Java Utililty Methods Map Reverse

List of utility methods to do Map Reverse

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Description

The list of methods to do Map Reverse are organized into topic(s).

Method

MapsortByValue(Map map, boolean reverse)
sort By Value 
List list = new LinkedList(map.entrySet());
Collections.sort(list, new Comparator() {
    @Override
    public int compare(Object o1, Object o2) {
        return ((Comparable) ((Map.Entry) (o1)).getValue()).compareTo(((Map.Entry) (o2)).getValue());
});
if (reverse) {
...
MapsortByValue(Map map, boolean doReverse)
Sorts a map based on value, returns sorted map with predictable iteration Initial code from: http://stackoverflow.com/questions/109383/how-to-sort-a-mapkey-value-on-the-values-in-java 
List<Map.Entry<K, V>> list = new LinkedList<Map.Entry<K, V>>(map.entrySet());
Comparator<Map.Entry<K, V>> comparator = 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());
};
if (doReverse) {
    Collections.sort(list, Collections.reverseOrder(comparator));
...
Map>toReverseIndex(Map> forwardIndex)
to Reverse Index 
Map<String, Map<Integer, String>> reverseForwardIndex = new HashMap<String, Map<Integer, String>>();
for (String dimensionName : forwardIndex.keySet()) {
    Map<String, Integer> map = forwardIndex.get(dimensionName);
    reverseForwardIndex.put(dimensionName, new HashMap<Integer, String>());
    for (Entry<String, Integer> entry : map.entrySet()) {
        reverseForwardIndex.get(dimensionName).put(entry.getValue(), entry.getKey());
return reverseForwardIndex;