Covers Java 25 LTS. Latest release: Java 27 (Sept 2026).
0 of 8 topics passedKnowledge progress
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- 1Generics0 of 8 answers · pass with 70% over your last 8
- 2Collections in depth (HashMap internals, equals and hashCode)
- 3Lambdas and streams
- 4Optional and functional interfaces
- 5Concurrency basics (threads, executors)
- 6I/O and NIO
- 7JDBC and persistence basics
- 8Testing (JUnit, Mockito) and modern Java (records, sealed classes)
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