StringTokenizer in Java

StringTokenizer
Methods of StringTokenizer
Example of StringTokenizer

The java.util.StringTokenizer class allows you to break a String into tokens. It is simple way to break a String. It is a legacy class of Java.

It doesn't provide the facility to differentiate numbers, quoted strings, identifiers etc. like StreamTokenizer class. We will discuss about the StreamTokenizer class in I/O chapter.

In the StringTokenizer class, the delimiters can be provided at the time of creation or one by one to the tokens.

Constructors of the StringTokenizer Class

There are 3 constructors defined in the StringTokenizer class.

Constructor	Description
StringTokenizer(String str)	It creates StringTokenizer with specified string.
StringTokenizer(String str, String delim)	It creates StringTokenizer with specified string and delimiter.
StringTokenizer(String str, String delim, boolean returnValue)	It creates StringTokenizer with specified string, delimiter and returnValue. If return value is true, delimiter characters are considered to be tokens. If it is false, delimiter characters serve to separate tokens.

Methods of the StringTokenizer Class

The six useful methods of the StringTokenizer class are as follows:

Methods	Description
boolean hasMoreTokens()	It checks if there is more tokens available.
String nextToken()	It returns the next token from the StringTokenizer object.
String nextToken(String delim)	It returns the next token based on the delimiter.
boolean hasMoreElements()	It is the same as hasMoreTokens() method.
Object nextElement()	It is the same as nextToken() but its return type is Object.
int countTokens()	It returns the total number of tokens.

Example of StringTokenizer Class

Let's see an example of the StringTokenizer class that tokenizes a string "my name is khan" on the basis of whitespace.

Simple.java

import java.util.StringTokenizer;
public class Simple{
 public static void main(String args[]){
   StringTokenizer st = new StringTokenizer("my name is khan"," ");
     while (st.hasMoreTokens()) {
         System.out.println(st.nextToken());
     }
   }
}

Output:

my
name
is
khan

The above Java code, demonstrates the use of StringTokenizer class and its methods hasMoreTokens() and nextToken().

Example of nextToken(String delim) method of the StringTokenizer class

Test.java

import java.util.*;

public class Test {
   public static void main(String[] args) {
       StringTokenizer st = new StringTokenizer("my,name,is,khan");
      
      // printing next token
      System.out.println("Next token is : " + st.nextToken(","));
   }    
}

Output:

Next token is : my

Note: The StringTokenizer class is deprecated now. It is recommended to use the split() method of the String class or the Pattern class that belongs to the java.util.regex package.

Example of hasMoreTokens() method of the StringTokenizer class

This method returns true if more tokens are available in the tokenizer String otherwise returns false.

StringTokenizer1.java

import java.util.StringTokenizer;  
public class StringTokenizer1
{  
 /* Driver Code */
 public static void main(String args[])
 {  
   /* StringTokenizer object */
   StringTokenizer st = new StringTokenizer("Demonstrating methods from StringTokenizer class"," ");  
     /* Checks if the String has any more tokens */
     while (st.hasMoreTokens()) 
     {  
         System.out.println(st.nextToken());  
     }  
 }  
}

Output:

Demonstrating
methods
from
StringTokenizer
class

The above Java program shows the use of two methods hasMoreTokens() and nextToken() of StringTokenizer class.

Example of hasMoreElements() method of the StringTokenizer class

This method returns the same value as hasMoreTokens() method of StringTokenizer class. The only difference is this class can implement the Enumeration interface.

StringTokenizer2.java

import java.util.StringTokenizer;  
public class StringTokenizer2
{  
 public static void main(String args[])
 {  
   StringTokenizer st = new StringTokenizer("Hello everyone I am a Java developer"," ");  
     while (st.hasMoreElements()) 
     {  
         System.out.println(st.nextToken());  
     }  
 }  
}

Output:

Hello
everyone
I
am
a
Java
developer

The above code demonstrates the use of hasMoreElements() method.

Example of nextElement() method of the StringTokenizer class

nextElement() returns the next token object in the tokenizer String. It can implement Enumeration interface.

StringTokenizer3.java

import java.util.StringTokenizer;  
public class StringTokenizer3
{  
 /* Driver Code */
 public static void main(String args[])
 {  
   /* StringTokenizer object */
   StringTokenizer st = new StringTokenizer("Hello Everyone Have a nice day"," ");  
     /* Checks if the String has any more tokens */
     while (st.hasMoreTokens()) 
     {  
         /* Prints the elements from the String */
         System.out.println(st.nextElement());  
     }  
 }  
}

Output:

Hello
Everyone
Have
a
nice
day

The above code demonstrates the use of nextElement() method.

Example of countTokens() method of the StringTokenizer class

This method calculates the number of tokens present in the tokenizer String.

StringTokenizer4.java

import java.util.StringTokenizer;  
public class StringTokenizer3
{  
 /* Driver Code */
 public static void main(String args[])
 {  
   /* StringTokenizer object */
   StringTokenizer st = new StringTokenizer("Hello Everyone Have a nice day"," ");  
         /* Prints the number of tokens present in the String */
         System.out.println("Total number of Tokens: "+st.countTokens());  
 }  
}

Output: