@Nullable
    public Double getDouble(int pos) {
        final Number n = getNumber(pos);
        return n == null ? null : n.doubleValue();
    }
Retrieves an out parameter as a Double object.

@param pos The out parameter index
@return The value as an Double object. Can be null.
core/src/main/java/org/jdbi/v3/core/statement/OutParameters.java