Java Streams - Collectors joining(CharSequence delimiter, CharSequence prefix, CharSequence suffix) example








Collectors joining(CharSequence delimiter, CharSequence prefix, CharSequence suffix) returns a Collector that concatenates the elements, separated by the delimiter, with the specified prefix and suffix, in encounter order.

Syntax

joining has the following syntax.

public static Collector<CharSequence,?,String> joining(CharSequence delimiter,     CharSequence prefix,     CharSequence suffix)

Example

The following example shows how to use joining.

import java.util.stream.Collectors;
import java.util.stream.Stream;
// w  w  w .j a  v  a 2 s. com
public class Main {
  public static void main(String[] args) {
    Stream<String> s = Stream.of("a","b","c");
    
    String names = s
        .collect(Collectors.joining(", ", "Hello ", ". Goodbye."));

    System.out.println(names);
  }
}

The code above generates the following result.