Salesforce JavaScript Developer Practice Exam

What will happen when trying to invoke a static method on an instance of a class?

1. The method will execute successfully

2. A TypeError will occur

3. The instance will inherit the method

4. The method will return undefined

The correct answer is: A TypeError will occur

When invoking a static method on an instance of a class, a TypeError will be raised, indicating an issue with the context of the call. Static methods are designed to be called on the class itself, not on instances of the class. This design enforces that static methods belong to the class, allowing you to invoke them without requiring an instance. For example, if you define a static method within a class and attempt to call it through an instance, the JavaScript engine will not find the method in the context of the object, leading to an attempt to access a non-existent property on that instance. This results in a TypeError, reinforcing the primary purpose of static methods, which is to offer functionality associated with the class as a whole rather than with individual instances. In contrast, attempting to call an instance method through the class itself would be a different scenario. Static methods do not inherit from instances, nor do they return undefined when called inappropriately; their behavior is explicitly defined by their nature as class-level functions.