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POSorting HashMap values in Java not giving back right order
 

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    <p>I am having some problem with sorting <code>HashMaps</code> with values in <code>Java</code>. My code is:</p> <pre><code> @SuppressWarnings("unchecked") Map&lt;String, Integer&gt; scores = ((HashMap&lt;String, Integer&gt;) prefs.get()); Map&lt;String, Integer&gt; sortedscores = sortByValues(scores); printMap(scores); System.out.println("=============="); printMap(sortedscores); </code></pre> <p>the prefs.get() returns a <code>Map&lt;String, ?&gt;</code> which I convert to <code>&lt;String, Integer &gt;</code></p> <p>The sorting function:</p> <pre><code>public static &lt;K, V extends Comparable&lt;V&gt;&gt; Map&lt;K, V&gt; sortByValues(final Map&lt;K, V&gt; map) { Comparator&lt;K&gt; valueComparator = new Comparator&lt;K&gt;() { public int compare(K k1, K k2) { int compare = map.get(k2).compareTo(map.get(k1)); if (compare == 0) return 1; else return compare; } }; Map&lt;K, V&gt; sortedByValues = new TreeMap&lt;K, V&gt;(valueComparator); sortedByValues.putAll(map); return new LinkedHashMap&lt;K,V&gt;(sortedByValues); } public static void printMap(Map&lt;String, Integer&gt; unsortMap){ for (Map.Entry entry : unsortMap.entrySet()) { System.out.println("Key : " + entry.getKey() + " Value : " + entry.getValue()); } } </code></pre> <p>The output is:</p> <pre><code>Key : John Doe Value : 1000 Key : balazs Value : 975 Key : Balazs Value : 900 Key : aladar Value : 975 Key : balazs2 Value : 975 Key : score Value : 1000 Key : house Value : 1037 ============== Key : balazs Value : 975 Key : aladar Value : 975 Key : balazs2 Value : 975 Key : Balazs Value : 900 Key : house Value : 1037 Key : John Doe Value : 1000 Key : score Value : 1000 </code></pre> <p>The first one is the unsorted, the second is sorted. My problem is that the second output is not in DESC order (by value)</p> <p>EDIT: If I create a hasmap myself it works fine:</p> <pre><code>Map&lt;String, Integer&gt; unsortMap = new HashMap&lt;String, Integer&gt;(); unsortMap.put("asd", 1); unsortMap.put("asd2r1", 5); unsortMap.put("house", 7); unsortMap.put("3", 124); unsortMap.put("7", 4); unsortMap.put("5", 6); unsortMap.put("6", 2); unsortMap.put("8", 0); </code></pre> <p>But if I try it with this: <code>Map&lt;String, Integer&gt; scores = ((HashMap&lt;String, Integer&gt;) prefs.get());</code> I get that wierd order.</p>
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    1. COok, what is the problem here?
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      1. USmidhunhk
    2. COThe value should be sorted DESC order, but it is 975,975,975,900,1037,1000,1000 that 1037 is not where it should be
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    3. COLooks like something wrong in the comparator if your sort order is messed up.
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