Java Convert File to Byte Array

Tags: Byte Array

In this Java tutorial we learn how to read a file to a byte[] array in Java programming language.

How to convert a File to byte[] array in Java

In Java we can use Files.readAllBytes() method to read all content of a file into byte[] array. 

String fileName = "D:\\SimpleSolution\\data.txt";
Path filePath = Paths.get(fileName);
byte[] allBytes = Files.readAllBytes(filePath);

In the following Java example code we show you how to convert the file content into byte[] array in a Java application.

FileToByteArrayExample1.java 

import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

public class FileToByteArrayExample1 {
    public static void main(String... args) throws IOException {
        String fileName = "D:\\SimpleSolution\\data.txt";

        Path filePath = Paths.get(fileName);
        byte[] allBytes = Files.readAllBytes(filePath);

        System.out.println("File Bytes:");
        for(byte b : allBytes) {
            System.out.print(b);
        }

        String fileContent = new String(allBytes, StandardCharsets.UTF_8);
        System.out.println("\nFile Content:");
        System.out.println(fileContent);
    }
}
The output as below. 
File Bytes:
831051091121081013283111108117116105111110
File Content:
Simple Solution

Happy Coding 😊

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