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What is the purpose of `NavigableMap` interface in Java?

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What is the difference between `String.format()` and `String.formatted()` (Java 15+)?

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What does `Class.forName()` do in Java reflection?

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What does `CompletableFuture.thenCompose()` do differently from `thenApply()`?

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What is the purpose of `@Retention` in a custom annotation?

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What is the output of the following? “`java Stream.of(1, 2, 3).reduce(0, Integer::sum) “`

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What is `StampedLock` in Java and how does it differ from `ReadWriteLock`?

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What does `Map.computeIfAbsent()` do?

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What distinguishes a daemon thread from a non-daemon thread in Java?

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What is the purpose of `Phaser` in Java concurrency?

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What is the difference between `CopyOnWriteArrayList` and `ArrayList`?

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What does the PECS principle stand for in Java generics?

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In Java generics, what does `? extends T` mean?

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What happens when you call `stream.forEach()` on a parallel stream?

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What is the purpose of `Collectors.teeing()` introduced in Java 12?

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What is the difference between `Predicate.and()` and `Predicate.or()` in Java streams?

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What does `Enum.values()` return?

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Which functional interface represents a function that takes no arguments and returns a value?

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