Green Cup

JAVA 8 STREAM API METHODS

MASTER FUNCTIONAL PROGRAMMING WITH STREAMS

INTRO TO JAVA 8 STREAM API

Java 8 Stream API helps process collections in a declarative & functional style. Ideal for filtering, mapping, reducing, and collecting data efficiently.

WHAT IS A STREAM ?

A Stream is not a data structure It's a conveyor of data from a source (like a List) Stream operations are chained, lazy, and parallelizable

STREAM CREATION

Other ways : Stream.of()  Arrays.stream() Files.lines()

Stream stream = list.stream();

INTERMEDIATE OPERATIONS

Common intermediate methods: filter() map() distinct() sorted() limit(), skip() They return a stream, enabling method chaining.

TERMINAL OPERATIONS

These trigger execution: forEach() collect() reduce() count() anyMatch() Terminal operations produce a result or side-effect.

PARALLEL STREAMS

Use parallelStream() for multi-threaded data processing. ⚠️ Use wisely to avoid performance issues.

list.parallelStream()    .filter(...)    .collect(...);

BENEFITS OF STREAM API

✔ Code is more readable ✔ Supports functional programming ✔ Enables parallelism ✔ Great for big data processing 📖 Read full tutorial: javacody.com