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Java Java Objects (Retired) Delivering the MVP Validation

Posted by Gabriel E
Gabriel E
8,916 Points

How do I get the ThrowException to work?

Hi there,

I am having a might of trouble with this task. I am supposed to get some specific requirements to be passed, and if they don't pass as true, then I throw the Exception. I already received an answer earlier, and I altered my code to what I received in the response, but I'm getting 1 error: the =='m' is apparently not valid. If you could include some code, that would be great! Thanks for the help!

TeacherAssistant.java 
public class TeacherAssistant {

  public static String validatedFieldName(String fieldName) {
    fieldName.charAt(0) == 'm';
    Character.isUpperCase(fieldName.charAt(1));
  if(fieldName.charAt(0) == 'm' && Character.isUpperCase(fieldName.charAt(1))) {
     /// both things are true - do whatever success looks like
  }  else {
   throw new IllegalArgumentException("This does not meet the requirements!");


   //throw that exception
 }
    // 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
    return fieldName;
  }

}

3 Answers

Steve Hunter
Steve Hunter
57,712 Points

The answer you had was from me - I walked you through the code. If you're having trouble with that, it's probably best to flag that in the original post.

If you delete the first two lines you've added there so that the final code looks like:

public class TeacherAssistant {

public static String validatedFieldName(String fieldName) {

  if(fieldName.charAt(0) == 'm' && Character.isUpperCase(fieldName.charAt(1))) {
     // both things are true - do whatever success looks like
  } else {
     throw new IllegalArgumentException("This does not meet the requirements!");
  }
    return fieldName;
 }
}

That should be right. The other two lines were just me explaining what to do in the forum post.

I'll check, but I'm pretty sure the above will pass, else I'll be back to amend it!!

Steve.

Steve Hunter
Steve Hunter
57,712 Points

Confirmed to work. :-)

Gabriel E
Gabriel E
8,916 Points
Gabriel E
Gabriel E
8,916 Points

Thanks Steve, I'd like to say it worked, but when I pasted that exact code in, it says that the problem is something with =='m'. The little arrow carrot is pointing up at the 'm' in the fieldName.charAt method. I'm not sure what to do about this.

Steve Hunter
Steve Hunter
57,712 Points

Very odd ... did you remove the two lines of code that were not doing much - they looked like:

    fieldName.charAt(0) == 'm';
    Character.isUpperCase(fieldName.charAt(1));

The first line of your added code should start with the if.

If you jumped on my previous reply really quickly, you probably caught me mid-edit! So that may mean you pasted the wrong code in.

The code above does work. :-)

Steve.

Gabriel E
Gabriel E
8,916 Points
Gabriel E
Gabriel E
8,916 Points

Never mind, I got it. Thanks for your help!