### Question:
PathUtils { public static String base64Encode(byte[] bytes) { String hashString = Base64.getEncoder().encodeToString(bytes); return hashString; }  static String computeFileContentHash(Path path); static String base64Encode(byte[] bytes); static byte[] base64Decode(String data); static boolean isFileHidden(Path file); static Path getCommonPath(Path path1, Path path2);  }### Answer:
@Test public void testBase64Encode() { String content = "hello world"; String expected = "aGVsbG8gd29ybGQ="; String encoded = PathUtils.base64Encode(content.getBytes()); assertEquals(encoded, expected); }