docs: public static boolean loadAgent(URL agentJarURL) throws Exception {
          File toolsJarFile = findToolsJar();
          Class<?> vmClass = null;
  
          if (toolsJarFile == null || !toolsJarFile.exists()) {
              // likely Java 9+ (when tools.jar is not available).  Java
              // 9 also requires that
              // -Djvm.options=jdk.attach.allowAttachSelf=true is set.
              vmClass = ClassLoader.getSystemClassLoader().loadClass("com.sun.tools.attach.VirtualMachine");
          } else {
              vmClass = loadVirtualMachine(toolsJarFile);
          }
  
          if (vmClass == null) {
              return false;
          }
  
          attachAgent(vmClass, agentJarURL);
          return true;
      }