Java中Base64的几种用法小结

 /**
     * URL安全编码
     */
    @Test
    public void test1()
    {
        String input = RandomStringUtils.randomAlphanumeric(50);
        String encoded = Base64.getUrlEncoder().encodeToString(input.getBytes());
        log.info("{} --> {}", input, encoded);
        
        // 解码
        byte[] decodeBytes = Base64.getUrlDecoder().decode(encoded);
        log.info(new String(decodeBytes));
    }

 /**
     * 安全编码文件
     * 
     * @throws IOException
     */
    @Test
    public void testFile()
        throws IOException
    {
        byte[] fileBytes = Files.readAllBytes(Paths.get(new ClassPathResource("log4j2.xml").getURI()));
        String encoded = Base64.getUrlEncoder().encodeToString(fileBytes);
        log.info("Encoded file: {}", encoded);
        
        // 解码
        byte[] decodeBytes = Base64.getUrlDecoder().decode(encoded);
        log.info(new String(decodeBytes));
    }

 /**
     * 安全编码图片
     * 
     * @throws IOException
     */
    @Test
    public void testPic()
        throws IOException
    {
        // Paths相对路径为当前项目
        byte[] fileBytes = Files.readAllBytes(Paths.get("src/main/resources/data/18.jpg"));
        String encoded = Base64.getUrlEncoder().encodeToString(fileBytes);
        log.info("Encoded file: {}", encoded);
        
        // 解码
        byte[] decodeBytes = Base64.getUrlDecoder().decode(encoded);
        Files.write(Paths.get("/001.jpg"), decodeBytes);
    }

  /**
     * 安全编码图片
     * 
     * @throws IOException
     */
    @Test
    public void testNetPic()
        throws IOException
    {
        Resource resource = new UrlResource("https://i-blog.csdnimg.cn/direct/d4f0934d9ac041d583f81126fcc40f1d.png");
        try (InputStream is = resource.getInputStream())
        {
            // 编码解码网络图片
            String encoded = Base64.getUrlEncoder().encodeToString(IOUtils.toByteArray(is));
            byte[] decodeBytes = Base64.getUrlDecoder().decode(encoded);
            Files.write(Paths.get("/002.jpg"), decodeBytes);
        }
    }