Exception in thread main java util NoSuchElementException

Question

Whenever I run this  the chooseCave   function works fine with the in nextInt    When I choose the cave  the messages pop up at 2-second intervals  and then as soon as it gets past that part  it gives me the error   Exception in thread  main  java util NoSuchElementException  No line found     at java util Scanner nextLine Unknown Source      at Dragon main Dragon java 81    I have tried hasNextLine   and hasNextInt    and when I use while hasNextLine   in the main method  I get a ton more errors  When I use while hasNextInt   in the chooseCave   method  it doesn t accept my input   When I use if hasNextInt   in the chooseCave   method  it doesn t accept my input for the playAgain string  and goes straight into another game  but then the hasNextInt   boolean returns false and it spams  Which cave     infinitely   I ve gone through the error reports and the Java-docs and Stack Overflow s with similar problems  Please help   import java util Scanner  public class Dragon    public static void displayIntro         System out println  You are in a land full of dragons  In front of you          System out println  You see two caves  In one cave  the dragon is friendly        System out println  and will share his treasure with you  The other dragon        System out println  is greedy and hungry  and will eat you on sight        System out println          public static int chooseCave         Scanner in   new Scanner System in       int cave   0      while  cave    1  amp  amp  cave    2            System out println  Which cave will you go into   1 or 2              cave   in nextInt               in close        return cave      public static void checkCave int chosenCave        System out println  You approach the cave           try                    Sleep at least n milliseconds            1 millisecond   1 1000 of a second         Thread sleep  2000                 catch   InterruptedException e                   System out println   awakened prematurely                  System out println  It is dark and spooky           try                    Sleep at least n milliseconds            1 millisecond   1 1000 of a second         Thread sleep  2000                 catch   InterruptedException e                   System out println   awakened prematurely                  System out println  A large dragon jumps out in front of you  He opens his jaws and           try                    Sleep at least n milliseconds            1 millisecond   1 1000 of a second         Thread sleep  2000                 catch   InterruptedException e                   System out println   awakened prematurely                   double friendlyCave   Math ceil Math random     2        if  chosenCave    friendlyCave            System out println  Gives you his treasure               else           System out println  Gobbles you down in one bite                public static void main String   args        Scanner inner   new Scanner System in       String playAgain    yes       boolean play   true      while  play            displayIntro            int caveNumber   chooseCave            checkCave caveNumber           System out println  Do you want to play again   yes or no             playAgain   inner nextLine            if  playAgain     yes                 play   true                    else               play   false                      inner close

User · Answer

simply don t close in  remove in close   from your code

User · Answer

You close the second Scanner which closes the underlying InputStream  therefore the first Scanner can no longer read from the same InputStream and a NoSuchElementException results   The solution  For console apps  use a single Scanner to read from System in   Aside  As stated already  be aware that Scanner nextInt does not consume newline characters  Ensure that these are consumed before attempting to call nextLine again by using Scanner newLine     See  Do not create multiple buffered wrappers on a single InputStream

User · Answer

The nextInt   method leaves the  n  end line  symbol and is picked up immediately by nextLine    skipping over the next input   What you want to do is use nextLine   for everything  and parse it later   String nextIntString   keyboard nextLine      get the number as a single line int nextInt   Integer parseInt nextIntString     convert the string to an int   This is by far the easiest way to avoid problems--don t mix your  next  methods   Use only nextLine   and then parse ints or separate words afterwards     Also  make sure you use only one Scanner if your are only using one terminal for input   That could be another reason for the exception     Last note  compare a String with the  equals   function  not the    operator   if  playAgain     yes       Causes problems if  playAgain equals  yes        Works every time

User · Answer

Reimeus is right  you see this because of in close in your chooseCave    Also  this is wrong   if  playAgain     yes           play   true      You should use equals instead of        if  playAgain equals  yes            play   true

User · Answer

Everyone explained pretty well on it  Let me answer when should this class be used   When Should You Use NoSuchElementException   Java includes a few different ways to iterate through elements in a collection  The first of these classes  Enumeration  was introduced in JDK1 0 and is generally considered deprecated in favor of newer iteration classes  like Iterator and ListIterator    As with most programming languages  the Iterator class includes a hasNext   method that returns a boolean indicating if the iteration has anymore elements  If hasNext   returns true  then the next   method will return the next element in the iteration  Unlike Enumeration  Iterator also has a remove   method  which removes the last element that was obtained via next      While Iterator is generalized for use with all collections in the Java Collections Framework  ListIterator is more specialized and only works with List-based collections  like ArrayList  LinkedList  and so forth  However  ListIterator adds even more functionality by allowing iteration to traverse in both directions via hasPrevious   and previous   methods

[java] Exception in thread "main" java.util.NoSuchElementException

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