Exception Handling in Java

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Exception handling is a mechanism in Java that allows you to handle errors and exceptions that occur during program execution. When an exception occurs, the normal flow of execution is interrupted, and the control is transferred to the appropriate catch block to handle the exception.

In Java, exceptions are objects that are derived from the class Throwable. There are two types of exceptions in Java:

  1. Checked exceptions: These are the exceptions that are checked at compile-time, and the programmer is forced to handle these exceptions explicitly using try-catch blocks or declare them in the method signature using the throws keyword.

  2. Unchecked exceptions: These are the exceptions that are not checked at compile-time, and the programmer is not forced to handle these exceptions explicitly. These exceptions are subclasses of RuntimeException or Error.

To handle exceptions in Java, you need to use try-catch blocks. The try block contains the code that might throw an exception, and the catch block contains the code that handles the exception. Here is an example:

php
try {
   // code that might throw an exception
}
catch(Exception e) {
   // code to handle the exception
}

You can also have multiple catch blocks to handle different types of exceptions. The catch blocks are executed in the order they are defined, so you should define the catch blocks for the most specific exceptions first, followed by the catch block for more general exceptions. Here is an example:

scss
try {
   // code that might throw an exception
}
catch(ArithmeticException e) {
   // code to handle arithmetic exception
}
catch(IOException e) {
   // code to handle IO exception
}
catch(Exception e) {
   // code to handle all other exceptions
}

In addition to try-catch blocks, you can also use the finally block to specify code that should be executed regardless of whether an exception occurs or not. The finally block is often used to release resources, such as closing a file or database connection. Here is an example:

php

try { // code that might throw an exception } catch(Exception e) { // code to handle the exception } finally { // code that is always executed } 

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