Java Recipes Pro

A reference of everyday Java, from strings and collections to threading and design patterns. Every example comes with an explanation, and most of them run.

• 22 sections: simple types, arrays and collections, classes, interfaces and generics, functions and lambdas, files, serialization, exceptions, regular expressions, threading, databases, patterns.
• Run in the app: the example really executes and the output appears under the code. Needs an internet connection; the daily limit is 30 launches.
• What changed in new versions: 8 sections from Java 9 to 21, with "before" and "after" code side by side.
• Keyword and function reference: 160 articles - browse the list or search by word.
• SQL alongside: over 200 queries against a live practice database - JOIN, GROUP BY, subqueries, data types. Queries have their own daily count.
• Edit examples and add your own - they stay in the app and are always at hand.
• Search runs over the code itself, not just the titles: remember a fragment and you will find the example.
• Everything except running works offline: examples, search, favourites.
• Comfortable to read: light and dark themes, your own font and size, line numbers, and long lines wrap instead of running off the screen.

Examples are drawn from professional sources and verified by running them.

Made by a developer for developers. In development since 2015.