July 2023
Intermediate to advanced
276 pages
6h 55m
English
Content preview from Functional Programming in Java, 2nd EditionBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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Refactoring Data Grouping Operations
Grouping data based on some criteria is a common operation in business applications. We may want to group employees based on their work location, projects based on their business units, products based on their latest revenues, and so on. Creating a Map for the group and adding values for its keys can get verbose in the imperative style and may also involve some inefficiencies. You’ll see a stark contrast between the imperative style version of code that does such processing and its equivalent functional style code.
To gain insight into refactoring code that does grouping operations, we’ll take a collection of hypothetical scores from a game, provided as key-value pairs of player names and scores. Let’s start ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.