Java Functional Programming

Operations: 

Intermediate(transform a stream to another):

• Map
• flatMap 
• Filter
• Collect
• forEach 
• Reduce
• Sorted
• peek
• limit 
• skip 

Terminal operation:

• forEach
• Terminal
• count
• reduce
• collect
• anyMatch
• allMatch
• noneMatch
• findFirst
• findAny
• min
• max
• toArray

More details:

• Fundamentals
• Concepts
• Techniques
• Functional Composition

There are two ways to achieve Function composition. They are compose and andThen.

Function<Integer, Integer> sum = x -> x + x; 

Function<Integer, Integer> square = y -> y * y;  

Integer sumAndSquareResult = sum.compose(square).apply(3); // Returns 18

Integer squareAndSumResult = sum.andThen(square).apply(3); // Returns 36