Exception handling is a powerful mechanism in Java that allows us to handle errors that occur during the execution of our program. This helps to ensure that our program does not crash and that the user receives a graceful error message.
What is an Exception in Java?
An exception in Java is an event that occurs during the execution of a program that disrupts the normal flow of instructions. Exceptions can be caused by a variety of factors, such as invalid input data, accessing a file that does not exist, or dividing by zero.
There are two main types of exceptions in Java:
- Checked exceptions: Checked exceptions are those that can be anticipated and handled by the programmer.
- Unchecked exceptions: Unchecked exceptions are those that cannot be anticipated and handled by the programmer.
When an exception occurs, the program will usually terminate abnormally. However, we can use exception handling to prevent this from happening. Exception handling allows us to gracefully handle exceptions and continue the execution of our program.
Common ways to handle exception in Java
The try-catch
block is the most common way to handle exceptions in Java. The try
block contains the code that we are trying to execute. If an exception occurs in the try
block, the catch
block will catch the exception and execute the code inside the catch
block.
The finally
block is executed after the try
block, regardless of whether an exception occurs. The finally
block is often used to close resources, such as files or sockets.
Following is an example of exception handling in Java:
try {
// Code that might throw an exception
} catch (Exception e) {
// Handle the exception
} finally {
// Close resources
}
In this example, the try
block contains the code that might throw an exception. If an exception occurs in the try
block, the catch
block will catch the exception and execute the code inside the catch
block. The finally
block will be executed regardless of whether an exception occurs.