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Thread: Change HashMap Type

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    Default Change HashMap Type

    I was wondering is it posible to change the Type of a HashMap?

    Becasue lets say I have used an Api (Apache POI) to create a HashMap.
    Map<Cell, XSSFCell> mapFile1 = new LinkedHashMap<Cell, XSSFCell>();

    But later on in the program I work with a lot of strings, and I would like to be able to look a string up in the HashMap.
    Is there a way to make the same HashMap:

    Map<String, String> mapFile1 = new LinkedHashMap<String, String>();


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    Default Re: Change HashMap Type

    Why do you need to use the same variable name? When you define a variable, the compiler saves its type for use later in the program. To have two variables with the same name but different types, you would need to define them in different scopes.
    If you don't understand my answer, don't ignore it, ask a question.

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    Default Re: Change HashMap Type

    So it would be possibel to covert the data from:

    Map<Cell, XSSFCell> mapFile1 = new LinkedHashMap<Cell, XSSFCell>();

    to

    Map<String, String> mapFile1String = new LinkedHashMap<String, String>();

    Becasue I find it very hard to work with this HashMap: Map<Cell, XSSFCell> mapFile1 = new LinkedHashMap<Cell, XSSFCell>();

    I can't even get the keys out there properly.

    Like .containsKey() won't even work on that HashMap.

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    Default Re: Change HashMap Type

    Do the Cell class and the XSSFCell class have methods that will convert their contents to a useful String?
    If so loop through the keys of the first Map, get the value for each key, convert the key and value to String and put them into the second Map.
    If you don't understand my answer, don't ignore it, ask a question.

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