java - Is it OK to use a HashMap to keep indices of list elements? -


i have list of objects.

list<myobject> mylist;

this list populated in beginning , no update done after that.

the order of objects in list significant because need iterate on list in order later.

during execution of program, need find index of given myobject in mylist;

i know can use mylist.indexof(object) worried performance. going use hashmap map each myobject in mylist index in mylist can find index efficiently.

but not sure whether missing trivial , going use 2 containers redundant data done using different container.

so, can see better way this?

you can use linkedhashmap contain myobject instances.

map<string, myobject> map = new linkedhashmap<string, myobject>();

hash table , linked list implementation of map interface, predictable iteration order.

this allow have 1 collection both.


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