Home » Java programming language

Java FileInputStream finalize() Method with Example

FileInputStream Class finalize() method: Here, we are going to learn about the finalize() method of FileInputStream Class with its syntax and example.
Submitted by Preeti Jain, on April 01, 2020

FileInputStream Class finalize() method

• finalize() method is available in java.io package.
• finalize() method is used to assure that close() method of this FileInputStream invokes when there are none references exists or in other words, we can say close() method call after destroying or free all of its references.
• finalize() 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.
• finalize() method may throw an exception at the time of finalizing the stream.
  IOException: This exception may throw while getting any input/output error.

Syntax:

    protected void finalize();

Parameter(s):

• It does not accept any parameter.

Return value:

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

Example:

// Java program to demonstrate the example 
// of void finalize() method of FileInputStream

import java.io.*;

public class FinalizeOfFIS extends FileInputStream {
 public FinalizeOfFIS() throws Exception {
  super("D:\\includehelp.txt");
 }

 public static void main(String[] args) throws IOException {
  int val;
  try {
   // Instantiates FinalizeOfFIS
   FinalizeOfFIS fis_stm = new FinalizeOfFIS();

   // By using read() method is to read
   // a byte from fis_stm
   val = fis_stm.read();

   // Display corresponding bytes value
   byte b = (byte) val;

   // Display value of b
   System.out.println("fis_stm.read() before finalize(): " + b);

   // By using finalize() method is to free
   // memory when no more references exists   
   fis_stm.finalize();

   // when we call read() method after
   // finalizing the stream will not result an exception
   val = fis_stm.read();
   b = (byte) val;
   System.out.println("fis_stm.read() after finalize(): " + b);

  } catch (Exception ex) {
   System.out.println(ex.toString());
  }
 }
}

Output

fis_stm.read() before finalize(): 0
fis_stm.read() after finalize(): 4