Question

Sorry for the lengthy code below, my code is able to execute and run properly when user input option ‘5’. I have already get all the values from user input and there is no error, but it did not write to my file.

My file currently has data in it:

Anthony Ducan;anthony;a123;55 Peter Street;3321444;VISA;3213504011223
Barry Blake;barry;a999;456 George Street;23239876;VISA;435677779876
Claire Rerg;clare;c678;925 Edward Lane;67893344;MASTERCARD;223344556677

I am trying to store the exact same way as my textfile.
Is there something wrong with my coding at void writeLinesToFile() method or is it the void newCust() method?

Still puzzled that I have no errors but it is not writing to my file.

public MainPage1(){ //start of MainPage1()

        System.out.println("=====================================================");
        System.out.println("Kreg Hotel Booking System - Main Page");
        System.out.println("=====================================================");
        System.out.println("[1] General Information");
        System.out.println("[2] Make Booking");
        System.out.println("[3] Active Booking Summary");
        System.out.println("[4] Existing Customer");
        System.out.println("[5] New Customer");
        System.out.println("[6] Check Booking Status");
        System.out.println("[7] Promotions");
        System.out.println("[8] Exit\n");
        System.out.println("Note: You have to select option 2 & 3 before option 4 & 5\n");
        System.out.println("Please enter your selection: ");        

try{choice = input.nextInt();}//to try to see if user input integer

         catch (java.util.InputMismatchException e){//to catch if user didnt input integer  
            System.out.println("Invalid Input");
            return;
        }


        while(true){ //start of do-while loop

            if(choice==4||choice==5)
            {
                if(roomInfo.isEmpty()==true || addOns.isEmpty()== true){
                    System.out.println("Please enter option 2 or 3 before option 4 or 5");
                    choice=input.nextInt();
                }
                else if(choice == 4){existingCustomers();}
                else if(choice ==5){newCust();}
                else new MainPage1();               
            }

        switch(choice){

                case 1:break;
                case 2:break;
                case 3:break;
                case 4:break;
                case 5:newCust();
                        break;
                case 6:break;
                case 7:break;
                case 8:System.out.println("Thank you. See you again soon");//exit the menu
                        System.exit(0);break;
                default:System.out.println("Please enter number between 1 to 8");//prompts the user if they didnt enter between 1 to 8
                       choice = input.nextInt();
                       break;
            }

        }//while(choice!=1 || choice !=2 || choice!=3 ||choice!=4); // end of do-while loop



    }//end of MainPage1()


public static void main(String[] args){//start of main page


    new MainPage1();//to call the constructor


}//end of mainpage



public void writeLinesToFile(String filename,String[] linesToWrite,boolean appendToFile){

    PrintWriter pw = null;

    try {

      if (appendToFile) {

        //If the file already exists, start writing at the end of it.
        pw = new PrintWriter(new FileWriter(filename, true));

      }
      else {

        pw = new PrintWriter(new FileWriter(filename));
        //this is equal to:
        //pw = new PrintWriter(new FileWriter(filename, false));

      }

      for (int i = 0; i < linesToWrite.length; i++) {

        pw.println(linesToWrite[i]+";");

      }
      pw.flush();

    }
    catch (IOException e) {
      e.printStackTrace();
    }
    finally {

      //Close the PrintWriter
      if (pw != null)
        pw.close();

    }

  }

  public void newCust(){

    System.out.println("Welcome to Kreg Hotel Booking System");
    System.out.println("==============================================");
    System.out.println("Please enter your name: ");
    n = input.nextLine();
    n = input.nextLine();
    System.out.println("Please enter your login username: ");
    un = input.nextLine();
    System.out.println("Please enter your login password: ");
    pw = input.nextLine();
    System.out.println("Please enter your address: ");
    a = input.nextLine();
    System.out.println("Please enter your contact: ");
    con = input.nextLine();
    System.out.println("Please enter your credit card type: ");
    ct = input.nextLine();
    System.out.println("Please enter your credit card number: ");
    cn = input.nextLine();
    MainPage1 util = new MainPage1();
     util.writeLinesToFile("customerinfo.txt",new String[]{n,un,pw,a,con,ct,cn},true);
     new MainPage1();

  }
}//end of class

Answer 1

Have a look at File, BufferedWriter and FileWriter docs. You should be able to accomplish this with those two class. This code should get you started.

String content = "Add this everytime";

File file =new File("example.txt");

//if file does not exists, then create it
if(!file.exists()){
   file.createNewFile();
}

//true = append file
FileWriter fileWritter = new FileWriter(file.getName(),true);
BufferedWriter bufferWritter = new BufferedWriter(fileWritter);
bufferWritter.write(content);
bufferWritter.close();

System.out.println("Done");