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Oracle Certified Professional: Java SE Developer 1Z0-831 (Java SE 25) · Domain 6: Working with streams and lambda expressions

Primitive streams and summary statistics

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Last reviewed September 25, 2026 · Leer en español

Java has three primitive stream types: IntStream, LongStream and DoubleStream. They exist to avoid the cost of boxing each number into an Integer, Long or Double object, and they add numeric operations that Stream<T> lacks, such as sum(), average() and summaryStatistics(). There is no CharStream, ByteStream or FloatStream; String.chars() returns an IntStream.

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