Java HashMap Sort sortByComparator(HashMap unsortMap, final boolean ascendingorder)

Description

sort By Comparator

License

Open Source License

Declaration

public static HashMap<String, Integer> sortByComparator(HashMap<String, Integer> unsortMap,
            final boolean ascendingorder) 

Method Source Code

//package com.java2s;
//License from project: Open Source License 

import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map.Entry;

public class Main {
    public static HashMap<String, Integer> sortByComparator(HashMap<String, Integer> unsortMap,
            final boolean ascendingorder) {

        List<Entry<String, Integer>> list = new LinkedList<Entry<String, Integer>>(unsortMap.entrySet());

        // Sorting the list based on values
        Collections.sort(list, new Comparator<Entry<String, Integer>>() {
            public int compare(Entry<String, Integer> o1, Entry<String, Integer> o2) {
                if (ascendingorder) {
                    return o1.getValue().compareTo(o2.getValue());
                } else {
                    return o2.getValue().compareTo(o1.getValue());

                }//from ww  w  . j  ava  2  s. c  o m
            }
        });

        // Maintaining insertion order with the help of LinkedList
        HashMap<String, Integer> sortedMap = new LinkedHashMap<String, Integer>();
        for (Entry<String, Integer> entry : list) {
            sortedMap.put(entry.getKey(), entry.getValue());
        }

        return sortedMap;
    }
}

Related

1. getSortedColors(HashMap colors)
2. getSortedHashMapKeyset(Map sorting)
3. getSortedLinkedHashMap(Map bitCounts, Comparator