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Start your free trialmichael figueroa
5,680 Pointshow to test if second letter is uppercase
I'm not sure why my code continues to allow a lower case letter and a (_) to get through.
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 first = fieldName.charAt(0);
char second = fieldName.charAt(1);
boolean firstGood = Character.isLowerCase(first);
boolean secondGood = (!Character.isLowerCase(second));
boolean secondGoodChar = Character.isLetter(second);
if(!firstGood){
throw new IllegalArgumentException(first + " must be lower case.");
}
if(!secondGood && secondGoodChar ){
throw new IllegalArgumentException(second + "must be upper case");
}
return fieldName;
}
}
1 Answer
Simon Coates
28,694 Pointsit accepted the following:
public class TeacherAssistant {
public static String validatedFieldName(String fieldName) {
// These things should be verified:
// 1. Member fields must start with an 'm'
if(fieldName.charAt(0) != 'm'){
throw new IllegalArgumentException();
}
// 2. The second letter in the field name must be uppercased to ensure camel-casing
if(!Character.isUpperCase(fieldName.charAt(1))){
throw new IllegalArgumentException();
}
// NOTE: To check if something is not equal use the != symbol. eg: 3 != 4
return fieldName;
}
}
You don't seem to check for the 'm' being the first character.
Simon Coates
28,694 PointsSimon Coates
28,694 Points(!secondGood && secondGoodChar) will always evaluate to false when secondGoodChar is false. IE, no exception will occur if not a letter. (if i'm reading this right). You might want if(!(secondGood && secondGoodChar )){