Module 3

Exception Handling & File I/O in Java

25 mins read

Lesson 1: Exception Handling

1.1 Introduction to Exception Handling

Exception handling in Java provides a mechanism to manage runtime errors using try-catch-finally blocks, ensuring smooth program execution without crashing.

JAVA

// Example of try-catch block
try {
    int result = 10 / 0; // Division by zero
} catch (ArithmeticException e) {
    System.out.println("Error: Division by zero");
}

1.2 Checked vs Unchecked Exceptions

Checked exceptions are verified at compile-time (e.g. IOException), while unchecked exceptions occur at runtime (e.g. NullPointerException).

JAVA

// Checked exception handling
try {
    FileReader file = new FileReader("file.txt");
} catch (IOException e) {
    System.out.println("Error: File not found");
}

// Unchecked exception example
String str = null;
System.out.println(str.length()); // Throws NullPointerException

Module 2: OOP Principles Module 4: Data Structures