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Java Java Objects (Retired) Delivering the MVP Validation

Ernest Lin
Ernest Lin
2,691 Points
Posted by Ernest Lin
Ernest Lin
2,691 Points

How can check fieldName so it starts with m and the second letter capital?

How can check fieldName so it starts with m and the second letter capital?

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
    return fieldName;
  }

}

1 Answer

andren
andren
28,558 Points
andren
andren
28,558 Points

The simplest option would probably be something like this:

    if (fieldName.charAt(0) == 'm' && Character.isUpperCase(fieldName.charAt(1))) {
       return fieldName;
    } else {
       throw new IllegalArgumentException();
    }

charAt is a String method that allows you to get a char from a string at the given position, position 0 is the first letter, position 1 is the second letter, etc.

isUpperCase is a method of the Character class that returns true if the char you pass it is uppercase, and false if it is not.