TreeMap<int[],Double> initialisation and sorting by value

Question

I have to make sorted map which key is int[] and value is double. It cant be swapped because double will be duplicated. Moreover, map will be sort by value and last x values will be deleted.

I tried to make

Map<int[],Double> map = new TreeMap<>();;
int[] i = {0,1,1,0};  
    map.put(i,8.5);  // ERROR HERE Organisms.java:46
    i = new int[]{0,0,0,0};
    map.put(i,30.0);
    System.out.println("sorted" + sortByValue(map));

Exception in thread "AWT-EventQueue-0" java.lang.ClassCastException: [I cannot be cast to java.lang.Comparable at java.util.TreeMap.compare(TreeMap.java:1294) at java.util.TreeMap.put(TreeMap.java:538) at com.pszt_organism.Organisms.test(Organisms.java:46) <-- MARKED ERROR

I found method sortByValue(Map<K, V> map) in this topic: java8 example by Carter Page

I suppose that TreeMap has problem with sorting table of int. How to solve that?

EDIT:

private  <K, V extends Comparable<? super V>> Map<K, V> sortByValue(Map<K, V> map) {
        return map.entrySet()
                .stream()
                .sorted(Map.Entry.comparingByValue(/*Collections.reverseOrder()*/))
                .collect(Collectors.toMap(
                        Map.Entry::getKey,
                        Map.Entry::getValue,
                        (e1, e2) -> e1,
                        LinkedHashMap::new
                ));
    }

Answer 1

You don't need to use TreeMap to use that sorting method. Just use a different Map. That sorting method creates a new LinkedHashMap for the result, so the Map which is passed as an argument is just a temporary container.