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Java Java Objects (Retired) Delivering the MVP Validation

Shane May
Shane May
5,114 Points
Posted by Shane May
Shane May
5,114 Points

How do I check if the first letter is a 'm' or if the second letter is capitol?

How do I check if the first letter is a 'm' or if the second letter is capitol?

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

    if(!fieldName.is){
     throw new IllegalArgumentException("Must begin with an m"); 
    }
    if(fieldName[1] != fieldName[1].toUpperCase()){
     throw new IllegalArgumentException("Second letter must be a capitol");   
    }
    return fieldName;
  }

}

1 Answer

Geovanie Alvarez
Geovanie Alvarez
21,500 Points
Geovanie Alvarez
Geovanie Alvarez
21,500 Points

This is a way that i did it

public class TeacherAssistant {

    public static String validatedFieldName(String fieldName) {
        // These things should be verified:
        // 1.  Member fields must start with an 'm'
        if (!fieldName.startsWith("m")) {
            throw new IllegalArgumentException("something"); // replace "something" with the message
        }

        // 2.  The second letter in the field name must be uppercased to ensure camel-casing
        if (!Character.isUpperCase(fieldName.charAt(1))) {
            throw new IllegalArgumentException("something"); // replace "something" with the message
        }

        // NOTE:  To check if something is not equal use the != symbol. eg: 3 != 4
        return fieldName;
    }

}
Shane May
Shane May
5,114 Points
Shane May
Shane May
5,114 Points

Thank you. I didn't know about the methods startsWith() and isUpperCase(). How did you know about those?