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Thread: Maps Question

  1. #1
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    Default Maps Question

    I have an odd sort of question. Let's say I have two Maps (map1 and map2) where:
    map1: Map<String,Object>
    map2: Map<Object,Integer>

    map2's keys can only consist of map1's values.

    My end goal is to print out the Integer from map2, which represents the value mapped to the key from map1.

    For example, let's say map1's keys and values looked like:
    "str1", obj1
    "str5", obj2
    "str2", obj4
    and map2's keys and values looked like:
    obj2, 3
    obj1, 2
    obj4, 6
    In the end, I am wanting to print out something like:
    "str1" = 2
    "str5" = 3
    "str2" = 6
    Does anyone have any ideas how to go about doing this? I'm restricted to the Map Interface methods (as it is unknown to me which implementing class was used to make the Map).
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  2. #2
    Super Moderator copeg's Avatar
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    Default Re: Maps Question

    If I understand the question correctly, can you just cascade the gets?
    map2.get(map1.get("str1"));

  3. #3
    Super Moderator Norm's Avatar
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    Default Re: Maps Question

    What methods have you tried? Look at the methods available and see which ones get the values you want.
    If you don't understand my answer, don't ignore it, ask a question.

  4. #4
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    Default Re: Maps Question

    I might have figured it out. I did sort of what copeg suggested. The only problem is that I don't know the keys for map1. But I managed to get those keys by calling the Map.keySet() method, and then the Set.toArray() method. I have no idea if it worked, but I will know when the rest of the code is put together and I can test it.
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  5. #5
    Super Moderator Norm's Avatar
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    Default Re: Maps Question

    You should be able to test it with a small testing program.
    If you don't understand my answer, don't ignore it, ask a question.

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