code: @Override
  	public void writeLoaderClasses(String loaderJarResourceName) throws IOException {
  		URL loaderJar = getClass().getClassLoader().getResource(loaderJarResourceName);
  		try (JarInputStream inputStream = new JarInputStream(
  				new BufferedInputStream(loaderJar.openStream()))) {
  			JarEntry entry;
  			while ((entry = inputStream.getNextJarEntry()) != null) {
  				if (entry.getName().endsWith(".class")) {
  					writeEntry(new JarArchiveEntry(entry),
  							new InputStreamEntryWriter(inputStream, false));
  				}
  			}
  		}
  	}
docs: Write the required spring-boot-loader classes to the JAR.
  @param loaderJarResourceName the name of the resource containing the loader classes
  to be written
  @throws IOException if the classes cannot be written