This question already has an answer here:
Sort a Map by Key or by value in java
Input Map 1-eee 4-ddd 5-ccc 0-bbb 3-aaa
1st Output Map(By-Key): 0-bbb 1-eee 3-aaa 4-ddd 5-ccc
2nd Output Map(By-Value): 3-aaa 0-bbb 5-ccc 4-ddd 1-eee
This code will first sort the map by Key and then by value.
Just write a main method and call this method as follow:
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
public class SortMapByKeyAndValue
{
public static void main(String[] args)
{
aMapSortProgramByKeyAndValue();
}
private static void aMapSortProgramByKeyAndValue()
{
Map<String, Integer> myMap = new HashMap<String, Integer>();
// putting values in the Map
myMap.put("Jayant", 80);
myMap.put("Abhishek", 90);
myMap.put("Anushka", 80);
myMap.put("Amit", 75);
myMap.put("Spandan", 50);
myMap.put("Hari", 55);
myMap.put("Keshav", 60);
System.out.println("Map data without Sort :-");
for (Entry<String, Integer> myEntryMapData : myMap.entrySet())
{
System.out.println("The Map data is Key: " + myEntryMapData.getKey() + " Value: "
+ myEntryMapData.getValue());
}
List<Entry<String, Integer>> myMapDataAsList = new ArrayList<Map.Entry<String, Integer>>();
myMapDataAsList.addAll(myMap.entrySet());
System.out.println("Map data Stored in List, The whole List is : " + myMapDataAsList);
Iterator<Entry<String, Integer>> myListIterator = myMapDataAsList.iterator();
System.out.println("Map data Stored in List, Print through iterator :-");
for (; myListIterator.hasNext();)
{
Entry<String, Integer> myListData = myListIterator.next();
System.out.println("The List data is Key: " + myListData.getKey() + " Value: " + myListData.getValue());
}
Collections.sort(myMapDataAsList, new Comparator<Entry<String, Integer>>()
{
@Override
public int compare(Entry<String, Integer> dataOne, Entry<String, Integer> dataTwo)
{
return dataOne.getKey().compareTo(dataTwo.getKey());
}
});
System.out.println("After Sort by the Key the Map data is : ");
myListIterator = myMapDataAsList.iterator();
for (; myListIterator.hasNext();)
{
Entry<String, Integer> myListData = myListIterator.next();
System.out.println("The List data is Key: " + myListData.getKey() + " Value: " + myListData.getValue());
}
Collections.sort(myMapDataAsList, new Comparator<Entry<String, Integer>>()
{
@Override
public int compare(Entry<String, Integer> dataOne, Entry<String, Integer> dataTwo)
{
return dataOne.getValue().compareTo(dataTwo.getValue());
}
});
System.out.println("After Sort by the vale the Map data is : ");
myListIterator = myMapDataAsList.iterator();
for (; myListIterator.hasNext();)
{
Entry<String, Integer> myListData = myListIterator.next();
System.out.println("The List data is Key: " + myListData.getKey() + " Value: " + myListData.getValue());
}
}
}
import java.util.Collections;
import java.util.Comparator;
import java.util.LinkedHashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
public class MapSortUtil
{
public static Map<String, String> sortMapByKey(Map<String, String> anUnSortedMap)
{
List<Entry<String, String>> myListOfEntrySet = getListOfEntrySetFromMap(anUnSortedMap);
/* Sort the list of entry-set in ascending order. */
Collections.sort(myListOfEntrySet, new MapComparatorToSortByKey());
/* Generating new Map from Sorted Entry List. */
Map<String, String> mySortedMap = getSortedMapFromSortedEntry(myListOfEntrySet);
return mySortedMap;
}
public static Map<String, String> sortMapByValue(Map<String, String> anUnSortedMap)
{
List<Entry<String, String>> myListOfEntrySet = getListOfEntrySetFromMap(anUnSortedMap);
/* Sort the list of entry-set in ascending order. */
Collections.sort(myListOfEntrySet, new MapComparatorToSortByValue());
/* Generating new Map from Sorted Entry List. */
Map<String, String> mySortedMap = getSortedMapFromSortedEntry(myListOfEntrySet);
return mySortedMap;
}
private static List<Entry<String, String>> getListOfEntrySetFromMap(Map<String, String> anUnSortedMap)
{
/* Getting Entry Set from the Map. */
Set<Entry<String, String>> myEntrySetOfMap = anUnSortedMap.entrySet();
/* Creating List of Entry Set. */
List<Entry<String, String>> myListOfEntrySet = new LinkedList<Map.Entry<String, String>>(myEntrySetOfMap);
return myListOfEntrySet;
}
private static Map<String, String> getSortedMapFromSortedEntry(List<Entry<String, String>> myListOfEntrySetOfMap)
{
/* Add Sorted list in new LinkedHashMap one-by-one. */
Map<String, String> mySortedLinkedHashMap = new LinkedHashMap<String, String>();
for (Entry<String, String> myOneByOneData : myListOfEntrySetOfMap)
{
mySortedLinkedHashMap.put(myOneByOneData.getKey(), myOneByOneData.getValue());
}
return mySortedLinkedHashMap;
}
}
class MapComparatorToSortByValue implements Comparator<Entry<String, String>>
{
@Override
public int compare(Entry<String, String> aMap1, Entry<String, String> aMap2)
{
return aMap1.getValue().compareTo(aMap2.getValue());
}
}
class MapComparatorToSortByKey implements Comparator<Entry<String, String>>
{
@Override
public int compare(Entry<String, String> aMap1, Entry<String, String> aMap2)
{
return aMap1.getKey().compareTo(aMap2.getKey());
}
}
