Consider the class Class Value { Private T v; Public Value(T v1){ V = v1; } Public void output(){ System.out.println(v); } } The code Value nV1 = new Value(34.5); A) will cause a compiler error B) will compile correctly,but cause an exception at run time C) will compile and run correctly D) None of the above

Question

Consider the class Class Value < T extends Number > { Private T v; Public Value(T v1){ V = v1; } Public void output(){ System.out.println(v); } } The code Value< Number > nV1 = new Value< Double >(34.5); A) will cause a compiler error B) will compile correctly,but cause an exception at run time C) will compile and run correctly D) None of the above

Quizplus · Accepted Answer

The code will cause a compiler error because the generic type parameter <T extends Number> is specified as Number, but an instance of Value is being created with Double, which is not allowed. The type parameter must match exactly.

Consider the Class Class Value < T Extends Number >