Reading and Writing text File in Java

var regex = /^([a-zA-Z0-9])+([\w_\.\-]([a-zA-Z0-9])*[a-zA-Z0-9])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;

Simple code to demonstrate to Read and Write text file in Java.



package email;

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

public class ReadAndWriteFile {

public static void main(String[] args) {
  try {
    
   String content = "This is the content to write into file";
     
   File writeFile = new File("D:/Sample.txt");

   // if file doesnt exists, then create it
   if (!writeFile.exists()) {
    writeFile.createNewFile();
   }
/**
  * When we pass true as parameter to FilwWriter
  * then it appends the content in file instead of overwriting the content
  */
   //FileWriter fw = new FileWriter(file.getAbsoluteFile(),true);
   FileWriter fw = new FileWriter(writeFile.getAbsoluteFile());
   BufferedWriter bw = new BufferedWriter(fw);
   bw.write(content);
   bw.close();   
   fw.close();
  
   /**
    * File reading logic
    */
   File readFile = new File("D:/Sample.txt");
   BufferedReader bufferedReader = new BufferedReader(new FileReader(readFile));
  
   String line = "";
  
   while((line = bufferedReader.readLine()) != null)
   {
  System.out.println("Read from file===>"+line+"\n");
   }
   bufferedReader.close();
  } catch (IOException e) {
   e.printStackTrace();
  }
}
}