Returns the numeric value of the character {@code ch} in the specified radix. <p> If the radix is not in the range {@code MIN_RADIX} ≤ {@code radix} ≤ {@code MAX_RADIX} or if the value of {@code ch} is not a valid digit in the specified radix, {@code -1} is returned. A character is a valid digit if at least one of the following is true: <ul> <li>The method {@code isDigit} is {@code true} of the character and the Unicode decimal digit value of the character (or its single-character decomposition) is less than the specified radix. In this case the decimal digit value is returned. <li>The character is one of the uppercase Latin letters {@code 'A'} through {@code 'Z'} and its code is less than {@code radix + 'A' - 10}. In this case, {@code ch - 'A' + 10} is returned. <li>The character is one of the lowercase Latin letters {@code 'a'} through {@code 'z'} and its code is less than {@code radix + 'a' - 10}. In this case, {@code ch - 'a' + 10} is returned. <li>The character is one of the fullwidth uppercase Latin letters A ({@code '\u005CuFF21'}) through Z ({@code '\u005CuFF3A'}) and its code is less than {@code radix + '\u005CuFF21' - 10}. In this case, {@code ch - '\u005CuFF21' + 10} is returned. <li>The character is one of the fullwidth lowercase Latin letters a ({@code '\u005CuFF41'}) through z ({@code '\u005CuFF5A'}) and its code is less than {@code radix + '\u005CuFF41' - 10}. In this case, {@code ch - '\u005CuFF41' + 10} is returned. </ul>