KeyValuePrinter Class Reference

create human-readable or JSON output for key value pairs. More...

#include <KeyValuePrinter.h>

Collaboration diagram for KeyValuePrinter:

Public Member Functions
	KeyValuePrinter (bool use_json, unsigned key_max_length=10)
	Ctor. More...
std::string	string () const
	Return completed string.
template<class T >
void	put (const std::string &key, const T &value)
	Add one key-value pair.
template<class T >
void	put (const std::string &key, const std::map< std::string, T > &value)
	Specialization for map<>

Private Member Functions
std::string	escape (const std::string &value) const
	escape string.
std::string	escape (const char *value) const
	escape string literals.
template<class T >
std::string	escape (const T &value) const
	escape numeric value.
template<class T >
std::string	escape (const std::vector< T > &value) const
	escape vector<T>.
template<class T >
std::string	escape (const std::map< std::string, T > &value) const
	escape map<string, T>.

Private Attributes
bool	m_json
	create JSON output?
unsigned	m_maxpad
	for human-readable output: how much padding after key?
std::string	m_delim
	for JSON: comma to print after prev entry.
std::stringstream	m_stream
	output being built.

Detailed Description

create human-readable or JSON output for key value pairs.

Usage example for human-readable output:

KeyValuePrinter pr(false); //JSON=false
pr.put("a", 123);
pr.put("bbbbb", "string");
pr.put("ccccccc", std::vector<std::string>({"string", "abc"}));
std::cout << pr.string();
//which prints
// a:          123
// bbbbb:      string
// ccccccc:    [string, abc]

std::string, numeric types, std::vector<SUPPORTED TYPE>, and std::map<std::string, SUPPORTED TYPE> * are supported as value types for put().

JSON output is suitable for reading via e.g. json.loads() in Python, and performs the necessary escaping for strings. Compared to boost::property_tree::json_parser::write_json, KeyValuePrinter handles non-string types correctly.

Definition at line 46 of file KeyValuePrinter.h.

Constructor & Destructor Documentation

KeyValuePrinter()

KeyValuePrinter ( bool  use_json, unsigned  key_max_length = 10  )

inlineexplicit

Ctor.

Parameters

use_json	true for JSON output, false for human-readable output.
key_max_length	for human-readable output, this should be equal to strlen(longest_key) for aligning values in output.

Definition at line 53 of file KeyValuePrinter.h.

                                                                         :
      m_json(use_json),
      m_maxpad(key_max_length + 2),
      m_delim("")
    { }

---

The documentation for this class was generated from the following files:

• framework/utilities/include/KeyValuePrinter.h
• framework/utilities/src/KeyValuePrinter.cc