Solutions to join a list of strings using another character in Java 8 Stream API and a lambda expression
Solution 1: Simple Logic
import java.util.List;
import java.util.stream.Collectors;
public class StringJoiner {
public static String join(List<String> list, String delimiter) {
return list.stream()
// Add the delimiter after each element except the last
.collect(Collectors.joining(delimiter, "", ""));
}
public static void main(String[] args) {
List<String> names = List.of("Alice", "Bob", "Charlie");
String result = join(names, "-");
System.out.println(result); // Output: Alice-Bob-Charlie
}
}Solution 2: Logic with a conditional flow
A solution to join a list of strings using another character in Java 8 stream API and lambda expression with a condition that the String is not equal to “Alice”
import java.util.Arrays;
import java.util.List;
public class StringJoiningExample {
public static void main(String[] args) {
List<String> names = Arrays.asList("Alice", "Bob", "Charlie", "Alice", "David");
String delimiter = ", "; // Use comma as the delimiter
// Use Stream API to filter, filter again, and join strings
String joinedNames = names.stream()
.filter(name -> !name.equals("Alice")) // Exclude "Alice"
.distinct() // Remove duplicates
.collect(Collectors.joining(delimiter));
System.out.println("Joined names: " + joinedNames); // Output: Bob, Charlie, David
}
}Solution 3: Logic to find a distinct and sorted result
A solution to join a list of strings using another character in Java 11 stream API and lambda expression with a condition that the String is not equal to “Alice”. find distinct and sort the results in ascending order
import java.util.Arrays;
import java.util.List;
public class StringJoiningExample {
public static void main(String[] args) {
List<String> names = Arrays.asList("Alice", "Bob", "Charlie", "Alice", "David");
String delimiter = ", "; // Use comma as the delimiter
// Use Stream API to filter, filter again, and join strings
String joinedNames = names.stream()
.filter(name -> !name.equals("Alice")) // Exclude "Alice"
.distinct() // Remove duplicates
.collect(Collectors.joining(delimiter));
System.out.println("Joined names: " + joinedNames); // Output: Bob, Charlie, David
}
}Do you have a specific requirement other than these? Feel free to ask in the comments we would like to help further 🙂
Further Readings
- Official documentation of Java 8 Streams – https://docs.oracle.com/javase/8/docs/api/java/util/stream/package-summary.html
- Check out our other blogs on Core Java and Java 8
