Library: Data
Package: DataCore
Header: Poco/Data/RowFormatter.h
Row formatter is an abstract class providing definition for row formatting functionality. For custom formatting strategies, inherit from this class and override formatNames() and formatValues() member functions.
Row formatter can be either passed to the RecordSet at construction time, like in the following example:
RecordSet rs(session. "SELECT * FROM Table", new MyRowFormater);
or it can be supplied to the statement as in the following example:
MyRowFormatter rf session << "SELECT * FROM Table", format(rf);
If no formatter is externally supplied to the statement, the SimpleRowFormatter is used. Statement always has the ownership of the row formatter and shares it with rows through RecordSet.
To accomodate for various formatting needs, a formatter can operate in two modes:
When formatter is used in conjunction with Row/RecordSet, the formatting members corresponding to the formater mode are expected to be implemented. If a call is propagated to this parent class, the functions do nothing or silently return empty string respectively.
Known Derived Classes: SimpleRowFormatter
Member Functions: formatNames, formatValues, getMode, getTotalRowCount, postfix, prefix, reset, rowCount, setMode, setPostfix, setPrefix, setTotalRowCount, toString
typedef std::vector < std::string > NameVec;
typedef SharedPtr < std::vector < std::string > > NameVecPtr;
typedef SharedPtr < RowFormatter > Ptr;
typedef std::vector < Poco::Dynamic::Var > ValueVec;
RowFormatter(
const std::string & prefix = "",
const std::string & postfix = "",
Mode mode = FORMAT_PROGRESSIVE
);
Creates the RowFormatter and sets the prefix and postfix to specified values.
virtual ~RowFormatter();
Destroys the RowFormatter.
virtual std::string & formatNames(
const NameVecPtr pNames,
std::string & formattedNames
);
Should be implemented to format the row fields names and return the formatted string. The default implementation clears the names string and returns it.
virtual void formatNames(
const NameVecPtr pNames
);
Should be implemented to format the row fields names. The default implementation does nothing.
virtual std::string & formatValues(
const ValueVec & vals,
std::string & formattedValues
);
Should be implemented to format the row fields values and return the formatted string. The default implementation clears the values string and returns it.
virtual void formatValues(
const ValueVec & vals
);
Should be implemented to format the row fields values. The default implementation does nothing.
Mode getMode() const;
Returns the formater mode.
int getTotalRowCount() const;
Returns zero. Must be implemented by inheriting classes. Typically, total row count shall be set up front through setTotalRowCount() call.
virtual const std::string & postfix() const;
Returns postfix string;
virtual const std::string & prefix() const;
Returns prefix string;
void reset();
Resets the formatter by setting prefix and postfix to empty strings and row count to INVALID_ROW_COUNT.
virtual int rowCount() const;
Returns INVALID_ROW_COUNT. Must be implemented by inheriting classes which maintain count of processed rows.
void setMode(
Mode mode
);
Sets the fromatter mode.
void setTotalRowCount(
int count
);
Sets total row count.
virtual const std::string & toString();
Throws NotImplementedException. Formatters operating in bulk mode should implement this member function to return valid pointer to the formatted result.
void setPostfix(
const std::string & postfix
);
Sets the postfix for the formatter
void setPrefix(
const std::string & prefix
);
Sets the prefix for the formatter.
static const int INVALID_ROW_COUNT = - 1;