Let's map a list of words using Java 8 streams:
List<String> words = Arrays.asList("A", "bbb", "CC", "dd"); // Map the words to UPPERCASE and join them with the ":" separator String joined = words.stream() .map(String::toUpperCase) .collect(Collectors.joining(":")); // "A:BBB:CC:DD"
Example of mapping Java 8 streams using the
map method of a stream returns another stream with the mapped values. In this example the words are mapped into their uppercase versions, and the resulting stream is converted to a string by collecting all of its items and concatenating/joining them with a joining collector, using the