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Java Java Objects (Retired) Delivering the MVP Validation

If validatedFieldName() throws an exception, doesn't "throws <type>Exception" need to be in its signature?

In the exercise, the validatedFieldName() method will throw an IllegalArgumentException when the fieldName parameter doesn't begin with "m" followed by an uppercase letter. I thought that methods that throw exceptions must have a signature which includes a list of the exceptions thrown, e.g.

public void myMethod() throws IllegalArgumentException { //code if (<test>) { throw new IllegalArgumentException("Invalid parameter."); } }//myMethod()

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

Dan Johnson
Dan Johnson
40,533 Points

Since IllegalArgumentException is an unchecked exception (it extends RuntimeException) you're not required to add the throws clause or use a try-catch block.