code: public String getTypeGenericErased(int typeParamIndex) {
          String extend = typeGenericExtends[typeParamIndex];
          return extend.startsWith(" extends ") ? extend.substring(9) : "Object";
      }
docs: Gets the extends clause of the parameterisation of the bean, such as '{@code  extends Foo}'.
  @param typeParamIndex  the zero-based index of the type parameter
  @return the generic type extends clause, or a blank string if not generic or no extends, not null