Preserve order by value when inserting to map

Question

I need preserve order by value. I wrote some piece of code, but it is not really optimal.

I have a class like this,

class MyClass extends SomeOtherClass {

    private Map<Object, Object> resMap= new HashMap<>();

    Object getRes(Object key) {
        return resMap.get(key);
    }

    void putRes(Object key, Object value) {
        resMap.put(key, value);
    }

I want EACH time when I am invoking putRes(Object value) preserve order by value. Something like if value (that I received as an input) > all other values in map then put it first, if the value is equals to some value in map, so put it after it.

Appreciate any help.

upd: I need sort by Value and not by key. upd: I need sort by calling some method getPriority() of value.

I need preserve order while put in map by VALUE. If you have solution, I would be happy to see it) — liotur, Dec 10 '18 at 07:42
How are you using the map after inserting values? Are you iterating over it? — ernest_k, Dec 10 '18 at 08:03

score 1 · Answer 1 · answered Dec 10 '18 at 07:44

1

You can take a look at the SortedMap:

A Map that further provides a total ordering on its keys. The map is ordered according to the natural ordering of its keys, or by a Comparator typically provided at sorted map creation time.

answered Dec 10 '18 at 07:44

npinti

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Preserve order by value when inserting to map

1 Answers1