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Java Java Objects (Retired) Delivering the MVP Validation

Victor Leschly Ørnby
PLUS
Victor Leschly Ørnby
Courses Plus Student 2,992 Points

Figuring out, checking uppercase on string without using isUpperCase char method

The header explains my problem

TeacherAssistant.java
public class TeacherAssistant {

  public static String validatedFieldName(String fieldName) {

    if(!fieldName.startsWith("m")) {
      throw new IllegalArgumentException("hej");
    }
    if() {
      throw new IllegalArgumentException("Is uppercase");
    }

    // 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

George Pirchalaishvili
George Pirchalaishvili
3,747 Points

Well you can use something like this, but I do not understand why dont you just use isUppercase.

I would just make char Array out of string and than manipulate with them.

public class TeacherAssistant {

  public static String validatedFieldName(String fieldName) {

    if(fieldName.charAt(0) != 'm') {
      throw new IllegalArgumentException("hej");
    }
    if(fieldName.charAt(1)=='_' || fieldName.toUpperCase().charAt(1) != fieldName.charAt(1)) {
      throw new IllegalArgumentException("Is uppercase");
    }

    // 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;
  }

}