Answers for "file reading and writing in java"

writing to a file in java

import java.io.FileWriter;   // Import the FileWriter class
import java.io.IOException;  // Import the IOException class to handle errors

public class WriteToFile {
  public static void main(String[] args) {
    try {
      FileWriter myWriter = new FileWriter("filename.txt");
      myWriter.write("Files in Java might be tricky, but it is fun enough!");
      myWriter.close();
      System.out.println("Successfully wrote to the file.");
    } catch (IOException e) {
      System.out.println("An error occurred.");
      e.printStackTrace();
    }
  }
}

How do you write or read data from or to file with Java?

Read data: I can use classes bufferedReader and bufferwriter. 
Lets say I have a text in Java.
I use bufferedReader to read the files if it is a random file 
bufferedReader is only the functionality to read a file.
For, Excel files I use the special library, Apache POI library. 
These are external libraries. 
I use properties class to read the properties files. 
Scanner class also for read the data from files