Tags: FileInputStream , FileOutputStream

This excerpt shows how you can copy content of source file to destination file using java.io.FileInputStream and java.io.FileOutputStream.

Source Code (Java 1.6 or less)

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

public class CopyFileExample {

    public static void main(String[] args) {
        /* Create object of File for source file */
        File sourceFile = new File("D:\\Readme.txt");
        /* Create object of File for destination file */
        File destinationFile = new File("D:\\CopyReadme.txt");

        /* Create object of FileInputStream */
        FileInputStream objFileInputStream = null;
        /* Create object of FileOutputStream */
        FileOutputStream objFileOutputStream = null;

        /* Check if source file is exists or not */
        if (sourceFile.exists()) {
            try {
                /* Obtain FileInputStream of source file */
                objFileInputStream = new FileInputStream(sourceFile);

                /* Create destination file if not exists */
                if (!destinationFile.exists()) {
                    destinationFile.createNewFile();
                }

                /* Obtain FileOutputStream of destination file */
                objFileOutputStream = new FileOutputStream(destinationFile);
                
                /* Read content from source File. */
                int byteOfData;
                while ((byteOfData = objFileInputStream.read()) != -1) {
                    /* Write content to destination File. */
                    objFileOutputStream.write(byteOfData);
                }
                System.out.println("File Copied!");
            } catch (FileNotFoundException ex) {
                ex.printStackTrace();
            } catch (IOException ex) {
                ex.printStackTrace();
            } finally {
                /* Close FileInputStream and FileOutputStream */
                try {
                    if (objFileInputStream != null) {
                        objFileInputStream.close();
                    }

                    if (objFileOutputStream != null) {
                        objFileOutputStream.close();
                    }
                } catch (IOException ex) {
                    ex.printStackTrace();
                }
            }
        } else {
            System.out.println("Source file not found!");
        }
    }
}

Source Code (Java 1.7 or above)(try-with-resources

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

public class CopyFileExample {

    public static void main(String[] args) {
        /* Create object of File for source file */
        File sourceFile = new File("D:\\Readme.txt");
        /* Create object of File for destination file */
        File destinationFile = new File("D:\\CopyReadme.txt");

        /* Check if source file is exists or not */
        if (sourceFile.exists()) {

            /* Create destination file if not exists */
            if (!destinationFile.exists()) {
                try {
                    destinationFile.createNewFile();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }

            try (
                    /* Create object of FileInputStream */
                    FileInputStream objFileInputStream = new FileInputStream(sourceFile);
                    /* Create object of FileOutputStream */
                    FileOutputStream objFileOutputStream = new FileOutputStream(destinationFile);
                ) {
                    /* Read content from source File. */
                    int byteOfData;
                    while ((byteOfData = objFileInputStream.read()) != -1) {
                        /* Write content to destination File. */
                        objFileOutputStream.write(byteOfData);
                    }
                    System.out.println("File Copied!");
            } catch (FileNotFoundException ex) {
                ex.printStackTrace();
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
    }
}

Other References:
What is try-with-resources in Java 7 or above?
How to read file in Java?
How to read file using FileInputStream in Java?
How to read/parse XML file in Java?
How to write file in Java?
How to append text to an existing file in Java?

Tags: FileInputStream , FileOutputStream