how to check if something has been written into file?

Question

I have a rather tricky question

Is there a way to check if something has been written into a file?

---

This is a piece of code written by Eric Petroelje, and I need to check if the "Hello world" has been written into a file.

This would be useful for checking if a big number is written to a text file. Thank you in advance!

public class Program {
    public static void main(String[] args) {
        String text = "Hello world";
        BufferedWriter output = null;
        try {
            File file = new File("example.txt");
            output = new BufferedWriter(new FileWriter(file));
            output.write(text);
        } catch ( IOException e ) {
            e.printStackTrace();
        } finally {
          if ( output != null ) {
            output.close();
          }
        }
    }
}

Answer 1

Read the file after having written it

public boolean writeToTXT(String text, String path)
{
    BufferedWriter output = null;
    try {
        File file = new File(path);
        output = new BufferedWriter(new FileWriter(file));
        output.write(text);
        output.flush();
        } catch ( IOException e ) {
            e.printStackTrace();
        } finally {
          if ( output != null ) {
            output.close();
          }
        }
        
    try(BufferedReader br = new BufferedReader(new FileReader(path))) {
    StringBuilder sb = new StringBuilder();
    String line = br.readLine();

    while (line != null) {
        sb.append(line);
        sb.append(System.lineSeparator());
        line = br.readLine();
    }
    return sb.toString().equals(text); }
}