Java将数组传递给泛型方法

Question

I have this generic method:

public <T> T get(Class<T> type, String... keys)
{
    String key = String.join(".", keys);
    if(this._data.containsKey(key))
        return type.cast(this._data.get(key));

    return null;
}

and I need to pass a generic Array as type but I don't understand how to do it:

public <T extends SearchableItem> ArrayList<T> filterAudio(T[] type, int taxonomyId, TaxonomyLevel level, int count) {
    T[] all = (T[])masterDbManager.get(type, "audiotracks-alphabetic");
    ....
}

But that doesn't work because the get() method wants a class:

Error:(200, 39) java: method get in class com.xxxxxx.yyyyy.dal.MasterDbManager cannot be applied to given types; required: java.lang.Class,java.lang.String[] found: T[],java.lang.String reason: cannot infer type-variable(s) T (argument mismatch; T[] cannot be converted to java.lang.Class)

not an Array, so how can I use the get() method when I need to retrieve an Array?

Hope my request is clear :)

EDIT : ok I needed the .getClass() method

T[] all = (T[])masterDbManager.get(type.getClass(), dbKey);

BUT how do I now call the filterAudio() method from the following method?

public <T> ArrayList<T> searchAudio(Class<T> type, int taxonomyId, TaxonomyLevel taxonomyLevel, String searchText, int page, int pageSize, SearchOrder order) {
    ArrayList<T> all = filterAudio(???, taxonomyId, taxonomyLevel, 0);
    ...
}

Answer 1

In your specific case you can simply write (T[])masterDbManager.get(Object.class, "audiotracks-alphabetic") because you cast result to T[] anyway.

In general there is no Class corresponding to T[] type. It will by always Array.class no matter what base type array have.

Answer 2

you have to pass exact type to get method. If your type is array then you will need to pass something like String[].class - according to the signature provided