Convert List Array into Map

Question

I am trying to make a Hashmap out of a List of Objects[] but I am unable to do so. Below is the code that I have written:

List<Object[]> adjustments =  query.getResultList();
Map<Integer, BigDecimal> dpaMap = adjustments.stream().collect(Collectors.toMap(a -> (Integer)a[0], a -> (BigDecimal)a[1]));

I know that only two fields are returning from the query they have the same Type as mentioned in Map, but its not working. Please guide me in this regard.

Thanks In Advance.

Possible duplicate of [Java: How to convert List to Map](http://stackoverflow.com/questions/4138364/java-how-to-convert-list-to-map) — Sanka, Oct 27 '16 at 09:28
Your code works fine to me (when the `Object[]` arrays contain what you say they do). I tried : `List — Eran, Oct 27 '16 at 09:30
@Eran When I am debugging the code, it doesn't recognize a[0] and a[1] and when the 2nd line executes, it throws an exception — Muhammad Umer, Oct 27 '16 at 09:32

score 6 · Accepted Answer · answered Oct 27 '16 at 09:45

So it seems that it was working fine, the column in the DB was returning Float so just had to cast it to BigDecimal

Map<Integer, BigDecimal> dpaMap = adjustments.stream().collect(Collectors.toMap(a -> (Integer)a[0], a -> BigDecimal.valueOf((Float) a[1])));

Thanks a lot people for your help.

Convert List Array into Map

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