java map value sort

import java.util.*;

public class MapUtil
{
    public static <K, V extends Comparable<? super V>> Map<K, V> 
        sortByValue( Map<K, V> map )
    {
        List<Map.Entry<K, V>> list =
            new LinkedList<Map.Entry<K, V>>( map.entrySet() );
        Collections.sort( list, new Comparator<Map.Entry<K, V>>()
        {
            public int compare( Map.Entry<K, V> o1, Map.Entry<K, V> o2 )
            {
                return (o1.getValue()).compareTo( o2.getValue() );
            }
        } );

        Map<K, V> result = new LinkedHashMap<K, V>();
        for (Map.Entry<K, V> entry : list)
        {
            result.put( entry.getKey(), entry.getValue() );
        }
        return result;
    }
}

And an associated JUnit4 test so you don't have to take my word for it:

import java.util.*;
import org.junit.*;

public class MapUtilTest
{
    @Test
    public void testSortByValue()
    {
        Random random = new Random(System.currentTimeMillis());
        Map<String, Integer> testMap = new HashMap<String, Integer>(1000);
        for(int i = 0 ; i < 1000 ; ++i) {
            testMap.put( "SomeString" + random.nextInt(), random.nextInt());
        }

        testMap = MapUtil.sortByValue( testMap );
        Assert.assertEquals( 1000, testMap.size() );

        Integer previous = null;
        for(Map.Entry<String, Integer> entry : testMap.entrySet()) {
            Assert.assertNotNull( entry.getValue() );
            if (previous != null) {
                Assert.assertTrue( entry.getValue() >= previous );
            }
            previous = entry.getValue();
        }
    }

}

Java 7 Version

public static <K, V extends Comparable<? super V>> Map<K, V> 
    sortByValue( Map<K, V> map )
{
    List<Map.Entry<K, V>> list =
        new LinkedList<>( map.entrySet() );
    Collections.sort( list, new Comparator<Map.Entry<K, V>>()
    {
        @Override
        public int compare( Map.Entry<K, V> o1, Map.Entry<K, V> o2 )
        {
            return (o1.getValue()).compareTo( o2.getValue() );
        }
    } );

    Map<K, V> result = new LinkedHashMap<>();
    for (Map.Entry<K, V> entry : list)
    {
        result.put( entry.getKey(), entry.getValue() );
    }
    return result;
}

Java 8 Version

public static <K, V extends Comparable<? super V>> Map<K, V> 
    sortByValue( Map<K, V> map )
{
      Map<K,V> result = new LinkedHashMap<>();
     Stream <Entry<K,V>> st = map.entrySet().stream();

     st.sorted(Comparator.comparing(e -> e.getValue()))
          .forEachOrdered(e ->result.put(e.getKey(),e.getValue()));

     return result;
}