in src/main/java/org/apache/commons/cli/OptionValidator.java [60:82]
static String validate(final String option) throws IllegalArgumentException {
// if opt is NULL do not check further
if (option == null) {
return null;
}
// handle the single character opt
if (option.length() == 1) {
final char ch = option.charAt(0);
if (!isValidOpt(ch)) {
throw new IllegalArgumentException("Illegal option name '" + ch + "'");
}
} else {
// handle the multi character opt
for (final char ch : option.toCharArray()) {
if (!isValidChar(ch)) {
throw new IllegalArgumentException("The option '" + option + "' contains an illegal " + "character : '" + ch + "'");
}
}
}
return option;
}