BX_BOXING_IMMEDIATELY_UNBOXED_TO_PERFORM_COERCION

Bx: Primitive value is boxed then unboxed to perform primitive coercion.
簡單而言，就是將原始型態的值封裝再直接解封裝，這是沒有必要且使效能降低。

A primitive boxed value constructed and then immediately converted into a different primitive type (e.g., new Double(d).intValue()). Just perform direct primitive coercion (e.g., (int) d).
強制轉型即可，以Double而言，它的intValue也只是做強制轉型。

Before:

      private int convertMiliUnit(double aReading){
        return new Double(aReading*1000).intValue();
      }

After:

      private int convertMiliUnit(double aReading){
        return (int)aReading*1000;
      }