Can you list the types of operations that can be performed with streams?

In Java Stream API, operations are divided into intermediate and terminal.

Intermediate operations return a new Stream and allow building a data processing pipeline:

• filter(Predicate) — filtering elements
• map(Function) — transforming elements
• flatMap(Function) — transforming with unwrapping nested streams
• distinct() — removing duplicates
• sorted() and sorted(Comparator) — sorting
• limit(long) — limiting the number of elements
• skip(long) — skipping the first elements

Terminal operations complete the processing and return a result or a side effect:

• forEach(Consumer) — performing an action for each element
• collect(Collector) — collecting elements into a collection or other structure
• reduce(BinaryOperator) — folding elements into a single value
• count() — counting elements
• anyMatch(Predicate), allMatch(Predicate), noneMatch(Predicate) — condition checks
• findFirst(), findAny() — finding an element

Example:

List<String> names = Arrays.asList("Anna", "Bob", "Alice", "Brian");
List<String> filtered = names.stream()
    .filter(s -> s.startsWith("A"))
    .map(String::toUpperCase)
    .sorted()
    .collect(Collectors.toList());
// filtered = ["ALICE", "ANNA"]