How does flatMap differ from a map in Java Streams?

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Question

How does flatMap() differ from map() in Java Streams?

In our past blog we have discussed what Stream API is in Java. I would recommend to go throught the above blog if you are not aware of stream API. In this blog we will discuss about what is flatMap() and map() and their differences.

map()

Let’s consider an array where we have list of names and we want to loop and print the size of each names.

List<String> names = Arrays.asList("Pavan", "Sai", "Medium");
        for (int i = 0; i < names.size(); i++) {
          System.out.println(names.get(i).length());
        }

• Now if we want to use the Stream API, How we will do that?
• Map is used to perform some transformations meaning , let’s say we wanted to…