Sorting the TreeMap

Question

I am trying to sort a TreeMap based on Values like this:-
public class SortedValueTest
public static void main( String[] args )
Map map = new TreeMap();
map.put( "field1", new Integer( 0 ) );
map.put( "field2", new Integer( 2 ) );
map.put( "field3", new Integer( 2 ) );
map.put( "field4", new Integer( 0 ) );
Set set = new TreeSet(
new Comparator()
public int compare( Object o1, Object o2 )
Map.Entry e1 = (Map.Entry)o1;
Map.Entry e2 = (Map.Entry)o2;
Integer d1 = (Integer)e1.getValue();
Integer d2 = (Integer)e2.getValue();
return d1.compareTo( d2 );
set.addAll( map.entrySet() );
for ( Iterator iter = set.iterator(); iter.hasNext(); )
Map.Entry entry = (Map.Entry)iter.next();
System.out.println( entry.getKey() + " = " + entry.getValue() );
The output obtained is like this:-
field1 = 0
field2 = 2
But the required output should not omit the duplicate items.
So the above solution based on TreeSet does not seems to be applicable.
Is there any alternative way to solve this problem?
Thanks in Advance.

Answer 1

SOLVED!!!
import java.io.IOException;
import java.util.*;
* Created by IntelliJ IDEA.
* User: ponmanadiyilv
* Date: 06-Mar-2006
* Time: 11:46:29
* To change this template use File | Settings | File Templates.
public class GoodSort {
public static void main(String[] args) throws Exception {
Map m = new HashMap();
m.put ("field1", new Integer(12));
m.put ("field2", new Integer(2));
m.put ("field3", new Integer(30));
m.put ("field4", new Integer(5555));
m.put ("field5", new Integer(0));
m.put ("field6", new Integer(5555));
ArrayList outputList = sortMap(m);
int count = 0;
count = outputList.size();
while(count > 0) {
Map.Entry entry = (Map.Entry) outputList.get(--count);
System.out.print("Key:" + entry.getKey());
System.out.println("\tValue:" + entry.getValue());
* This method will use Arrays.sort for sorting Map
* @param map
* @return outputList of Map.Entries
public static ArrayList sortMap(Map map) {
ArrayList outputList = null;
int count = 0;
Set set = null;
Map.Entry[] entries = null;
// Logic:
// get a set from Map
// Build a Map.Entry[] from set
// Sort the list using Arrays.sort
// Add the sorted Map.Entries into arrayList and return
set = (Set) map.entrySet();
Iterator iterator = set.iterator();
entries = new Map.Entry[set.size()];
while(iterator.hasNext()) {
entries[count++] = (Map.Entry) iterator.next();
// Sort the entries with your own comparator for the values:
Arrays.sort(entries, new Comparator() {
public int compareTo(Object lhs, Object rhs) {
Map.Entry le = (Map.Entry)lhs;
Map.Entry re = (Map.Entry)rhs;
return ((Comparable)le.getValue()).compareTo((Comparable)re.getValue());
public int compare(Object lhs, Object rhs) {
Map.Entry le = (Map.Entry)lhs;
Map.Entry re = (Map.Entry)rhs;
return ((Comparable)le.getValue()).compareTo((Comparable)re.getValue());
outputList = new ArrayList();
for(int i = 0; i < entries.length; i++) {
outputList.add(entries);
return outputList;
}//End of sortMap