使用 lambda 和流按值对地图进行排序

Sort map by value using lambdas and streams(使用 lambda 和流按值对地图进行排序)

问题描述

I'm new to Java 8, not sure how to use streams and it's methods to sort. If I have map as below, how to sort this map by value to take only top 10 entries using Java 8.

HashMap<String, Integer> map = new HashMap<String, Integer>();
        map.put("a", 10);
        map.put("b", 30);
        map.put("c", 50);
        map.put("d", 40);
        map.put("e", 100);
        map.put("f", 60);
        map.put("g", 110);
        map.put("h", 50);
        map.put("i", 90);
        map.put("k", 70);
        map.put("L", 80);

I know before Java 8, we can sort as this link: https://stackoverflow.com/a/109389/4315608

You can always start reading the documentation and some tutorials.

map.entrySet().stream()
        .sorted(Map.Entry.<String, Integer>comparingByValue().reversed()) 
        .limit(10) 
        .forEach(System.out::println); // or any other terminal method

Reference

http://www.leveluplunch.com/java/examples/sort-order-map-by-values/

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