import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.util.NoSuchElementException;
import java.util.Scanner;

public class CreateSequentialFile {
	private ObjectOutputStream output; 

	// allow user to specify file name
	public void openFile() {
		try { // open file  
			output = new ObjectOutputStream(new FileOutputStream( "clients.ser" ));
		} 
		catch ( IOException ioException ) {
			System.err.println( "Error opening file." );
		} 
	}

	// add records to file
	public void addRecords() {
		AccountRecord record; // object to be written to file
		int accountNumber = 0; // account number for record object
		String firstName; // first name for record object
		String lastName; // last name for record object
		double balance; // balance for record object

		Scanner input = new Scanner( System.in );

		System.out.printf( "%s\n%s\n%s\n%s\n\n",
         "To terminate input, type the end-of-file indicator ",
         "when you are prompted to enter input.",
         "On UNIX/Linux/Mac OS X type <ctrl> d then press Enter",
         "On Windows type <ctrl> z then press Enter" );

		System.out.printf( "%s\n%s", 
         "Enter account number (> 0), first name, last name and balance.",
         "? " );

		while (input.hasNext()) { // loop until end-of-file indicator
			try {
				accountNumber = input.nextInt(); // read account number
				firstName = input.next(); // read first name
				lastName = input.next(); // read last name
				balance = input.nextDouble(); // read balance

				if (accountNumber > 0) {
					// create new record
					record = new AccountRecord( accountNumber, firstName, lastName, balance );
					output.writeObject( record ); // output record
				} 
				else {
					System.out.println("Account number must be greater than 0.");
				} 
			} 
			catch ( IOException ioException ) {
				System.err.println( "Error writing to file." );
				return;
			} 
			catch ( NoSuchElementException elementException ) {
				System.err.println( "Invalid input. Please try again." );
				input.nextLine(); // discard input so user can try again
			} 

			System.out.printf( "%s %s\n%s", "Enter account number (>0),",
            "first name, last name and balance.", "? " );
		}
	} 

	// close file and terminate application 
	public void closeFile() {
		try  {
			if (output != null)
				output.close();
		} 
		catch ( IOException ioException ){
			System.err.println( "Error closing file." );
			System.exit( 1 );
      	} 
   	} 
}