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Yahya Saadi
4,277 PointsValidation
Trying to write a code to validate the field names. Please help
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 letter = 'm';
if (! Character.toLowerCase(letter)) {
throw new IllegalArgumentException("Member fields must start with an 'm'");
}
return fieldName;
}
}
1 Answer
Grigorij Schleifer
10,365 PointsHi Yahya,
sorry for the delay. Could you solve the challenge???
Here my suggestion how it could work:
public class TeacherAssistant {
public static String validatedFieldName(String fieldName) {
if(fieldName.charAt(0) != 'm') {
// the condition must be true to throw the exception
//so if at char 0 of fieldName the char is NOT 'm' the exception will be called
throw new IllegalArgumentException("No is required");
}
if(!Character.isUpperCase(fieldName.charAt(1))) {
// this is a little be tricky
// our String fieldName has no methods like isUpperCase ()
// so we need a class the has such fancy methods and accepts a char from our fieldName
// such classes are called WRAPPER classes
// here we use the Character class. Do you see the similarity between char and Character
// so we call the wrapper, then the isUpperCase method and pass the second char of the fieldName inside
}
return fieldName;
}
}
I hope the answer could help you
Grigorij