HashMap and int as key

java hashmap
MrD picture MrD · Apr 22, 2013 · Viewed 192.1k times · Source

I am trying to build a HashMap which will have integer as keys and objects as values.

My syntax is:

HashMap<int, myObject> myMap = new HashMap<int, myObject>();

However, the error returned is - Syntax error on token "int", Dimensions expected after this token - I don't understand why I should add a dimension (ie: making the int into an array) since I only need to store a digit as key.

What could I do?

Thanks in advance! :)

Answer

gaborsch picture gaborsch · Apr 22, 2013

Use Integer instead.

HashMap<Integer, MyObject> myMap = new HashMap<Integer, MyObject>();

Java will automatically autobox your int primitive values to Integer objects.

Read more about autoboxing from Oracle Java documentations.

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