Static Factory Methods

What is Static Factory Method?

When a static method returns the same Class Object (reference type) of its own class, its called Static Factory Method

example

Runtime r = Runtime.getRuntime();

JAVA 9 Enhancement; of() method is static factory method

// shortcut way to create UNMODIFIABLE Collection Object (no add or remove works after it)
List<Integer> l = List.of(2, 3, 4, 5, 6, 7);//upto 10 elements, post which var-arg method
// but using var arg is costly

Optional<List<String>> strOptional = Optional.of(Arrays.asList("John","Doe"));
List<String> stringList = strOptional.get();