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Java Exception Handling MCQ Test

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File I/O Classes Reading

File I/O Classes Reading 


1. File Class:

   - Represents a file or directory path in the file system.

   - Provides methods for file manipulation and querying file attributes.

   


   File file = new File("example.txt");

   if (file.exists()) {

       System.out.println("File exists!");

   } else {

       System.out.println("File does not exist!");

   }



2. FileInputStream:

   - Reads raw bytes from a file input stream.

   - Suitable for reading binary data from files.

   


   try (FileInputStream fis = new FileInputStream("example.txt")) {

       int byteRead;

       while ((byteRead = fis.read()) != -1) {

           System.out.print((char) byteRead);

       }

   } catch (IOException e) {

       e.printStackTrace();

   }



3. BufferedReader:

   - Reads text from a character-input stream efficiently by buffering characters.

   


   try (BufferedReader br = new BufferedReader(new FileReader("example.txt"))) {

       String line;

       while ((line = br.readLine()) != null) {

           System.out.println(line);

       }

   } catch (IOException e) {

       e.printStackTrace();

   }



4. FileReader:

   - Reads character files using the default character encoding.

   


   try (FileReader fr = new FileReader("example.txt")) {

       int character;

       while ((character = fr.read()) != -1) {

           System.out.print((char) character);

       }

   } catch (IOException e) {

       e.printStackTrace();

   }



5. Scanner:

   - Parses primitive types and strings from the input stream.

   - Simplifies the process of reading user input or file contents.

   


   try (Scanner scanner = new Scanner(new File("example.txt"))) {

       while (scanner.hasNextLine()) {

           System.out.println(scanner.nextLine());

       }

   } catch (FileNotFoundException e) {

       e.printStackTrace();

   }



These examples demonstrate how to use various file I/O classes to read data from files in Java.

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