The try
, catch
, and finally
blocks are important components of the Java programming language. They are used to handle errors and exceptions in Java. The three blocks are used in the following way:
try
block is used to specify a block of code that may throw an exception. catch
block is used to handle the exception if it is thrown. finally
block is used to execute the code after the try
and catch
blocks have been executed.The following code snippet shows how to use these blocks:
public class Main {public static void main(String[] args) {try {// Code that may throw an exception} catch (Exception e) {// Code to handle the exception} finally {// Code that is always executed}}}
try
block contains the code that may throw an exception. If an exception is thrown in the try
block, the code in the catch
block is executed. catch
block contains the code that handles the Exception
. The order of the try
, catch
, and finally
blocks is important. If we place the finally
block before the catch
block, the code will not compile. finally
block contains the code that is always executed. The finally
block is executed even when an exception is not thrown. This is useful for cleanup code that must always be executed, such as closing a file.public class Main {public static void main(String[] args) {try {int arr[] = {1,2,3,4,5};// Code that may throw an exceptionSystem.out.println(arr[10]); // This statement will throw ArrayIndexOutOfBoundsException} catch (ArrayIndexOutOfBoundsException e) {// Code to handle ArrayIndexOutOfBoundsExceptionSystem.out.println("ArrayIndexOutOfBoundsException");} finally {// Code that is always executedSystem.out.println("finally block");}}}
ArrayIndexOutOfBoundsException
is thrown when trying to access an element of the array with an index that is out of bounds. The exception is caught by the catch
block.finally
block is executed afterward.The output of the code above will be:
ArrayIndexOutOfBoundsExceptionfinally block