Weird usage of Java Generics compiles correctly with JDT (and code runs) but does not compile with Oracle's Java6 compiler

[Danilo Tommasina]

Hi Maurizio

Many thanks for the quick reply.
Best Regards
Danilo

On 02/21/2012 02:32 PM, Maurizio Cimadamore wrote:
> Hi
> These failures are caused by the fact that JDK 6 compiler doesn't 
> implement type-inference correctly. A lot of effort has been put into 
> JDK 7 compiler in order to get rid of all these problems (your program 
> compiles fine in JDK 7). However, some of those inference improvements 
> require source incompatible changes, which is why we cannot backport 
> these fixes in the JDK 6 release.
>
> Maurizio
>
> On 21/02/12 12:43, Danilo Tommasina wrote:
>> |class  MyWeirdClass  {
>>
>>      public  void  entryPoint()  {
>>          doSomethingWeird();
>>      }
>>
>>      @SuppressWarnings(  "unchecked"  )
>>      private  <Textends  A&  B>  T getMyClass()  {
>>          if  (  System.currentTimeMillis()  %  2  ==  0  )  {
>>             return  (T)  new  MyClass_1();
>>          }  else  {
>>             return  (T)  new  MyClass_2();
>>          }
>>      }
>>
>>      private  <Textends  A&  B>  void  doSomethingWeird()  {
>>          T obj=  getMyClass();
>>
>>          obj.methodFromA();
>>          obj.methodFromB();
>>      }
>>
>>      static  interface A{
>>          void  methodFromA();
>>      }
>>
>>      static  interface B{
>>          void  methodFromB();
>>      }
>>
>>      static  class  MyClass_1  implements  A,  B{
>>          public  void  methodFromA()  {};
>>          public  void  methodFromB()  {};
>>      }
>>
>>      static  class  MyClass_2  implements  A,  B{
>>          public  void  methodFromA()  {};
>>          public  void  methodFromB()  {};
>>      }
>> }
>> |
>
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