How to Create Symbolic Links and Hard Links in Java?

Java file system provides both hard and symbolic links, which let us make references to files and directories. In this article, we will learn how to create symbolic links and hard links in Java.

• Soft Links or Symbolic Links: Symbolic links are names of files or directories. They may stretch across several file systems and serve as pointers to the original file or directory.
• Hard Links: Multiple directory entries pointing to the same disk are known as hard links. All files that reference the same will update in response to changes made to one file.

Program to Create Symbolic Link in Java

Below is the code implementation to create a symbolic link to the original file.

Java

// Java program to demonstrate the creation of Symbolic link
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

public class SymbolicLinkExample
{
    public static void main(String args[])
    {
        try {
            // specify the original file and the symbolic link path
            Path originalPath = Paths.get("original.txt");
            Path symbolicLinkPath = Paths.get("symbolic_link.txt");

            // create a symbolic link
            Files.createSymbolicLink(symbolicLinkPath, originalPath);

            System.out.println("Symbolic link created successfully.");
        } catch (IOException e)
        {
            e.printStackTrace();
        }
    }
}

Output

Symbolic link created successfully.

Explanation of the above Program:

• In the above program, it creates a symbolic link named symbolic_link.txt that points to the original file original.txt.
• The createSymbolicLink method is used to create the symbolic link.
• After that, the path to the original file and the path to the symbolic link to be created.
• If the symbolic link is created successfully, the output message will be printed.

Program to Create Hard Links in Java

Below is the code implementation to create hard link to the original file.

Java

// Java program to demonstrate the creation of hardlink
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

public class HardLinkExample
{
    public static void main(String args[])
    {
        try {
            // specify the original file and the hard link path
            Path originalPath = Paths.get("original.txt");
            Path hardLinkPath = Paths.get("hard_link.txt");

            // check if the original file exists
            if (!Files.exists(originalPath))
            {
                // if the original file does not exist, create it
                Files.createFile(originalPath);
                System.out.println("Original file created.");
            }

            // create a hard link
            Files.createLink(hardLinkPath, originalPath);

            System.out.println("Hard link created successfully.");
        } catch (IOException e) {
            System.out.println("Error creating hard link: " + e.getMessage());
        }
    }
}

Output

Original file created.
Hard link created successfully.

Explanation of the above program:

• In the above program, it first checks if the original file original.txt exists. If not, it creates it using Files.createFile.
• It then creates a hard link named hard_link.txt that points to the original file using Files.createLink.
• If the hard link created successfully, it will print the output message.