I am trying to read a txt file with this format (heading not included):
firstname lastname username password
John Doe $1234567 $123
Eden Hask $1234576 $12345
The latest login (Eden) would always work but not the one prior(John). For some reason, the delimiter would include all details until the next $. How should I get my delimiter to stop after the password.
The user name is_1234567 and the password is_123
Eden Hask!
The user name is_1234576 and the password is_12345!
Here is the entire code.
public void login() throws FileNotFoundException{
File file = new File("file.txt");
Scanner read = new Scanner(file);
found = false;
read.useDelimiter("(\s*\\$)");
try {
Scanner keyboard = new Scanner(System.in);
System.out.print("Username: ");
String username = keyboard.nextLine();
System.out.print("Password: ");
String passwordField = keyboard.nextLine();
while(read.hasNext()){
String user = read.next();
String pass = read.next();
System.out.println("The user name is_" + user + " and the password is_" + pass + "!\n");
if(user.trim().equals(username) && pass.trim().equals(passwordField)){
boolean found = true;
break;
}
}
if(found){
return true;
}
else {
return false;
}
read.close();
}catch(Exception e){
throw e;
}
};
From what you have described it looks like you also want to break your string when a line ends. To do this add a carriage return as one of delimiting cases in the following manner-
read.useDelimiter("\n|(\s*\\$)")
this should prevent all the previous 'password' strings from including details from the next line
I would do it completely different:
boolean found;
public void login() throws FileNotFoundException {
File file = new File("file.txt");
Scanner read = new Scanner(file);
try {
Scanner keyboard = new Scanner(System.in);
System.out.print("Username: ");
String username = keyboard.nextLine();
System.out.print("Password: ");
String password = keyboard.nextLine();
// Skip the first line
read.nextLine();
while (read.hasNextLine()) {
String line = read.nextLine();
//split current line with spaces into an array
String[] lineArray = line.split("\\s+");
String user = lineArray[1];
String pass = lineArray[4];
System.out.println("The user name is " + user + " and the password is " + pass + "!\n");
if (user.equals(username) && pass.equals(password)) {
found = true;
break;
}
}
read.close();
keyboard.close();
} catch (Exception e) {
e.printStackTrace();
}
}
In addition to the line break inclusion in the delimiter, you may want to read the name of the user to keep the userid/password reads in sync:
read.useDelimiter("(\\s*\\$)|(\\R)");
try {
Scanner keyboard = new Scanner(System.in);
System.out.print("Username: ");
String username = keyboard.nextLine();
System.out.print("Password: ");
String passwordField = keyboard.nextLine();
while(read.hasNext()){
String name = read.next();
String user = read.next();
String pass = read.next();
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