JAVA | Exception Handling | Introduction

2 Next Level Developer · Post JAVA | Exception Handling | Introduction Posting as Paritosh Agrawal Update Revert to draft Preview Close ComposeHTML Link
Introduction: An Exception is nothing but an exceptional or unexpected event that may occur during the program execution.

Examples:
  1. Invalid input: ValidationException
  2. File does not exist: FileNotFoundException
Exceptions are categorised into 3 categories.
    1. Checked exceptions
    2. Unchecked exceptions
    3. Errors
Checked exceptions: occurs at the compile time, also called as compile time exceptions. programmer is supposed to handle these exception.
Example: https://ideone.com/80B30I

Unchecked exceptions: occurs at the time of execution, also called as Runtime exceptions. Runtime Exception includes bugs, such as logic errors or improper use of an API.
Example: https://ideone.com/ZqWh7X

Java Exception Hierarchy: 



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