Read a file with InputStream

Question

So I have a file that has one line of int : 5551212

I am trying to use InputStream to read this file and then see if I can extract the number written within in it

I did the following steps:

import java.io.*;

class Shuffle {


    public static void main(String args[]) throws IOException {
        FileInputStream newfile = new FileInputStream("file path");
        System.out.println(newfile.getChannel());
        System.out.println(newfile.getFD()); 
        System.out.println("Number of remaining bytes:"+newfile.available());
        int data;
        while ((data = newfile.read()) != -1) {
            System.out.print(data + " ");   
        }
        newfile.close();
    }  
}

However, the output that I got is: 53, 53, 53, 49, 50, 49, 50

I am not really sure what this is suppose to represent, or simply how do I use InputStream on integers

Answer 1

With Java 11 or above, a file can be read using a single line of code - Files.readString

Here is a working example for reading a text file:

// File name:  ReadFile.java

import java.nio.file.*;

public class ReadFile {

    public static void main(String[] args) throws Exception {
        String path = "my-file.txt";
        // Read file content as a string
        System.out.println(Files.readString(Paths.get(path)));
    }
}

Output:

> javac ReadFile.java

> java ReadFile
   5551212