Advantages of Exception Handling in Java
Java provides a sophisticated exception handling mechanism that enables you to detect exceptional conditions in your programs and fix the exceptions as and when they occur. Using exception handling features offers several advantages. Let’s examine these advantages in detail.
Provision to Complete Program Execution:
One of the important purposes of exception handling in Java is to continue program execution after an exception is caught and handled.
The execution of a Java program does not terminate when an exception occurs. Once the exception is resolved, program execution continues till completion.
By using well-structured try, catch, and finally blocks, you can create programs that fix exceptions and continue execution as if there were no errors. If there is a possibility of more than one exception, you can use multiple catch blocks to handle the different exceptions.
The following program generates two random integers in each iteration of the for loop and performs a division operation. If a division by zero error occurs, the exception is handled in the catch block. Thus, an arithmetic exception does not terminate the program and the for loop continues execution after the catch block is executed.
import java.util.Random;
class ExceptionExample {
public static void main(String args[]) {
int a = 0, b = 0, c = 0;
Random r = new Random();
for (int i = 0; i < 10; i++) {
try {
b = r.nextInt();
c = r.nextInt();
a = 12345 / (b / c);
} catch (ArithmeticException e) {
System.out.println("Division by zero");
a = 0;
}
System.out.println("a: " + a);
}
}
}
Easy Identification of Program Code and Error-Handling Code:
The use of try/catch blocks segregates error-handling code and program code making it easier to identify the logical flow of a program. The logic in the program code does not include details of the actions to be performed when an exception occurs. Such details are present in the catch blocks.
Unlike many traditional programming languages that include confusing error reporting and error handling code in between the program code, Java allows you to create well-organized code. Separating error handling and program logic in this way makes it easier to understand and maintain programs in the long run.
Propagation of Errors:
Java’s exception handling mechanism works in such a way that error reports are propagated up the call stack. This is because whenever an exception occurs, Java’s runtime environment checks the call stack backwards to identify methods that can catch the exception.
When a program includes several calls between methods, propagation of exceptions up the call stack ensures that exceptions are caught by the right methods.
Meaningful Error Reporting:
The exceptions thrown in a Java program are objects of a class. Since the Throwable class overrides the toString() method, you can obtain a description of an exception in the form of a string and display the description using a println() statement.
catch (ArithmeticException e) {
System.out.println("Exception occurred: " + e);
}
The above catch statement displays the following output when an arithmetic exception occurs:
Exception: java.lang.ArithmeticException: / by zero
Traditional programming languages use error codes for error reporting. In the case of large programs, debugging errors using their error codes gets complex. The meaningful descriptions provided by Java’s exception handling mechanism are helpful when you need to debug large programs or experiment with complex code.
Identifying Error Types:
Java provides several super classes and sub classes that group exceptions based on their type. While the super classes like IOException provide functionality to handle exceptions of a general type, sub classes like FileNotFoundException provide functionality to handle specific exception types.
A method can catch and handle a specific exception type by using a sub class object.
For example, FileNotFoundException is a sub class that only handles a file not found exception. In case a method needs to handle multiple exceptions that are of the same group, you can specify an object of a super class in the method’s catch statement.
For example, IOException is a super class that handles all IO-related exceptions.
Happy Learning 🙂