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Java Java Objects (Retired) Delivering the MVP Validation

check if uppercase

check if uppercase

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.charAt(0) != 'm' && !fieldName.charAt(1) ){
     throw new IllegalArgumentException("Fieldname must start with 'm' and must be uppercased!"); 
    }
    return fieldName;
  }

}

1 Answer

Kourosh Raeen
Kourosh Raeen
23,733 Points

You can use the isUpperCase() method from the Character class:

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.charAt(0) != 'm' || !Character.isUpperCase(fieldName.charAt(1))) {
      throw new IllegalArgumentException("Fieldname must start with 'm' and the second letter must be uppercased!");
    }
    return fieldName;
  }

}