Question

So I have the following code where I should read a Text File (This is just the Main Class):

import gui.MenuWindow;
import java.io.IOException;
import javax.swing.JOptionPane;

public class Assessor {

    public static void main(String args[]) throws IOException {

        FileLoader file = new FileLoader("Example.txt");
        try{
            new MenuWindow(file.loader());
        } catch(Exception exc) {
            JOptionPane.showMessageDialog(null, "Error Reading File");
        }
    }
}

Then I’d have to load the Text into a ListBox using Swing. The thing is that I’ve found this new code to read a Text File:

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.FileNotFoundException;
import java.io.IOException;

public class ReadTextFileExample {
    public static void main(String[] args) {
        File file = new File("test.txt");
        StringBuffer contents = new StringBuffer();
        BufferedReader reader = null;

        try {
            reader = new BufferedReader(new FileReader(file));
            String text = null;

            // repeat until all lines is read
            while ((text = reader.readLine()) != null) {
                contents.append(text)
                    .append(System.getProperty(
                        "line.separator"));
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (reader != null) {
                    reader.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

        // show file contents here
        System.out.println(contents.toString());
    }
}

So I’d like to know what is the difference between the following two lines:

FileLoader file = new FileLoader("Example.txt"); //First Code

File file = new File("test.txt"); //Second Code

And… What’s the StringBuffer and BufferedReader used to? Thanks!

Answer 1

So I’d like to know what is the difference between the following two lines:

FileLoader file = new FileLoader("Example.txt"); //First Code

File file = new File("test.txt"); //Second Code

The first creates a java.io.FileLoader which Andreas discusses. Since the javadoc says "The constructors of this class assume that the default character encoding and the default byte-buffer size are appropriate", it should never be used.

The second creates a java.io.File which is just a file path with some utility methods that can be used to read directory trees, delete, create, and move files, etc., or it can be used with FileInputStream and other classes to actually access the file contents.

And… What’s the StringBuffer and BufferedReader used to? Thanks!

The StringBuffer is used to collect the contents of the file.

The BufferedReader is used to speed up reading of the file. Instead of reading one character at a time, the BufferedReader batches reads using an internal buffer.