The Java Streams API allows developers to process collections of objects in a functional way by abstracting the elements into a stream. Streams can be created from concrete collection implementations like lists or maps, then operated on through filter, map, and reduce operations before being collected back into a concrete result like a list or map. Streams make complex collection logic easier to understand and maintain, require less code, and improve performance by avoiding mutations and ensuring thread safety.

1. Java Streams API

2. What is a Stream
AN ABSTRATION
FOCUSES ON THE ALL INSTEAD OF THE PARTS

3. What is a Stream
IMPERATIVE TO FUNCTIONAL PROGRAMMING
USED WITH COLLECTIONS

5. How to use Java Streams
1 - START WITH CONCRETE IMPLEMENTATION
ARRAYS
SET
LISTS
MAPS

6. How to use Java Streams
2
concrete.stream() Sn
ABSTRACTION WHAT WE WANT
stream stream stream
filter map reduce

7. How to use Java Streams
LIST
INT
OBJECT
OPTIONAL
STRING
3
BACK TO CONCRETE
sum()
collect(Collectors.toList())
average()
collect(Collectors.groupingBy())

9. Benefits of Steams
EASIER TO UNDERSTAND
MAINTAINABLE
LESS CODE FOR COMPLEX LOGIC
PERFORMANCE
NO NEED TO WORRY ABOUT THREAD SAFETY
NO MUTATING
WRITE MORE CODE