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What is the use of final keyword in Apex?
Apex constants are variables whose values don’t change after being initialized once. Constants can be defined using the final keyword. The final keyword means that the variable can be assigned at most once, either in the declaration itself, or with a static initializer method if the constant is defined in a class.
What does final do to a class?
The final modifier for finalizing the implementations of classes, methods, and variables. The main purpose of using a class being declared as final is to prevent the class from being subclassed. If a class is marked as final then no class can inherit any feature from the final class.
Why do we declare a method or class final?
You use the final keyword in a method declaration to indicate that the method cannot be overridden by subclasses. The Object class does this—a number of its methods are final .
Can final methods be overridden?
Can We Override a Final Method? No, the Methods that are declared as final cannot be Overridden or hidden. It is noteworthy that abstract methods cannot be declared as final because they aren’t complete and Overriding them is necessary.
Which method we Cannot be override?
No, we cannot override static methods because method overriding is based on dynamic binding at runtime and the static methods are bonded using static binding at compile time. So, we cannot override static methods. The calling of method depends upon the type of object that calls the static method.
Which is an example of an extended class in apex?
The following is an extended example of a class, showing all the features of Apex classes. The keywords and concepts introduced in the example are explained in more detail throughout this chapter. // Inner class – because it is virtual it can be extended.
How does a class implement an interface in apex?
To use an interface, another class must implement it by providing a body for all of the methods contained in the interface. Apex provides the keywords final, instanceof, super, this, transient, with sharing and without sharing.
What happens when a method is called in apex?
Depending on whether the method is called with one or two Integers, the Apex parser selects the appropriate implementation to execute. If the parser cannot find an exact match, it then seeks an approximate match using type coercion rules.
How is a variable defined in apex programming?
A variable, Method is defined with the static keyword is initialized once and associated with the class. Static variables, methods can be called by class name directly without creating the instance of a class. A constant, Method is defined with the final keyword can’t be overridden.