className) {
      return className.startsWith("com.example.javaagent.instrumentation");
    }
  }
  