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Getting the Class object of a generic type

 
Greenhorn
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Is it possible to get and store the type of a generic variable somehow like you can use the class literal String.class?



If the method is called as <String>, the variable c should contain String.class.
 
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It is not possible.
 
Sheriff
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And the reason is type erasure. Look it up.

Unfortunately, var.getClass() won't help you either, and the following example shows why:
Because of polymorphism and interfaces, you can never say that calling getClass() on a reference with type X will return Class<X>.
 
Marshal
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Welcome to JavaRanch

To elaborate on what Bear has told you: Java does generics by type erasure, so the actual type parameter <String> vanishes entirely at runtime. You can identify the type of one of the elements of a Collection, but that is not necessarily the same as the type of the actual type parameter.

Simpler tutorial here.
 
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