Java Program: File reading method with exception handling

Last update on March 11 2025 13:51:05 (UTC/GMT +8 hours)

File Not Found Exception

Write a Java program to create a method that reads a file and throws an exception if the file is not found.

Sample Solution:

Java Code:

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;

public class File_Read {
  public static void main(String[] args) {
    try {
      readFile("test1.txt");
    } catch (FileNotFoundException e) {
      System.out.println("Error: " + e.getMessage());
    }
  }

  public static void readFile(String fileName) throws FileNotFoundException {
    File file = new File(fileName);
    Scanner scanner = new Scanner(file);

    // Read and process the contents of the file
    while (scanner.hasNextLine()) {
      String line = scanner.nextLine();
      System.out.println(line);
    }

    scanner.close();
  }
}

Sample Output:

Error: test1.txt (The system cannot find the file specified)

Explanation:

In the above exercise,

• In this program, we have a method called readFile that takes a fileName parameter. To read the contents of the file, it creates a Scanner object using the File class.
• In the main method, we call the readFile method and provide the name of the file we want to read. If the file is not found, a FileNotFoundException is thrown.
• In the readFile method, we declare a File object and initialize it with the given fileName. We then create a Scanner object using the file. If the file is not found, a FileNotFoundException is thrown.
• A try-catch block is used in the main method to catch the FileNotFoundException and print an error message.

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Java program to attempt to read a file from a given path and throw a FileNotFoundException if it does not exist, then handle it gracefully.
• Write a Java program to throw a custom ConfigurationFileNotFoundException when a required configuration file is missing.
• Write a Java program to check the file extension of an input file and throw an exception if it is not ".txt".
• Write a Java program to open a file for reading and throw an exception if the file cannot be accessed due to insufficient permissions.

Java Code Editor:

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