generics - Fixing error in java: incompatible types: java.lang.Object cannot be converted to capture#1 of? -


my code declares value variable of type object:

final object value;

this variable loaded object.

a generic collection variable declared , loaded:

final collection<?> c = (collection<?>) argumentdefinition.getfieldvalue();

the collection variable generic in both instances above, brackets , question mark don't pass through in text.

when try use add method of collection:

c.add(value)

i error message:

java: incompatible types:java.lang.object cannot converted capture #1 of ?

the add method declared in collection as:

boolean add(e e);

how can fix error? think understand what's going on - compiler creates placeholder generic type object isn't compatible with. can't use raw type collection because i'm trying eliminate raw types in code. need use helper function, , if how exactly? thank you.

it's hard tell problem without knowing argumentdefinition.getfieldvalue() returns, possible solution change variable type collection<?> collection<object>.


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