XMLCoreNode Class Reference

Simple DOM-like node structure to hold the result of XML parsing. More...

#include <XMLCoreNode.h>

Collaboration diagram for XMLCoreNode:

Public Types
enum	NodeType {   DOCUMENT_NODE , ELEMENT_NODE , COMMENT_NODE , TEXT_NODE ,   ENTITY_NODE , ENTITY_REFERENCE_NODE }
	Classify node types. More...

Public Member Functions
	XMLCoreNode (NodeType type, const std::string &name="", const std::string &value="")
	Constructor.
void	set_attrib (const std::string &name, const std::string &value)
	Set the value of an attribute for this node.
XMLCoreNode *	add_child (std::unique_ptr< XMLCoreNode > child)
	Add a new child to this node.
XMLCoreNode *	get_parent ()
	Get the parent of this node, or nullptr for a top-level node.
const XMLCoreNode *	get_parent () const
	Get the parent of this node, or nullptr for a top-level node.
NodeType	get_type () const
	Return the type of this node.
const std::string &	get_name () const
	Return the name of this node, or an empty string if no name.
const std::string &	get_value () const
	Return the value of this node, or an empty string if no value.
size_t	n_attribs () const
	Return the number of attributes for this node.
std::string	get_attrib_name (size_t i) const
	Return the name of the i'th attribute.
bool	has_attrib (const std::string &name) const
	Test for presence of an attribute with a given name.
std::optional< int >	try_int_attrib (std::string_view name) const
	Try to retrieve an integer attribute.
std::optional< double >	try_double_attrib (std::string_view name) const
	Try to retrieve an double attribute.
const std::string &	get_attrib (std::string_view name) const
	Retrieve the value of an attribute.
int	get_int_attrib (std::string_view name) const
	Retrieve the value of an attribute as an integer.
double	get_double_attrib (std::string_view name) const
	Retrieve the value of an attribute as a double.
const XMLCoreNode *	get_child (const std::string &path) const
	Return the first child matching a pattern, or nullptr.
std::vector< const XMLCoreNode * >	get_children (const std::string &path="*") const
	Return all children matching a pattern.
void	print (const std::string &header, int depth=0) const
void	print (std::ostream &os, const std::string &header, int depth=0) const

Private Member Functions
void	set_parent (XMLCoreNode *parent)
	Set the parent for this node.
template<class T>
std::optional< T >	try_attrib (std::string_view name) const
	Try to retrieve an attribute of type T.
void	collect_children (const std::string &path, std::vector< const XMLCoreNode * > &children, bool only_one) const
	Collect children of this node matching a path.

Private Attributes
XMLCoreNode *	m_parent = nullptr
	The parent of this node, or null for a top-level node.
NodeType	m_type
	The type of this node.
std::string	m_name
	The name of this node.
std::string	m_value
	The value fo this node.
std::map< std::string, std::string, std::less<> >	m_attribs
	Attributes of this node.
std::vector< std::unique_ptr< XMLCoreNode > >	m_children
	Children of this node.

Detailed Description

Simple DOM-like node structure to hold the result of XML parsing.

Definition at line 45 of file XMLCoreNode.h.

Member Enumeration Documentation

NodeType

enum XMLCoreNode::NodeType

Classify node types.

Enumerator
DOCUMENT_NODE
ELEMENT_NODE
COMMENT_NODE
TEXT_NODE
ENTITY_NODE
ENTITY_REFERENCE_NODE

Definition at line 51 of file XMLCoreNode.h.

    {
      DOCUMENT_NODE,
      ELEMENT_NODE,
      COMMENT_NODE,
      TEXT_NODE,
      ENTITY_NODE,
      ENTITY_REFERENCE_NODE
    } NodeType;

Constructor & Destructor Documentation

XMLCoreNode()

XMLCoreNode::XMLCoreNode	(	NodeType	type,
		const std::string &	name = "",
		const std::string &	value = "" )

Constructor.

Parameters

type	The node type.
name	Node name (for elements). @apram value Node value (for text/comments).

Definition at line 37 of file XMLCoreNode.cxx.

  : m_type (type),
    m_name (name),
    m_value (value)
{
}

Member Function Documentation

add_child()

XMLCoreNode * XMLCoreNode::add_child

(

std::unique_ptr< XMLCoreNode >

child

)

Add a new child to this node.

Parameters

child

The child to add.

Children are ordered according to the order of add_child calls.

Definition at line 64 of file XMLCoreNode.cxx.

{
  child->set_parent (this);
  m_children.push_back (std::move (child));
  return m_children.back().get();
}

collect_children()

void XMLCoreNode::collect_children ( const std::string & path, std::vector< const XMLCoreNode * > & children, bool only_one ) const

private

Collect children of this node matching a path.

Parameters

path	Pattern of the child path for which to search.
children[out]	Vector in which to collect matching children.
only_one	If true, stop after finding the first child.

See get_child above for a description of path.

Definition at line 372 of file XMLCoreNode.cxx.

{
  std::string::size_type pos = path.find ('/');
  std::string name = path.substr (0, pos);
  std::string tail;
  if  (pos != std::string::npos) {
    tail = path.substr (pos+1);
  }
 
  for (const auto& child : m_children) {
    if (name == "*" || child->get_name() == name) {
      if (tail.empty()) {
        children.push_back (child.get());
      }
      else {
        child->collect_children (tail, children, only_one);
      }
    }
    if (only_one && !children.empty()) break;
  }
}

get_attrib()

const std::string & XMLCoreNode::get_attrib

(

std::string_view

name

)

const

Retrieve the value of an attribute.

Parameters

name	Name of the attribute.

Throws an exception if the attribute does not exist.

Definition at line 214 of file XMLCoreNode.cxx.

{
  auto it = m_attribs.find (name);
  if (it == m_attribs.end()) {
    throw ExcXMLCore (std::format("Cannot find attribute {} in {}", name, m_name));
  }
  return it->second;
}

get_attrib_name()

std::string XMLCoreNode::get_attrib_name

(

size_t

i

)

const

Return the name of the i'th attribute.

Parameters

i	The index of the attribute.

Indexes count attributes in order sorted by name. Throws an exception if the index is out of range.

Definition at line 133 of file XMLCoreNode.cxx.

{
  if (i >= m_attribs.size()) {
    throw ExcXMLCore ("Out-of-range attribute index " + std::to_string(i) + " in " + m_name);
  }
 
  auto it = m_attribs.begin();
  std::advance (it, i);
  return it->first;
}

get_child()

const XMLCoreNode * XMLCoreNode::get_child

(

const std::string &

path

)

const

Return the first child matching a pattern, or nullptr.

Parameters

path	Pattern of the child path for which to search.

The @path argument is a set of nested child node names, separated by dots. For example, path node1.node2 means to look for a child of the current node named node1, and then look for a child of that one named node2. A node name may also be * to match any child.

Parameters

path	Pattern of the child path for which to search.

The @path argument is a set of nested child node names, separated by slashes. For example, path node1/node2 means to look for a child of the current node named node1, and then look for a child of that one named node2. A node name may also be * to match any child.

Definition at line 267 of file XMLCoreNode.cxx.

{
  std::vector<const XMLCoreNode*> children;
  collect_children (path, children, true);
  if (!children.empty()) {
    return children[0];
  }
  return nullptr;
}

get_children()

std::vector< const XMLCoreNode * > XMLCoreNode::get_children

(

const std::string &

path = "*"

)

const

Return all children matching a pattern.

Parameters

path	Pattern of the child path for which to search.

The @path argument is a set of nested child node names, separated by dots. For example, path node1.node2 means to look for a child of the current node named node1, and then look for a child of that one named node2. A node name may also be * to match any child.

Parameters

path	Pattern of the child path for which to search.

For example, path node1/node2 means to look for a child of the current node named node1, and then look for a child of that one named node2. node named node1, and then look for a child of that one named node2. A node name may also be * to match any child.

Definition at line 288 of file XMLCoreNode.cxx.

{
  std::vector<const XMLCoreNode*> children;
  collect_children (path, children, false);
  return children;
}

get_double_attrib()

double XMLCoreNode::get_double_attrib

(

std::string_view

name

)

const

Retrieve the value of an attribute as a double.

Parameters

name	Name of the attribute.

Throws an exception if the attribute does not exist or cannot be converted to a double.

Definition at line 248 of file XMLCoreNode.cxx.

{
  std::optional<double> val = try_double_attrib (name);
  if (!val) {
    throw ExcXMLCore (std::format("Bad double attribute {} in {}", name, m_name));
  }
  return val.value();
}

get_int_attrib()

int XMLCoreNode::get_int_attrib

(

std::string_view

name

)

const

Retrieve the value of an attribute as an integer.

Parameters

name	Name of the attribute.

Throws an exception if the attribute does not exist or cannot be converted to an int.

Definition at line 231 of file XMLCoreNode.cxx.

{
  std::optional<int> val = try_int_attrib (name);
  if (!val) {
    throw ExcXMLCore (std::format("Bad integer attribute {} in {}", name, m_name));
  }
  return val.value();
}

get_name()

const std::string & XMLCoreNode::get_name

(

)

const

Return the name of this node, or an empty string if no name.

Definition at line 102 of file XMLCoreNode.cxx.

{
  return m_name;
}

get_parent() [1/2]

XMLCoreNode * XMLCoreNode::get_parent

(

)

Get the parent of this node, or nullptr for a top-level node.

Definition at line 75 of file XMLCoreNode.cxx.

{
  return m_parent;
}

get_parent() [2/2]

const XMLCoreNode * XMLCoreNode::get_parent

(

)

const

Get the parent of this node, or nullptr for a top-level node.

Definition at line 84 of file XMLCoreNode.cxx.

{
  return m_parent;
}

get_type()

XMLCoreNode::NodeType XMLCoreNode::get_type

(

)

const

Return the type of this node.

Definition at line 93 of file XMLCoreNode.cxx.

{
  return m_type;
}

get_value()

const std::string & XMLCoreNode::get_value

(

)

const

Return the value of this node, or an empty string if no value.

Definition at line 111 of file XMLCoreNode.cxx.

{
  return m_value;
}

has_attrib()

bool XMLCoreNode::has_attrib

(

const std::string &

name

)

const

Test for presence of an attribute with a given name.

Parameters

name	Attribute name to test.

Definition at line 149 of file XMLCoreNode.cxx.

{
  return m_attribs.contains (name);
}

n_attribs()

size_t XMLCoreNode::n_attribs

(

)

const

Return the number of attributes for this node.

Definition at line 120 of file XMLCoreNode.cxx.

{
  return m_attribs.size();
}

print() [1/2]

void XMLCoreNode::print	(	const std::string &	header,
		int	depth = 0 ) const

Definition at line 301 of file XMLCoreNode.cxx.

{
  print (std::cout, header, depth);
}

print() [2/2]

void XMLCoreNode::print	(	std::ostream &	os,
		const std::string &	header,
		int	depth = 0 ) const

Definition at line 314 of file XMLCoreNode.cxx.

{
  if (!header.empty()) {
    os << header << std::endl;
  }
 
  if (m_type == TEXT_NODE) {
    bool allspace = m_value.find_last_of(SPACE) == std::string::npos;
    if (!allspace)
      os << m_value << std::endl;
    return;
  }
 
  for (int i = 0; i < depth; i++) os << "  ";
 
  if (m_type == COMMENT_NODE) {
    os << "<!--" << m_value << "-->" << std::endl;
    return;
  }
 
  os << "<" << m_name;
 
  for (const auto& p : m_attribs) {
    os << " " << p.first << "='" << p.second << "'";
  }
 
  os << ">" << std::endl;
 
  for (const auto& child : m_children) {
    child->print (os, "", depth+1);
  }
 
  for (int i = 0; i < depth; i++) os << "  ";
  os << "</" << m_name << ">" << std::endl;
  return;
}

set_attrib()

void XMLCoreNode::set_attrib	(	const std::string &	name,
		const std::string &	value )

Set the value of an attribute for this node.

Parameters

name	Attribute name.
value	Attribute value (as a string).

Definition at line 52 of file XMLCoreNode.cxx.

{
  m_attribs[name] = value;
}

set_parent()

void XMLCoreNode::set_parent ( XMLCoreNode * parent )

private

Set the parent for this node.

Parameters

Pointer

to the parent node.

Definition at line 358 of file XMLCoreNode.cxx.

{
  m_parent = parent;
}

try_attrib()

template<class T>

std::optional< T > XMLCoreNode::try_attrib ( std::string_view name ) const

private

Try to retrieve an attribute of type T.

param name Name of the attribute to retrieve.

Returns an invalid optional if the attribute does not exist or cannot be converted to T.

Definition at line 163 of file XMLCoreNode.cxx.

{
  std::optional<T> ret;
  auto it = m_attribs.find (name);
  if (it == m_attribs.end()) return ret;
 
  T val = 0;
  std::string::size_type beg = it->second.find_first_not_of (SPACE);
  std::string::size_type end = it->second.find_last_not_of (SPACE);
  if (beg == std::string::npos || end == std::string::npos) return ret;
  const char* begp = it->second.c_str()+beg;
  const char* endp = it->second.c_str()+end+1;
  auto [ptr, ec] = std::from_chars (begp, endp, val);
  if (ec == std::errc() && ptr == endp)
    ret.emplace (val);
  return ret;
}

try_double_attrib()

std::optional< double > XMLCoreNode::try_double_attrib

(

std::string_view

name

)

const

Try to retrieve an double attribute.

Parameters

name	Name of the attribute.

Returns an invalid optional if the attribute does not exist or cannot be converted to a double.

Definition at line 202 of file XMLCoreNode.cxx.

{
  return try_attrib<double> (name);
}

try_int_attrib()

std::optional< int > XMLCoreNode::try_int_attrib

(

std::string_view

name

)

const

Try to retrieve an integer attribute.

Parameters

name	Name of the attribute.

Returns an invalid optional if the attribute does not exist or cannot be converted to an integer.

Definition at line 189 of file XMLCoreNode.cxx.

{
  return try_attrib<int> (name);
}

Member Data Documentation

m_attribs

std::map<std::string, std::string, std::less<> > XMLCoreNode::m_attribs

private

Attributes of this node.

Definition at line 278 of file XMLCoreNode.h.

m_children

std::vector<std::unique_ptr<XMLCoreNode> > XMLCoreNode::m_children

private

Children of this node.

Definition at line 281 of file XMLCoreNode.h.

m_name

std::string XMLCoreNode::m_name

private

The name of this node.

Definition at line 272 of file XMLCoreNode.h.

m_parent

XMLCoreNode* XMLCoreNode::m_parent = nullptr

private

The parent of this node, or null for a top-level node.

Definition at line 266 of file XMLCoreNode.h.

m_type

NodeType XMLCoreNode::m_type

private

The type of this node.

Definition at line 269 of file XMLCoreNode.h.

m_value

std::string XMLCoreNode::m_value

private

The value fo this node.

Definition at line 275 of file XMLCoreNode.h.

---

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

• XMLCoreNode.h
• XMLCoreNode.cxx