Exception Handling (Hard)

Exception Handling in Java

• An exception in Java is an event that occurs during the execution of a program that disrupts the normal flow of instructions.
• The difference between an error and an exception in Java is that an error is a programming bug, while an exception is a runtime problem that can be handled by the program.

Try-Catch Block

• The try keyword is used to start a try block in Java.
• The catch keyword is used to catch and handle exceptions in Java.
• The finally block is used to specify a block of code that will always be executed, regardless of whether an exception is thrown or not.

Throwing Exceptions

• The throw keyword is used to explicitly throw an exception in Java.
• The throws keyword is used to specify that a method can throw an exception.
• Custom exceptions can be thrown using the throw keyword.

Purpose of Blocks

• The purpose of the try block is to enclose a set of statements that may throw an exception.
• The purpose of the catch block is to handle the exception thrown by the try block.
• The purpose of the finally block is to perform any necessary cleanup or finalization.

Multiple Catch Blocks

• A single try block can have multiple catch blocks.
• The syntax for declaring multiple catch blocks is catch (Exception1 e1) { } catch (Exception2 e2) { }.

Generic Catch Block

• A generic catch block is used to catch all types of exceptions.
• The purpose of a generic catch block is to handle any unexpected exceptions.

Types of Exceptions

• Checked exceptions arise during compilation time.
• Runtime exceptions arise during runtime.
• ArithmeticException is thrown when dividing a number by zero.

Handling Exceptions

• The purpose of exception handling in Java is to provide a way to handle runtime errors.
• If an exception occurs and there is no exception handler of the same type, the program will terminate.
• If an exception is not handled properly in Java, the program will crash.