Home » Java programming language

Java DataOutputStream writeByte() Method with Example

DataOutputStream Class writeByte() method: Here, we are going to learn about the writeByte() method of DataOutputStream Class with its syntax and example.
Submitted by Preeti Jain, on March 30, 2020

DataOutputStream Class writeByte() method

• writeByte() method is available in java.io package.
• writeByte() method is used to write the given value as one-byte value to the basic stream and the variable counter is plus by 1 on successful execution.
• writeByte() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.
• writeByte() method may throw an exception at the time of writing byte.
  IOException: This exception may throw while getting any input/output error.

Syntax:

    public final void writeByte(int val);

Parameter(s):

• int val – represents the byte value to be written to the basic data output stream.

Return value:

The return type of the method is void, it returns nothing.

Example:

// Java program to demonstrate the example 
// of void writeByte(int val) method 
// of DataOutputStream

import java.io.*;

public class WriteByteOfDOS {
 public static void main(String[] args) throws Exception {
  ByteArrayOutputStream baos_stm = null;
  DataOutputStream dos_stm = null;

  byte[] b_arr = {
   10,
   20,
   30,
   40,
   50
  };

  try {
   // Instantiates ByteArrayOutputStream, DataOutputStream
   baos_stm = new ByteArrayOutputStream();
   dos_stm = new DataOutputStream(baos_stm);

   for (byte val: b_arr) {
    // By using writeByte() method isto write
    // byte value from the given byte array
    // to the dos_stm stream
    dos_stm.writeByte(val);
   }

   // By using flush() method isto
   // flush output bytes are written out
   // to the basic output stream
   dos_stm.flush();

   // By using toByArray() method isto
   // convert the stream baos_stm to byte 
   // array

   byte[] by = baos_stm.toByteArray();

   // Loop to display each byte to the
   // baos_stm data till its end

   for (byte val: by) {
    // Display byte
    System.out.println("dos_stm.writeByte(): " + val);
   }
  } catch (Exception ex) {
   System.out.println(ex.toString());
  } finally {
   // this block is to free all necessary system 
   // resources linked with the stream

   if (baos_stm != null)
    baos_stm.close();

   if (dos_stm != null)
    dos_stm.close();
  }
 }
}

Output

dos_stm.writeByte(): 10
dos_stm.writeByte(): 20
dos_stm.writeByte(): 30
dos_stm.writeByte(): 40
dos_stm.writeByte(): 50