FileHandlingActivity.java

import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

public class FileHandlingActivity {

    public static void debugFileOperation() {
        try {
            // Creating a file with an invalid name (forward slash is invalid for file names on many OS)
            File file = new File("fileName.txt");
            
            // Attempting to write to the invalid file
            FileWriter writer = new FileWriter(file);
            writer.write("Will this fail?");
            writer.close();
        } catch (IOException e) {
            System.out.println("An error occurred: " + e.getMessage());
            e.printStackTrace(); 
        }
    }
    public static void main(String[] args) {
        // Your code here

        // a. Create main directory
        File directory = new File("JavaFileSystem");
        directory.mkdir();

        // b. Create three text files

        // "notes.txt, data.txt, log.txt"
        File notes = new File(directory, "notes.txt");
        File data = new File(directory, "data.txt");
        File log = new File(directory, "log.txt");

        try {
            // c. Write messages to files
            FileWriter notesWriter = new FileWriter(notes);
            notesWriter
                    .write("These are my class notes for compsci. As u can see, they are empty.");
            FileWriter dataWriter = new FileWriter(data);
            dataWriter.write("Name: Matthew\nGrade: 12\nSSN:-1\nDOB: 3/17/2008");
            FileWriter logWriter = new FileWriter(log);
            logWriter.write("log(3)=3log(1)");
            notesWriter.close();
            dataWriter.close();
            logWriter.close();

            // d. Read and display file contents

            FileReader notesReader = new FileReader(notes);
            String notesStr = "";
            while (notesReader.ready()) {
                notesStr += (char) notesReader.read();
            }
            System.out.println(notesStr);

            FileReader dataReader = new FileReader(data);
            String dataStr = "";
            while (dataReader.ready()) {
                dataStr += (char) dataReader.read();
            }
            System.out.println(dataStr);

            FileReader logReader = new FileReader(log);
            String logStr = "";
            while (logReader.ready()) {
                logStr += (char) logReader.read();
            }
            System.out.println(logStr);

            // e. Create backup directory
            File backup = new File(directory, "Backup");
            backup.mkdir();

            // f. Copy contents to backup file
            File newNotes = new File(backup, "notes.txt");
            File newData = new File(backup, "data.txt");
            File newLog = new File(backup, "log.txt");
            FileWriter notesWriter2 = new FileWriter(newNotes);
            notesWriter2.write(notesStr);
            FileWriter dataWriter2 = new FileWriter(newData);
            dataWriter2.write(dataStr);
            FileWriter logWriter2 = new FileWriter(newLog);
            logWriter2.write(logStr);
            notesWriter2.close();
            dataWriter2.close();
            logWriter2.close();

            // g. List all files in both directories
            File[] files1 = directory.listFiles();
            File[] files2 = backup.listFiles();
            for (int i = 0; i < files1.length; i++) {
                System.out.println(files1[i]);
            }
            for (int i = 0; i < files2.length; i++) {
                System.out.println(files2[i]);
            }

        } catch (IOException e) {
            System.out.println("gng u a bum for that");
        }


        debugFileOperation();


    }
}