ImmutableList.Builder<URL> urls = ImmutableList.builder();
    for (String entry : Splitter.on(PATH_SEPARATOR.value()).split(JAVA_CLASS_PATH.value())) {
      try {
        try {
          urls.add(new File(entry).toURI().toURL());
        } catch (SecurityException e) { // File.toURI checks to see if the file is a directory
          urls.add(new URL("file", null, new File(entry).getAbsolutePath()));
        }
      } catch (MalformedURLException e) {

    ImmutableList.Builder<URL> urls = ImmutableList.builder();
    for (String entry : Splitter.on(PATH_SEPARATOR.value()).split(JAVA_CLASS_PATH.value())) {
      try {
        try {
          urls.add(new File(entry).toURI().toURL());
        } catch (SecurityException e) { // File.toURI checks to see if the file is a directory
          urls.add(new URL("file", null, new File(entry).getAbsolutePath()));
        }
      } catch (MalformedURLException e) {

    ImmutableList.Builder<URL> urls = ImmutableList.builder();
    for (String entry : Splitter.on(PATH_SEPARATOR.value()).split(JAVA_CLASS_PATH.value())) {
      try {
        try {
          urls.add(new File(entry).toURI().toURL());
        } catch (SecurityException e) { // File.toURI checks to see if the file is a directory
          urls.add(new URL("file", null, new File(entry).getAbsolutePath()));
        }

    assertThrows(IllegalArgumentException.class, () -> Resources.getResource(tempFile.getName()));

    // Now set the context loader to one that should find the resource.
    URL baseUrl = tempFile.getParentFile().toURI().toURL();
    URLClassLoader loader = new URLClassLoader(new URL[] {baseUrl});
    ClassLoader oldContextLoader = Thread.currentThread().getContextClassLoader();
    try {
      Thread.currentThread().setContextClassLoader(loader);

    ImmutableList.Builder<URL> urls = ImmutableList.builder();
    for (String entry : Splitter.on(PATH_SEPARATOR.value()).split(JAVA_CLASS_PATH.value())) {
      try {
        try {
          urls.add(new File(entry).toURI().toURL());
        } catch (SecurityException e) { // File.toURI checks to see if the file is a directory
          urls.add(new URL("file", null, new File(entry).getAbsolutePath()));
        }

    assertThrows(IllegalArgumentException.class, () -> Resources.getResource(tempFile.getName()));

    // Now set the context loader to one that should find the resource.
    URL baseUrl = tempFile.getParentFile().toURI().toURL();
    URLClassLoader loader = new URLClassLoader(new URL[] {baseUrl});
    ClassLoader oldContextLoader = Thread.currentThread().getContextClassLoader();
    try {
      Thread.currentThread().setContextClassLoader(loader);

     *
     * @param file the file (must not be {@literal null})
     * @return a URL object representing the file URL
     */
    public static URL toURL(final File file) {
        assertArgumentNotNull("file", file);

        try {
            return file.toURI().toURL();
        } catch (final IOException e) {
            throw new IORuntimeException(e);
        }
    }

    /**

    ImmutableList.Builder<URL> urls = ImmutableList.builder();
    for (String entry : Splitter.on(PATH_SEPARATOR.value()).split(JAVA_CLASS_PATH.value())) {
      try {
        try {
          urls.add(new File(entry).toURI().toURL());
        } catch (SecurityException e) { // File.toURI checks to see if the file is a directory
          urls.add(new URL("file", null, new File(entry).getAbsolutePath()));
        }

    ImmutableList.Builder<URL> urls = ImmutableList.builder();
    for (String entry : Splitter.on(PATH_SEPARATOR.value()).split(JAVA_CLASS_PATH.value())) {
      try {
        try {
          urls.add(new File(entry).toURI().toURL());
        } catch (SecurityException e) { // File.toURI checks to see if the file is a directory
          urls.add(new URL("file", null, new File(entry).getAbsolutePath()));
        }

     * c.g.c.io.Files.createTempDir?
     */
    File fullPath = new File(Files.createTempDir(), name);
    File jarFile = pickAnyJarFile();
    Files.copy(jarFile, fullPath);
    return fullPath.toURI().toURL();
  }

  private static File pickAnyJarFile() throws IOException {
    for (ClassPath.LocationInfo location :
        ClassPath.locationsFrom(ClassPathTest.class.getClassLoader())) {