Java 8 Streams - Collectors.summarizingInt Examples

The static method, Collectors.summarizingInt() returns a Collector which applies a mapping function to each input element of type T to convert it to primitive int, and returns summary statistics for the resulting integer values.


<T> Collector<T,?,IntSummaryStatistics> summarizingInt(ToIntFunction<? super T> mapper)

Examples

package com.logicbig.example.collectors;

import java.math.BigDecimal;
import java.util.IntSummaryStatistics;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;

public class SummarizingIntExample {
    public static void main (String[] args) {
        Stream<BigDecimal> s = Stream.iterate(
                            BigDecimal.ONE, bigDecimal ->
                                      bigDecimal.add(BigDecimal.ONE))
                                       .limit(10).peek(System.out::println);

        IntSummaryStatistics i = s.collect(Collectors.summarizingInt
                                                        (BigDecimal::intValue));
        System.out.println(i);
    }
}

Output

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IntSummaryStatistics{count=10, sum=55, min=1, average=5.500000, max=10}

Original Post

Java 8 Streams - Collectors.summarizingInt Examples

Examples

Output

See Also