Java.util.Scanner.hasNext() Method

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Description

The java.util.Scanner.hasNext(Pattern pattern) method returns true if the next complete token matches the specified pattern. A complete token is prefixed and postfixed by input that matches the delimiter pattern. This method may block while waiting for input. The scanner does not advance past any input.

Declaration

Following is the declaration for java.util.Scanner.hasNext() method

public boolean hasNext(Pattern pattern)

Parameters

  • pattern -- the pattern to scan for

Return Value

This method returns true if and only if this scanner has another token matching the specified pattern

Exception

  • IllegalStateException -- if this scanner is closed

Example

The following example shows the usage of java.util.Scanner.hasNext() method.

package com.tutorialspoint;

import java.util.*;
import java.util.regex.Pattern;

public class ScannerDemo {

   public static void main(String[] args) {

      String s = "Hello World! 3+3.0=6";

      // create a new scanner with the specified String Object
      Scanner scanner = new Scanner(s);

      // check if the scanner's next token matches "rld" following 2 chars
      System.out.println("" + scanner.hasNext(Pattern.compile("..rld")));

      // check if the scanner's next token matches "llo" following 2 chars
      System.out.println("" + scanner.hasNext(Pattern.compile("..llo")));

      // print the rest of the string
      System.out.println("" + scanner.nextLine());

      // close the scanner
      scanner.close();
   }
}

Let us compile and run the above program, this will produce the following result:

false
true
Hello World! 3+3.0=6



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