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Question: What is the purpose of the 'static' block in Java?
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Answer: The 'static' block in Java is a block of code enclosed within {} and preceded by the static keyword.
It is executed only once when the class is loaded into memory, typically used for static initialization of class-level variables.
The static block is useful over constructors when you do have to do some action even if no instances is still created.
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Question: Explain the 'try-with-resources' statement in Java?
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Answer: The 'try-with-resources' statement is used to automatically close resources such as streams,
files, or sockets after they are no longer needed.
It ensures that resources are closed properly, even if an exception occurs, by automatically invoking the close() method on the resources.
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Question: What is the purpose of the 'instanceof' operator in Java?
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Answer: The 'instanceof' operator is used to check whether an object is an instance of a particular class or interface.
It returns true if the object is an instance of the specified type or one of its subclasses, otherwise false.
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Question: What is the difference between an interface and an abstract class in Java?
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Answer: Please find the main difference below:
• An interface can only contain abstract methods and cannot have any method implementations, while an abstract class can have both abstract and concrete methods.
• A class can implement multiple interfaces but can extend only one abstract class.
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Question: What is the difference between final, finally, and finalize in Java?
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Answer: Please find the difference below:
• 'final' is a keyword used to declare constants, prevent method overriding, and make classes immutable.
• 'finally' is a block used in exception handling to ensure that a block of code is always executed, whether an exception is thrown or not.
• 'finalize()' is a method in the Object class that gets called by the garbage collector before an object is garbage collected.
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Question: What are lambda expressions in Java?
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Answer: In Java Lambda expressions are a concise way to represent anonymous functions, i.e., methods without a name.
They enable one to treat functionality as a method argument or pass code in a more compact form.
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Question: Can you explain the concept of method reference in Java?
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Answer: In Java Method reference is a shorthand syntax for invoking a method.
It allows you to reference a method without executing it, providing a concise way to pass methods as arguments to other methods or functional interfaces.
Method references provide a safe way to refer to the methods of Java classes and simplifies the process of maintaining code by offering
a shorthand syntax for calling previously defined procedures.
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