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Java DataOutputStream writeDouble() Method with Example

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

DataOutputStream Class writeDouble() method

• writeDouble() method is available in java.io package.
• writeDouble() method is used to write the given double value to the basic DataOutputStream.
• writeDouble() 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.
• writeDouble() method may throw an exception at the time of writing double.
  IOException: This exception may throw while getting any input/output error.

Syntax:

    public final void writeDouble(double val);

Parameter(s):

• double val – represents the double value to be written to the 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 writeDouble(double val) method 
// of DataOutputStream

import java.io.*;

public class WriteDoubleOfDOS {
 public static void main(String[] args) throws Exception {
  InputStream is_stm = null;
  DataInputStream dis_stm = null;
  FileOutputStream fos_stm = null;
  DataOutputStream dos_stm = null;

  double[] d = {
   10.0,
   20.0,
   30.0,
   40.0,
   50.0
  };

  try {
   // Instantiate FileInputStream, 
   // DataInputStream, FileOutputStream
   // and DataOutputStream 
   fos_stm = new FileOutputStream("C:\\Users\\Preeti Jain\\Desktop\\programs\\includehelp.txt");
   dos_stm = new DataOutputStream(fos_stm);
   is_stm = new FileInputStream("C:\\Users\\Preeti Jain\\Desktop\\programs\\includehelp.txt");
   dis_stm = new DataInputStream(is_stm);

   for (double val: d) {
    // By using writeDouble() method isto
    // write double value to the
    // DataOutputStream dos_stm
    dos_stm.writeDouble(val);
   }


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

   // Loop To Read Available Data till end
   while (dis_stm.available() > 0) {
    // By using readDouble() method isto read 
    // double from dis_stm
    double val = dis_stm.readDouble();
    System.out.println("dos_stm.writeDouble(val): " + val);
   }
  } catch (Exception ex) {
   System.out.println(ex.toString());
  } finally {
   // To free system resources linked
   // with these streams
   if (is_stm != null)
    is_stm.close();

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

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

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

Output

dos_stm.writeDouble(val): 10.0
dos_stm.writeDouble(val): 20.0
dos_stm.writeDouble(val): 30.0
dos_stm.writeDouble(val): 40.0
dos_stm.writeDouble(val): 50.0