In previous article, we have discussed about StringTokenizer class with various delimiters for splitting a String
Next question is,
Q) Whether it is possible to count number of tokens after splitting a String ?
- Yes, it is possible to count number of tokens after splitting string
- using countTokens() method of StringTokenizer class
Method Signature:
public int countTokens();
Note:
- StringTokenizer is deprecated now, but however it is carried forward for backward compatibility
- Instead of countTokens() method of StringTokenizer, developer should prefer using length() method of String class after splitting
Let us move forward to discuss an example on how to count number of tokens using StringTonizer’s countTokens() method
1. Count number of tokens when space is used as delimiter
Syntax:
StringTokenizer st1 = new StringTokenizer(str);
CountTokensAfterSplittingUsingSpaceAsDelimiter.java
package in.bench.resources.java.stringtokenizer.example;
import java.util.StringTokenizer;
public class CountTokensAfterSplittingUsingSpaceAsDelimiter {
public static void main(String[] args) {
// sample string
String str = "Water Wind Earth Sky Fire";
// create StringTokenizer object
StringTokenizer st = new StringTokenizer(str);
System.out.println("Number of tokens,"
+ " after String split : " + st.countTokens());
// iterate through StringTokenizer tokens
while(st.hasMoreTokens()) {
System.out.println("\nToken value is : "
+ st.nextToken());
System.out.println("After iteration,"
+ " number of tokens reduced to : "
+ st.countTokens());
}
}
}
Output:
Number of tokens, after String split : 5
Token value is : Rain
After iteration, number of tokens reduced to : 4
Token value is : Wind
After iteration, number of tokens reduced to : 3
Token value is : Earth
After iteration, number of tokens reduced to : 2
Token value is : Fire
After iteration, number of tokens reduced to : 1
Token value is : Sky
After iteration, number of tokens reduced to : 0
2. Count number of tokens when comma(,) is used as delimiter
Syntax:
StringTokenizer st2 = new StringTokenizer(str, “,”);
CountTokensAfterSplittingUsingCommaAsDelimiter.java
package in.bench.resources.java.stringtokenizer.example;
import java.util.StringTokenizer;
public class CountTokensAfterSplittingUsingCommaAsDelimiter {
public static void main(String[] args) {
// sample string
String str = "Apple,Banana,Mango,Orange,";
// create StringTokenizer object
StringTokenizer st = new StringTokenizer(str, ",");
System.out.println("Number of tokens,"
+ " after String split : " + st.countTokens());
// iterate through StringTokenizer tokens
while(st.hasMoreTokens()) {
System.out.println("\nToken value is : "
+ st.nextToken());
System.out.println("After iteration,"
+ " number of tokens reduced to : "
+ st.countTokens());
}
}
}
Output:
Number of tokens, after String split : 4
Token value is : Apple
After iteration, number of tokens reduced to : 3
Token value is : Banana
After iteration, number of tokens reduced to : 2
Token value is : Mango
After iteration, number of tokens reduced to : 1
Token value is : Orange
After iteration, number of tokens reduced to : 0
3. Count number of tokens when pipe(|) is used as delimiter
Syntax:
StringTokenizer st2 = new StringTokenizer(str, “|”);
CountTokensAfterSplittingUsingPipeAsDelimiter.java
package in.bench.resources.java.stringtokenizer.example;
import java.util.StringTokenizer;
public class CountTokensAfterSplittingUsingPipeAsDelimiter {
public static void main(String[] args) {
// sample string
String str = "Bob|25|Engineer";
// create StringTokenizer object
StringTokenizer st = new StringTokenizer(str, "|");
System.out.println("Number of tokens,"
+ " after String split : " + st.countTokens());
// iterate through StringTokenizer tokens
while(st.hasMoreTokens()) {
System.out.println("\nToken value is : "
+ st.nextToken());
System.out.println("After iteration,"
+ " number of tokens reduced to : "
+ st.countTokens());
}
}
}
Output:
Number of tokens, after String split : 3
Token value is : Bob
After iteration, number of tokens reduced to : 2
Token value is : 25
After iteration, number of tokens reduced to : 1
Token value is : Engineer
After iteration, number of tokens reduced to : 0
Hope, you found this article very helpful. If you have any suggestion or want to contribute any other way or tricky situation you faced during Interview hours, then share with us. We will include that code here.
Related Articles:
- Java – How to split String based on space & dot(.) as delimiter ?
- Java – How to split String using pipe(|) as delimiter ?
- Java – StringTokenizer class with example
- Java – Counting number of tokens using StringTokenizer
- Java – Reversing a String by word using StringTokenizer
- Java – Count and print number of words and lines in a text file
- Java – Count and print number of repeated word occurrences in a String
- Java – Count and print number of repeated character occurrences in a String
References:
- https://docs.oracle.com/javase/tutorial/essential/concurrency/immutable.html
- https://docs.oracle.com/javase/tutorial/essential/concurrency/imstrat.html
- https://docs.oracle.com/javase/tutorial/java/data/strings.html
- https://docs.oracle.com/javase/8/docs/api/java/lang/String.html
- https://docs.oracle.com/javase/8/docs/api/java/lang/class-use/String.html
- https://docs.oracle.com/javase/8/docs/api/java/lang/StringBuffer.html
- https://docs.oracle.com/javase/8/docs/api/java/lang/StringBuilder.html
Happy Coding !!
Happy Learning !!
