What is StringJoiner in Java?
In Java, we can use StringJoiner to join strings with a separator. We can also choose to specify the prefix and suffix added to the result strings.
Syntax
StringJoiner(CharSequence delimiter)
StringJoiner(CharSequence delimiter, CharSequence prefix, CharSequence suffix)
To use StringJoiner, create a StringJoinerobject and call the add method by passing the string to be joined.
Code
import java.util.StringJoiner;class JoinString {public static void main( String args[] ) {StringJoiner joiner = new StringJoiner(", ");joiner.add("I");joiner.add("Love").add("Badminton");System.out.println(joiner.toString());}}
In the code above, we:
-
Created a
StringJoinerwith,as the separator of the string. -
Used the
add()method to add some strings to theStringJoiner. This method returns the reference to theStringJoinerto chain theadd()method. -
Called the
toString()method to convert theStringJoinerinto a string. The resultant string is the joined version of all strings separated by the separator.
Example with prefix and suffix
import java.util.StringJoiner;class JoinString {public static void main( String args[] ) {String SEPARATOR = "-";String PREFIX = "{";String SUFFIX = "}";StringJoiner joiner;joiner = new StringJoiner(SEPARATOR, PREFIX, SUFFIX);joiner.add("I");joiner.add("Love").add("Badminton");System.out.println(joiner.toString());}}
In the code above, we created a StringJoiner named joiner with - as a separator, { as PREFIX, and } as SUFFIX.
The resulting string will start with {, end with }, and the separator - will be added between the strings.
