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File I/O Classes Writing

File I/O Classes Writing


1. FileOutputStream:

   - Writes raw bytes to a file output stream.

   - Suitable for writing binary data to files.

   

   try (FileOutputStream fos = new FileOutputStream("output.txt")) {

       String data = "Hello, world!";

       byte[] bytes = data.getBytes();

       fos.write(bytes);

   } catch (IOException e) {

       e.printStackTrace();

   }


2. BufferedWriter:

   - Writes text to a character-output stream efficiently by buffering characters.

   

   try (BufferedWriter bw = new BufferedWriter(new FileWriter("output.txt"))) {

       String data = "Hello, world!";

       bw.write(data);

   } catch (IOException e) {

       e.printStackTrace();

   }


3. FileWriter:

   - Writes character files using the default character encoding.

   

   try (FileWriter fw = new FileWriter("output.txt")) {

       String data = "Hello, world!";

       fw.write(data);

   } catch (IOException e) {

       e.printStackTrace();

   }



4. PrintWriter:

   - Provides methods to write formatted text to a file.

   try (PrintWriter pw = new PrintWriter(new FileWriter("output.txt"))) {

       pw.println("Hello, world!");

   } catch (IOException e) {

       e.printStackTrace();

   }


5. DataOutputStream:

   - Writes primitive Java data types to an output stream in a portable way.

   try (DataOutputStream dos = new DataOutputStream(new FileOutputStream("output.dat"))) {

       dos.writeInt(42);

       dos.writeDouble(3.14);

   } catch (IOException e) {

       e.printStackTrace();

   }


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

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