Java.io.RandomAccessFile.readDouble() Method

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Description

The java.io.RandomAccessFile.readDouble() method reads a double from this file. This method reads a long value, starting at the current file pointer, as if by the readLong method and then converts that long to a double using the longBitsToDouble method in class Double.

Declaration

Following is the declaration for java.io.RandomAccessFile.readDouble() method

public final double readDouble()

Parameters

  • NA

Return Value

This method returns the next eight bytes of this file, interpreted as a double.

Exception

  • IOException -- if an I/O error occurs.Not thrown if end-of-file has been reached.

  • EOFException -- if this file reaches the end before reading eight bytes.

Example

The following example shows the usage of java.io.RandomAccessFile.readDouble() method.

package com.tutorialspoint;

import java.io.*;

public class RandomAccessFileDemo {

   public static void main(String[] args) {
      try {
         double d = 1.5987475;
         // create a new RandomAccessFile with filename test
         RandomAccessFile raf = new RandomAccessFile("c:/test.txt", "rw");

         // write something in the file
         raf.writeDouble(765.497634);

         // set the file pointer at 0 position
         raf.seek(0);

         // read double
         System.out.println("" + raf.readDouble());

         // set the file pointer at 0 position
         raf.seek(0);

         // write a double at the start
         raf.writeDouble(d);

         // set the file pointer at 0 position
         raf.seek(0);

         // read double
         System.out.println("" + raf.readDouble());
      } catch (IOException ex) {
         ex.printStackTrace();
      }

   }
}

Assuming we have a text file c:/test.txt, which has the following content. This file will be used as an input for our example program:

ABCDE  

Let us compile and run the above program, this will produce the following result:

765.497634
1.5987475



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