public static int toIntValue(Character ch) {
        if (ch == null) {
            throw new IllegalArgumentException("The character must not be null");
        }
        return toIntValue(ch.charValue());
    }
<p>Converts the character to the Integer it represents, throwing an
exception if the character is not numeric.</p>

<p>This method coverts the char '1' to the int 1 and so on.</p>

<pre>
  CharUtils.toIntValue('3')  = 3
  CharUtils.toIntValue(null) throws IllegalArgumentException
  CharUtils.toIntValue('A')  throws IllegalArgumentException
</pre>

@param ch  the character to convert, not null
@return the int value of the character
@throws IllegalArgumentException if the Character is not ASCII numeric or is null
android/android_framework/base/src/main/java/lang3/CharUtils.java