Exception in thread “main” Java.util.NoSuchElementException

In this article, we will share with you the piece of information about Java.util.NoSuchElementException. We are going to answers the questions below:  What is Java.util.NoSuchElementException? When it occurs? How can we solve this? Thread is …

“main” Java.util.NoSuchElementException

In this article, we will share with you the piece of information about Java.util.NoSuchElementException. We are going to answers the questions below: 

  • What is Java.util.NoSuchElementException?
  • When it occurs?
  • How can we solve this?

Thread is a roadway for a java program. It involves classes methods or constructors to run an operation.

Exception in thread means unwanted, or not-likable events occur in the path to execute the program or at the time of execution.

What is Java.util.NoSuchElementException?

Java.util.NoSuchElementException if an exception arises in a java program when the programmer wants to access a java class like iterable, enumeration, scanner, or string tokenizer over its maximum limit.

When it occurs?

In the context of the following  java classes, the exception “java.util.nosuchelementexception” occurs when:

In the Iterator class, the next() method returns this exception when no iterator element is present or the iterator is empty/null.

And iterator instance returns false.

In the Enumeration class, the method nextElement() returns this exception when there is no next element is present.

In the Scanner class, the nextLine() method returns this exception when there is no next line.

In StringTokenizer class, the method nextElement() breaks a string into multiple tokens.

To understand it further, let’s take an example of a java iterator class consisting of exceptions called Java.util.NoSuchElementException.

Example:
import java.util.*;
public class Drastic {
  public static void main(String[] args) {
    ArrayList<String> arrlist = new ArrayList<String>();
    arrlist.add(new String("hello drastic family"));
    Iterator itr = arrlist.iterator();
    System.out.println(itr.next()); 
    System.out.println(itr.next());
  }
}
Output:
“main” Java.util.NoSuchElementException

How can we solve this?

To solve this, we will include the hasnext() method in iterator class if it returns true, and then we will apply hasmoreElements() to see the more elements are present or not.

How will we solve this if it is not returning true and still producing the same exception?

Well, in that case, we will check whether the iterator class is filled or empty.

To check this, we will use the hasnext() and hasmoreElement() method.

Let’s solve the Java.util.NoSuchElementException in above example by applying hasnext() method:

import java.util.*;
public class Drastic {
  public static void main(String[] args) {
    ArrayList<String> arrlist = new ArrayList<String>();
    arrlist.add(new String("hello drastic family"));
    Iterator itr = arrlist.iterator();
    while (itr.hasNext()) {
      System.out.println(itr.next());
    }
  }
}
Output:
“main” Java.util.NoSuchElementException

Similarly, we can solve this exception in other java classes also.

For the Enumeration class, you can use nextElement() method to check whether the next element is present or not or, if present, then to fetch.

For the Scanner class you can use nextLine() method

And, for Stringtokenizer class you  can use nextToken() or nextElement() method.

Conclusion:

Java.util.NoSuchElementException” is an exception in the java program when the user wants to fetch some element that is not present or the class is empty.

To solve this exception, you can use the methods given above.

Suggested Read: 500 Internal server error

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