Showcases a compiler bug in the JDK 8_20

App.java

class App {
  interface B<T>{T get();}
  interface C<S>{}	

  static void error() {
    C a = null;

    /* 
     * No error, but an Error with Java 7(which is correct). 
     * Foo returns a Rawtype which gets mapped to B<Float>
     */
    B<Float> b = foo(a); 

    /* 
     * compile error: 
     * incompatible types: Object cannot be converted to String
     * 
     * This wrong error exists, because the compiler thinks that foo returns the Rawtype B
     */
    String c = foo(a).get();
  }

  /*
   * if a is a Rawtype the compiler wrongly assumes, that the return type is also a Rawtype.
   */
  static B<String> foo(C<Integer> a) {
    return null;
  }

  static void working() {
    C<Integer> a = null;
    /* 
     * No error, the compiler is correct, that foo returns the parametized type B<String>
     */
    String c = foo(a).get();
  }
}