how to change my file into binary data using java

To change a file into binary data using Java, you can read the contents of the file into a byte array using the readAllBytes method of the Files class, and then encode the byte array as a binary string using the Base64 class.

Here's an example of how you might do this:

import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.Base64;

public class Main {
    public static void main(String[] args) throws Exception {
        // Read the file into a byte array
        byte[] data = Files.readAllBytes(Paths.get("/path/to/file.txt"));

        // Encode the byte array as a binary string
        String binaryString = Base64.getEncoder().encodeToString(data);

        // Use the binary string
        // ...
    }
}

In this example, the readAllBytes method is used to read the contents of the file into a byte array, and the encodeToString method of the Base64 class is used to encode the byte array as a binary string.