Loading…
46+ curated questions with the same answer shape every time: quick recap, deep dive, pitfalls, and follow-ups. Coverage includes lambdas functional interfaces, streams api, optional api, java 9 to 11 features, and more.
Suggested path
Topics follow a teaching order. Each answer ends with a clear Next question control so you can move forward without hunting the list.
Streams and modern Java features interviews test whether you use the functional style fluently. This module is an elevation arc: it opens with lambdas and functional interfaces (the foundation — SAM, method references), then the Streams API (the centerpiece — lazy, short-circuiting, collectors), then Optional (the null-handling companion). From there it moves through Java version features (9-11, 14-17, 21) in release order so a learner sees the language evolve. It closes with comparisons and scenario-based questions.
Full catalog
Topics are ordered for learning. Within each topic, rows are numbered 1–46 globally so you always know where you are. Collapse topics if you want a lighter view — use Expand all when you need the full list again.
Numbers 1–46 follow the order we recommend — click any row to open the full answer, or use the sticky Next link at the bottom of each page to go Q1 → Q46.
Interviewers rarely ask Java Streams, Lambdas & Modern Java in isolation. These are the modules that most often come up in the same loop.