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FULL PRODUCT VERSION : java version "1.7.0" Java(TM) SE Runtime Environment (build 1.7.0-b147) Java HotSpot(TM) 64-Bit Server VM (build 21.0-b17, mixed mode) ADDITIONAL OS VERSION INFORMATION : Microsoft Windows [Version 6.1.7601] A DESCRIPTION OF THE PROBLEM : Attempting to compile this statement results in a "Type mismatch" error: Class<List<String>> stringListType = List.class; The compiler error specifically states "cannot convert from Class<List> to Class<List<String>>". This is a distinctly false statement. The following adjustment compiles with warnings but no errors: Class<List<String>> stringListType = (Class<List<String>>) (Class<?>) List.class; The code runs correctly, because the generic types are not present in the bytecode. So in fact the compiler "can convert from Class<List> to Class<List<String>>". Type erasure causes all generic tokens on a variable declaration of type Class to be fully meaningless in regards to cast compatibility. Therefore, every possibly generic qualification of a variable declaration of type Class should be assignable from a class literal with a matching base type. For example, this statement should compile with no errors or warnings: Class<Complicated<Nested<Type<Parameters>>>> complicatedType = Complicated.class; The compiler can do this. It is correct and also quite useful. STEPS TO FOLLOW TO REPRODUCE THE PROBLEM : Attempt to compile the syntactically meaningful statement: Class<List<String>> stringListType = List.class; EXPECTED VERSUS ACTUAL BEHAVIOR : EXPECTED - The statement should compile with no errors. This statement can be compiled, violates no rules, and causes no problems. ACTUAL - The compiler reports "Type mismatch: cannot convert from Class<List> to Class<List<String>>" ERROR MESSAGES/STACK TRACES THAT OCCUR : Type mismatch: cannot convert from Class<List> to Class<List<String>> REPRODUCIBILITY : This bug can be reproduced always. CUSTOMER SUBMITTED WORKAROUND : Add a painfully cumbersome pair of casts to the statement: Class<List<String>> stringListType = (Class<List<String>>) (Class<?>) List.class;