Learning paths

Java 8 and collections, practically

Lambdas and the core functional interfaces with real examples, every List, Set, Map and Queue, streams, and the comparisons interviewers love.

  • For: You can write basic Java and want to use lambdas and collections the way professionals do.
  • By the end: You pick the right collection without thinking twice and write clean, modern Java with lambdas and streams.
  • Size: 16 lessons (51 min of reading, plus time to try the code), intermediate
Start with Lambdas and functional interfaces
  1. Collections framework: choosing the right oneCore APIs, intermediate, 3 min
  2. Every List, Set and Queue: ArrayList to BlockingQueueCore APIs, intermediate, 4 min
  3. Every Map: HashMap, LinkedHashMap, TreeMap, Hashtable and ConcurrentHashMapCore APIs, intermediate, 3 min
  4. Sorting objects: Comparable and ComparatorCore APIs, intermediate, 3 min
  5. Stream APIModern Java, intermediate, 3 min
  6. Collectors: grouping, partitioning and joiningModern Java, intermediate, 3 min
  7. Optional: handling absenceModern Java, intermediate, 3 min
  8. ArrayList vs LinkedListCollections compared, intermediate, 3 min
  9. HashSet vs TreeSet (and LinkedHashSet)Collections compared, intermediate, 3 min
  10. HashMap vs HashtableCollections compared, intermediate, 3 min
  11. HashMap vs ConcurrentHashMapCollections compared, advanced, 3 min
  12. HashMap vs LinkedHashMapCollections compared, intermediate, 3 min
  13. Comparable vs ComparatorCollections compared, intermediate, 3 min
  14. Iterator vs ListIteratorCollections compared, intermediate, 3 min
  15. Fail-fast vs fail-safe iteratorsCollections compared, intermediate, 3 min

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