1. What is a functional interface in Java 8? A functional interface has exactly one abstract method. It can have multiple default or static methods. Example: Runnable, Comparator, or custom: @FunctionalInterfaceinterface MyFunc { void execute(); } 2. What is a lambda expression? A lambda expression provides a concise way to represent an anonymous function. Example: […]
1. What is the difference between abstract classes and interfaces in Java? Abstract classes can have both abstract and concrete methods, while interfaces can only have abstract methods (until Java 8, which introduced default and static methods). A class can implement multiple interfaces but only extend one abstract class. 2. How does Java handle memory […]
1. What is the difference between final, finally, and finalize()? final is a keyword used to define constants, prevent method overriding, or inheritance. finally is a block that always executes after try-catch. finalize() is a method invoked by the garbage collector before object destruction (now deprecated). 2. How does Java achieve memory management? Java uses […]