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Generic cannot be applied

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Hello,

I have got these interface structure

public interface IVariable<T>
{

     public T get();
     public void set(T v);
}

public interface IOperator<T>
{
      public IVariable<T> evaluate( IVariable<T> p );
}


and I implement this class

public class myOperator<T extends Number> implements Operator<T>
{
      public IVariable<T> evaluate( IVariable<T> p )
      {
           p.set( new Double(p.get().doubleValue() + 1) );  <<<
           return p;
      }
}

The line with <<< create an compiler error  and I need to cast the new Double to T, but I don't understand, why I must cast. The error message is "IVariable<T> cannot be applied". IMHO a Double inherit from Number and T extends a Number on myOperator class, so an explicit cast is not needed.

Can anybody explain, why I need a cast at the point <<< ?

Thanks

Phil

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Thread

Generic cannot be applied Philipp Kraus <philipp.kraus.flashpixx@gmail.com> - 2015-11-25 13:33 -0800
  Re: Generic cannot be applied Arne Vajhøj <arne@vajhoej.dk> - 2015-11-25 16:53 -0500
  Re: Generic cannot be applied Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-11-25 17:00 -0500
  Re: Generic cannot be applied Joshua Cranmer 🐧 <Pidgeot18@verizon.invalid> - 2015-11-26 11:06 -0600

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