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Noelle Acheson
610 PointsTrying to use isUpperCase
I'm trying to test for second character being uppercase - I get an error on the method, not sure why?
public class TeacherAssistant {
public static String validatedFieldName(String fieldName) {
// These things should be verified:
// 1. Member fields must start with an 'm'
// 2. The second letter in the field name must be uppercased to ensure camel-casing
// NOTE: To check if something is not equal use the != symbol. eg: 3 != 4
char firstChar = fieldName.charAt(0);
char secondChar = fieldName.charAt(1);
boolean secondTest = isUpperCase(secondChar);
if (firstChar != 'm' || secondTest) {
throw illegalArgumentException("The name does not match format");
}
return fieldName;
}
}
3 Answers
Sascha Bratton
3,671 PointsLooks like you've got a few problems here.
First, isUpperCase is a method of the Character class. So you need to call it like so:
boolean secondTest = Character.isUpperCase(secondChar);
Second, classes are case-sensitive, so illegalArgumentException needs to be IllegalArgumentException and also, you need to instantiate a new instance with new like so:
throw new IllegalArgumentException("The name does not match format");
And lastly, while that will take care of your compiler errors, the return on secondTest is going to be true if the second character of the fieldName parameter is, in fact, uppercase.
So in order to throw the exception if the second character is not uppercase, you need to make your condition to be if it is false, like so:
if (firstChar != 'm' || !secondTest) {
Nico Julian
23,657 PointsHi,
Since char is considered a primitive data type, it doesn't have methods attached to it. For this reason, there's a box type class, Character, which does contain methods. When you call isUpperCase(), try it like this:
boolean secondTest = Character.isUpperCase(secondChar);
if (firstChar != 'm' || !secondTest) {
throw new IllegalArgumentException("The name does not match format");
}
I added an '!' before second test since we want to throw the exception if the first character isn't 'm', or the second test isn't uppercase.
Noelle Acheson
610 PointsThanks!! I get it now!!!