Difference between an unbound wildcard and a raw type
I was reading about generics and I did not understand the need for unbound wildcards and how it differs from raw type. I read this question but still did not get it clearly.
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How
Listdiffers fromListThe main difference is that the first line compiles but the second does not:
List list = new ArrayList(); List However, because you don't know what the generic type of
Listis, you can't use its parameterized methods:List list = new ArrayList(); list.add("aString"); //does not compile - we don't know it is a List list.clear(); //this is fine, does not depend on the generic parameter type As for the difference with raw types (no generics), the code below compiles and runs fine:
List list = new ArrayList(); list.add("aString"); list.add(10);
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