Streams: summarizingInt collects every statistic in one pass

IntSummaryStatistics gathers count, sum, min, average and max together instead of running several terminal operations over the same data.

Code

var latencies = List.of(120, 95, 310, 45, 180);

IntSummaryStatistics stats = latencies.stream()
        .collect(Collectors.summarizingInt(Integer::intValue));

System.out.println("count   = " + stats.getCount());
System.out.println("sum     = " + stats.getSum());
System.out.println("min     = " + stats.getMin());
System.out.println("average = " + stats.getAverage());
System.out.println("max     = " + stats.getMax());

Output

count   = 5
sum     = 750
min     = 45
average = 150.0
max     = 310

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Published 2026-07-30