Reviewed by Aditya Kumar · Last reviewed 2026-03-24
**Java 8 (March 2014):** Lambda expressions + Stream API. Syntax: (params) -> expr or (params) -> { stmts }. Implement functional interfaces (single abstract method). **Use Cases:** Callbacks, Comparator, forEach, Stream map/filter/reduce. Enables concise, readable code....
Java 8 (March 2014): Lambda expressions + Stream API. Syntax: (params) -> expr or (params) -> { stmts }. Implement functional interfaces (single abstract method).
Use Cases: Callbacks, Comparator, forEach, Stream map/filter/reduce. Enables concise, readable code. Spark's Java API uses lambdas in map, filter, reduce.
Compatibility: Spark requires Java 8+. For JP Morgan legacy systems: ensure Java 8+ for Spark/streaming stacks.
list.forEach(x -> print(x));
Comparator<String> c = (a,b) -> a.length() - b.length();
Red Flag: Not knowing Java 8 is minimum for Spark. Pro-Move: 'We use lambdas in our Spark mapPartitions—cleaner than anonymous classes.'
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