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Java Java Objects (Retired) Delivering the MVP Validation

Albert Reel
Albert Reel
5,555 Points
Posted by Albert Reel
Albert Reel
5,555 Points

Delivering the MVP and stumped.

Can someone point me towards the source of my errors. I was trying to isolate the target char from the beginning of the input string and I keep running into syntax errors.

Anyone have a fresh look at this?

TeacherAssistant.java 
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 mFirstLetter = valueOf(fieldName.CharAt(0));
    char mSecondLetter = valueOf(fieldName.CharAt(1));

    while (mFirstLetter != 'm') {
      throw new IllegalArguementException ("Field must start with m");
    }

    while (! mSecondLetter.isUppercase) {
      throw new IllegalArguementException ("Please use CamelCase");
    }

    return fieldName;
  }

}

2 Answers

Stephen Bone
Stephen Bone
12,359 Points
Stephen Bone
Stephen Bone
12,359 Points

Hi Albert

There were a few issues mainly syntax errors. I've updated your code to reflect the changes and annotated it as best as I can remember ;)

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

    // removed the valueOf method as it was unnecessary
    // should be a lowercase 'c' for charAt method
    char mFirstLetter = fieldName.charAt(0);
    char mSecondLetter = fieldName.charAt(1);

    while (mFirstLetter != 'm') {
      // removed an 'e' in the spelling of argument
      throw new IllegalArgumentException ("Field must start with m");
    }
    // need to call the isUpperCase static method directly from the Character class
    // missing a capital 'C' in isUpperCase method
    while (! Character.isUpperCase(mSecondLetter)) {
      throw new IllegalArgumentException ("Please use CamelCase");
    }

    return fieldName;
  }

}

Hope it helps!

Stephen

Albert Reel
Albert Reel
5,555 Points
Albert Reel
Albert Reel
5,555 Points

Im embarrassed how many times I read over those mistakes. This makes a lot more sense. Thank you.

Stephen Bone
Stephen Bone
12,359 Points
Stephen Bone
Stephen Bone
12,359 Points

No worries, we all experience moments when we just can't see the error! Glad I could help.

Jess Sanders
Jess Sanders
12,086 Points
Jess Sanders
Jess Sanders
12,086 Points 
private char validateGuess(char letter) {
    if (!Character.isLetter(letter)) {
      throw new IllegalArgumentException("A letter is required."
    }
    letter = Character.toLowerCase(letter);
    if (mMisses.indexOf(letter) >= 0 || mHits.indexOf(letter) >= 0) { 
      throw new IllegalArgumentException(letter + " has already been guessed")           }
    return letter;
  }

  • The above code is the example to follow.

  • In pseudocode, we want to check for the following condition, and throw an error: " if the character at index 0 of fieldName does not equal 'm' OR the character at index 1 of fieldName is not upper case"

public class TeacherAssistant {

  public static String validatedFieldName(String fieldName) {
    if (fieldName.charAt(0) != 'm' || !Character.isUpperCase(fieldName.charAt(1))) {
      throw new IllegalArgumentException("The field name does not match the style");
    }
    return fieldName;
  }

}