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POScanner not working properly
 

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  1. POScanner not working properly
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    <p>Hello again fellow programmers. I have another problem that's puzzling me. I am trying to receive input from a user but always receive an "java.util.NoSuchElementException: No line found". I have tried all the methods I've searched with no luck. Here is my code:</p> <pre><code>import java.util.Scanner; import java.io.*; public class UserLog { static String username; static String password; static String passcompare; static File name; static String Userfile = "username-"; static String Passfile = "password-"; public static void main(String[] args) { menu(); } public static void menu(){ boolean call = false; try (Scanner in = new Scanner(System.in)) { do { System.out.println("Select an option: "); System.out.println("1: New account \n" + "2: Existing account"); System.out.print("-"); int choice = in.nextInt(); in.nextLine(); switch(choice) { case 1: call = true; System.out.println("\nNew account called\n"); userCreate(); break; case 2: call = true; System.out.println("\nExisting account called\n"); login(); break; default: System.out.println("\nNot a valid option\n"); } } while(!call); in.close(); } catch(Exception ex) { System.out.println("Exception Text: " + ex); } } static void login(){ try (Scanner in = new Scanner(System.in)) { System.out.println("LOGIN SCREEN\n"); System.out.print("Username: "); username = in.nextLine(); name = new File("user-" + username + ".txt"); if(name.exists()) { System.out.println("Username exists"); System.out.print("Password: "); password = in.nextLine(); //scans userfile for password if(password.length() != 0 &amp;&amp; password.length() &gt;= 8 /* and password-username match */) { System.out.println("Login successful"); in.close(); } } else { System.out.println("Username doesn't exist in system"); System.out.println("Would you like to create this user? (y/n)"); System.out.print("-"); char choice = (char)System.in.read(); switch(choice) { case 'Y': case 'y': System.out.println("Creating user " + username); name = new File("user-" + username + ".txt"); name.createNewFile(); System.out.println("User created"); passCreate(name); in.close(); break; case 'N': case 'n': System.out.println("Denied creation of user"); in.close(); break; default: System.out.println(); } } in.close(); } catch (IOException ex) { System.out.println("Exception Text: " + ex); } } private static File nameCreate() { try (Scanner user = new Scanner(System.in)) { System.out.print("Enter Username: "); username = user.nextLine(); name = new File("user-" + username + ".txt"); if(!name.exists()) { name.createNewFile(); try (FileWriter fw = new FileWriter(name)) { fw.write(Userfile + username + "\n"); fw.write(Passfile); fw.flush(); fw.close(); } catch(Exception ex) { System.out.println("Exception Text: " + ex); } //puts lines of text in the file- //username-"username" //password- // System.out.println("User Created\n"); } else if(name.exists()) { System.out.println("User already exists\n"); nameCreate(); } user.close(); } catch(Exception ex) { System.out.println("Exception Text: " + ex); } return name; } private static void passCreate(File user) { username = user.toString(); System.out.println(username + "\n"); boolean code = false; try (Scanner pass = new Scanner(System.in)) { do{ //opens file and reads until line "password-" and appends it with created password once confirmed System.out.println("Create a password"); System.out.print("Password: "); password = pass.nextLine(); if(password.length() &gt;= 8) { System.out.print("Confirm Password: "); passcompare = pass.nextLine(); if(password.equals(passcompare)) { code = true; System.out.println("Passwords match\n"); //stores password } else { System.out.println("Passwords don't match\n"); } } else { System.out.println("Password needs to be longer than 8 characters\n"); } }while(!code); pass.close(); } catch(Exception ex) { System.out.println("Exception Text: " + ex); } } private static void userCreate() { nameCreate(); passCreate(name); } } </code></pre> <p>It's ugly and incomplete, I know, but this problem has kept me from going further. I am able to get to the password creation if I go through existing user option and create a user that way, but if I try to go through the create new user, I get the no line exception. My question is: how do I create more lines for the scanner to use to be able to create a password, or what other options do I have for completing this task. I've tried hasNextLine() and that's what made me realize that there are no more lines. Thanks</p>
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    1. PO
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    1. This table or related slice is empty.
    1. PTQuestion
    1. USVulcan
    1. USTechnicalCustoms
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    1. PL
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    1. This table or related slice is empty.
    1. PO
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    1. COIs it possible to only show us the part of the code that is relevant to the `NoSuchElementException`?
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      1. USDennis Meng
    2. CORelevant, and may answer your question: http://stackoverflow.com/questions/13042008/java-util-nosuchelementexception-scanner-reading-user-input
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      1. POScanner not working properly
      1. USDennis Meng
    3. COyes, but it only happens when going through option 1 at the beginning of the program. it's in the passCreate function
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      1. POScanner not working properly
      1. USTechnicalCustoms
 

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