1 What is StringTokenizer?
A StringTokenizer is a class in Java. It is used to divide strings in form of token based on some delimiters.
It is defined in java.util.stringtokenizer
2 StringTokenizer Constructors
| Sr No | Constructor and Description |
|---|---|
| 1 | StringTokenizer(String str) Construct a string tokenizer for given string |
| 2 | StringTokenizer(String str, String delim) Construct a string tokenizer for given string and generate tokens based on delimiters |
| 3 | StringTokenizer(String str, String delim, boolean returnDelims) Construct a string tokenizer for given string and generate tokens based on delimiters the returnDelims specify whether to include delim in token or not |
Creating StringTokenizer object using first constructor
StringTokenizer st = new StringTokenizer("Arise awake and do not stop until the goal is reached");
Creating StringTokenizer object using second constructor
StringTokenizer st = new StringTokenizer("Hello, how, are, you",",");
3 StringTokenizer methods
A Java StringTokenizer countTokens() Method
This method is used to count the number of the tokens from current token position to the last token
Signature
public int countTokens()
Parameters
NA
Return
Return the number of tokens available from specific token position
Example
package ebhor;
import java.util.StringTokenizer;
public class JavaStringTokenCount {
public static void main(String[] args) {
StringTokenizer st = new StringTokenizer("Arise awake and do not stop until the goal is reached");
int tokenCount = st.countTokens();
System.out.println("Total Numbers of tokens are " + tokenCount);
st.nextToken();
tokenCount = st.countTokens();
System.out.println("Total Numbers of tokens are " + tokenCount);
}
}
Total Numbers of tokens are 11 Total Numbers of tokens are 10
Initially token position was before the first word “Arise” so on calling st.countToken() returns 11.
on calling st.nextToken() position of token is incresed by one and it is on “Arise” from this position new token count is 10.
import java.util.StringTokenizer;
public class TokenCount1 {
public static void main(String[] args) {
StringTokenizer st = new StringTokenizer("Arise awake and do not stop until the goal is reached");
int tokenCount = st.countTokens();
String token;
System.out.println("Total Numbers of tokens are " + tokenCount);
while (st.hasMoreTokens()) {
token = st.nextToken();
tokenCount = st.countTokens();
System.out.println("Next Token " + token + " token count from this position " + tokenCount);
}
}
}
Total Numbers of tokens are 11 Next Token Arise token count from this position 10 Next Token awake token count from this position 9 Next Token and token count from this position 8 Next Token do token count from this position 7 Next Token not token count from this position 6 Next Token stop token count from this position 5 Next Token until token count from this position 4 Next Token the token count from this position 3 Next Token goal token count from this position 2 Next Token is token count from this position 1 Next Token reached token count from this position 0
B Java StringTokenizer hasMoreElements() Method
This method checks for next token in StringTokenizer if the token exists then return true else return false. Work similar as
hasMoreToken()
Parameters
NA
Return
Return true if next token exists else return false
Example
package ebhor;
import java.util.StringTokenizer;
public class StringTokenizer5 {
public static void main(String[] args) {
StringTokenizer st=new StringTokenizer("Java is secure language");
boolean b=st.hasMoreElements();
System.out.println("Has More Element :"+b);
}
}
Result
Has More Element :true
At starting object st is pointing before the first word(Java). on calling st.hasMoreElements it is checkin that the first word java is there so it is returning true.
C Java StringTokenizer hasMoreToken() Method
This method is used with StringTokenizer object to check whether there is more token or not
For exampleStringTokenizer st=new StringTokenizer(“Hello Friends”);
There are two tokens Hello and Friends. At starting hasMoreToken() point before the Hello Token so calling this method will return true at first.
To get next token we use nextToken().
After getting token Friends, again calling hasMoreToken() it return false.
Signature
public boolean hasMoreToken()
Parameters
NA
Return
Return true if there is more token else return false
Example
public class StringTokenizerExample3 {
public static void main(String[] args) {
StringTokenizer st = new StringTokenizer("Hello Friends");
boolean b = st.hasMoreTokens();
System.out.println("Has more token " + b);
}
}
Result
Has more token true
St object is pointing before the Hello so calling st.hasMoreTokens() will always return true.
D Java StringTokenizer nextElement() Method
This method returns next token from stringTokenizer object this method work same as nextToken() only the return type of this method is object instead of String
Signature
public Object nextElement()
Parameters
NA
Return
Return next token from StringTokenizer object
Throws
NoSuchElementException – If there is no token in StringTokenizer object then it throw this exception
Example
Lets see how to tokenize a string in java
package ebhor;
import java.util.StringTokenizer;
public class StringTokenizerExample2 {
public static void main(String[] args) {
StringTokenizer st = new StringTokenizer("Hello Friends");
boolean hasMoreElement;
Object nextElement;
hasMoreElement = st.hasMoreElements();
System.out.println("Has more element " + hasMoreElement);
nextElement = st.nextElement();
System.out.println("next element is " + nextElement);
hasMoreElement = st.hasMoreElements();
System.out.println("Has more element " + hasMoreElement);
nextElement = st.nextElement();
System.out.println("next element is " + nextElement);
hasMoreElement = st.hasMoreElements();
System.out.println("Has more element " + hasMoreElement);
}
}
Has more element true next element is Hello Has more element true next element is Friends Has more element false
Another Example
package ebhor;
import java.util.StringTokenizer;
public class JavaStringTokenizer4 {
public static void main(String[] args) {
StringTokenizer st = new StringTokenizer("Hello Friends How Are You");
while(st.hasMoreElements())
{
System.out.println("Next Element is " + st.nextElement());
}
}
}
Next Element is Hello Next Element is Friends Next Element is How Next Element is Are Next Element is You
E Java StringTokenizer nextToken() Method
This method returns next token from stringTokenizer object
Signature
public String nextToken()
Parameters
NA
Return
Return next token from StringTokenizer object
Throws
NoSuchElementException – If there is no token in StringTokenizer object then it throw this exception
Example
public class StringTokenizerExample1 {
public static void main(String[] args) {
StringTokenizer st = new StringTokenizer("Hello Friends");
boolean moreToken;
String nextToken;
moreToken = st.hasMoreTokens();
nextToken = st.nextToken();
System.out.println("Has more Token " + moreToken + " next token is " + nextToken);
moreToken = st.hasMoreTokens();
nextToken = st.nextToken();
System.out.println("Has more Token " + moreToken + " next token is " + nextToken);
moreToken = st.hasMoreTokens();
System.out.println("Has more Token " + moreToken);
}
}
public class StringTokenizerExample1 {
public static void main(String[] args) {
StringTokenizer st = new StringTokenizer("Hello Friends");
boolean moreToken;
String nextToken;
while (moreToken = st.hasMoreTokens()) {
nextToken = st.nextToken();
System.out.println("Has more Token " + moreToken + " next token is " + nextToken);
}
}
Result
Has more Token true next token is Hello Has more Token true next token is Friends Has more Token false
Has more Token true next token is Hello Has more Token true next token is Friends