JDK-8144832 : cast conversion fails when converting a type-variable to primitive type
  • Type: Bug
  • Component: tools
  • Sub-Component: javac
  • Affected Version: 7u85,8,9
  • Priority: P3
  • Status: Closed
  • Resolution: Fixed
  • Submitted: 2015-12-07
  • Updated: 2017-01-05
  • Resolved: 2015-12-16
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JDK 9
9 b99Fixed
Related Reports
Duplicate :  
JDK-8168269 - Javac compile error on cast to primitive when using generics wirldcards
Duplicate :  
JDK-8151591 - Object can be cast to primitive
Description
The following program is erroneously rejected by javac:

class Test<T> {
    public void foo(T valIn){
        double val = (double ) valIn;
    }
}
Comments
Another test case, from JDK-8168269, this time using capture variables: public static void main(String... s) { List<?> l = Arrays.asList(1, 2, 3, 4); if (l.get(0) instanceof Integer) { System.out.println((int) l.get(0)); } }
05-01-2017