in src/main/java/org/apache/maven/shared/verifier/Embedded3xLauncher.java [127:144]
private static ClassLoader getBootLoader(String mavenHome, List<URL> classpath) {
List<URL> urls = classpath;
if (urls == null) {
urls = new ArrayList<>();
File bootDir = new File(mavenHome, "boot");
addUrls(urls, bootDir);
}
if (urls.isEmpty()) {
throw new IllegalArgumentException("Invalid Maven home directory " + mavenHome);
}
URL[] ucp = urls.toArray(new URL[0]);
return new URLClassLoader(ucp, ClassLoader.getSystemClassLoader().getParent());
}