return JavaLetterOrDigit.INSTANCE;
  }

  /**
   * Determines whether a BMP character is upper case according to {@linkplain
   * Character#isUpperCase(char) Java's definition}.
   *
   * @deprecated Some uppercase characters are supplementary characters; see the class
   *     documentation.
   * @since 19.0 (since 1.0 as constant {@code JAVA_UPPER_CASE})
   */
  @Deprecated
  public static CharMatcher javaUpperCase() {

      .isEqualTo("http://%25:%25@host/%25?%25#%25")
    assertThat(url.resolve("").toString()).isEqualTo("http://%25:%25@host/%25?%25")
  }

  /**
   * Although HttpUrl prefers percent-encodings in uppercase, it should preserve the exact structure
   * of the original encoding.
   */
  @Test
  fun rawEncodingRetained() {
    val urlString = "http://%6d%6D:%6d%6D@host/%6d%6D?%6d%6D#%6d%6D"