fork download
copy 
  1. import java.util.*;
  2. import java.util.stream.*;
  3.  
  4. class Shop {
  5.  
  6.     public static void main(String[] args) {
  7.         List<Shop> shops = Arrays.asList(
  8.             new Shop("Walmart", "Hammer", 100),
  9.             new Shop("Target", "Scissor", 30),
  10.             new Shop("Walgreens", "Hammer", 300),
  11.             new Shop("Glens", "Hammer", 500),
  12.             new Shop("Walmart", "Scissor", 75),
  13.             new Shop("Toms", "Hammer", 150)
  14.         );
  15.  
  16.         Map<String, List<Shop>> result = shops.stream()
  17.             .collect(Collectors.groupingBy(Shop::item, Collectors.collectingAndThen(Collectors.toList(), list -> {
  18.                 Collections.sort(list, Comparator.comparing((Shop shop) -> shop.size()).reversed());
  19.                 return list.subList(0, Math.min(3, list.size()));
  20.             })));
  21.         result.forEach((k, v) -> {
  22.             System.out.println(k);
  23.             v.forEach(subshop -> System.out.println("  - " + subshop));
  24.         });
  25.     }
  26.  
  27.     String name;
  28.     String item;
  29.     int size;
  30.  
  31.     Shop(String name, String item, int size) {
  32.         this.name = name;
  33.         this.item = item;
  34.         this.size = size;
  35.     }
  36.  
  37.     String name() {
  38.         return name;
  39.     }
  40.  
  41.     String item() {
  42.         return item;
  43.     }
  44.  
  45.     int size() {
  46.         return size;
  47.     }
  48.  
  49.  
  50.     @Override
  51.     public String toString() {
  52.         return String.format("Shop(name=%s, item=%s, size=%s)", name, item, size);
  53.     }
  54. }
Success #stdin #stdout 0.13s 55192KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
Hammer
  - Shop(name=Glens, item=Hammer, size=500)
  - Shop(name=Walgreens, item=Hammer, size=300)
  - Shop(name=Toms, item=Hammer, size=150)
Scissor
  - Shop(name=Walmart, item=Scissor, size=75)
  - Shop(name=Target, item=Scissor, size=30)
https://ideone.com/qUl2BS
language:
Java (HotSpot 12)
created:
4 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!