[hardwired]

Code:

JTextField phoneJTextField    = new JTextField("Beachwood 45789");
JTextField postcodeJTextField = new JTextField("99231");
Writer fw = null; 

try 
{ 
    fw = new FileWriter( "customer.txt" ); 
    String phoneNumber = phoneJTextField.getText();
    String postalCode = postcodeJTextField.getText();
    fw.write( phoneNumber + "," + postalCode ); 
}
catch ( IOException e ) { 
    System.err.println( "Cannot write to file" ); 
} 
finally { 
    if ( fw != null ) 
    try {
        fw.close();
    } catch ( IOException e ) {
        System.out.println("Close error: " + e.getMessage());
    } 
}