qhgXMLNode and qhgXMLTree¶

The class qhgXMLTree represents the document tree generated from a simplified XML file normally used for population input.

The class qhgNode represents a node in such an document tree, and provides methods for reading and writing.

Code:: qhgXML.h

qhgXML.cpp

Public Methods (`qhgNode`)¶

`createInstance`¶

static qhgNode *createInstance(char *pLine, LineReader *pLR, int iLevel);

Creates a new qhgNode object from a current line.

pLine: Current line to be parsed.
pLR: A LineReader object which delivers the lines of the XML file.
iLevel: The level of the new node

Returns the new qhgNode object resulting from the parsing of the XML file.

`createRoot`¶

static qhgNode *createRoot();

Returns an empty QHGNode.

`destructor`¶

~qhgNode();

The destructor.

`getName`¶

const std::string getName();

Returns this qhgNode’s name.

`destructor`¶

qhgNode  *getNext();

Returns this qhgNode’s next sibling.

`getChild`¶

qhgNode  *getChild();

Returns this qhgNode’s first child.

`getAttrs`¶

stringmap &getAttrs();

Returns this qhgNode’s attributes as a map {attribute_name => attribute_value}.

`getTagType`¶

int getTagType();

Returns this qhgNode’s tag type.

Possible types:

Name	Value	Meaning
TYPE_NO_TAG	0	No tag
TYPE_START_TAG	1	A start tag, e.g. `<param name="x1">`
TYPE_EMPTY_TAG	2	An empty tag, e.g. `<param name="x1" />`
TYPE_END_TAG	3	An end tag, e.g. `</param>`

`setName`¶

void setName(const std::string sName);

Set the name of the this qhgNode.

`destructor`¶

void setNext(qhgNode *pNext);

Set the next qhgNode` for this ``qhgNode.

`destructor`¶

void setChild(qhgNode *pChild);

Set the first child for this qhgNode.

`getCurWord`¶

const char *getCurWord();

Returns the scanner’s current word. A word satrts with a letter or an underscore followed by letter, numbers, underscores and some other special characters.

In this context a word is usually the name of a tag, or an attribute.

`destructor`¶

const char *getCurString()  { return m_sCurString;};

Returns the scanner’s current string. A string is a character sequence enclosed by double quotes.

In this context a string is usually the value of an attribute.

Protected Methodes (`qhgNode`)¶

`constructor`¶

qhgNode(LineReader *pLR, int iLevel);

The constructor stores the LineReader and the level for later use.

pLR: A LineReader object which delivers the lines of the XML file.
iLevel: The level of the new node.

`init`¶

int init(char *pLine);

Parses the specified line. This creates a qhgNode for the tag and all enclosed tags.

pLine: A string containing a tag to be parsed.

Returns 0 on success, -1 on failure.

`parseNode`¶

int parseNode(char *pLine);

Parses the node defined in the specified string. This will create a node from the data collected by parseTag().

pLine: A string containing a tag to be parsed.

Returns 0 on success, -1 on failure.

`parseTag`¶

int parseTag(char *pLine);

Parse the tag from the specified string. This will extract the name, the tag type and the attributes.

pLine: A string containing a tag to be parsed.

Returns 0 on success, -1 on failure.

`skipBlanks`¶

char *skipBlanks();

Skips blanks in the input (scanner).

Retruns the current character in the input.

`getNextSym`¶

int   getNextSym();

Finds and returns the next symbol in the input (Scanner):

Name	Value	Meaning
SYM_NONE	0	No (known) symbol
SYM_WORD	1	A word*
SYM_OPEN_BRA	2	The character ‘<’
SYM_CLOSE_BRA	3	The character ‘>’
SYM_OPEN_SLASH_BRA	4	The string “</”
SYM_CLOSE_SLASH_BRA	5	The string “/>”
SYM_QUOTE	6	The character ‘”’
SYM_EQUALS	7	The character ‘=’
SYM_SLASH	8	The character ‘/’

*A word is a character sequence consisting of letters, numbers, underscores, as well as ‘-’, ‘+’, and ‘$’.

`readWord`¶

char *readWord();

Read the next characters as a word.

Returns the word.

`readString`¶

char *readString();

Read the next characters as a string (i.e. all characters until a double quote is reached).

Returns the string.

Public Methods (`qhgXMLTree`)¶

`createInstance`¶

static qhgXMLTree *createInstance(const std::string sFile);

Creates a qhgXMLTree object for the specified file.

sFile: Name of the file to be read.

`destructor`¶

~qhgXMLTree();

The destructor.

`getRoot`¶

qhgNode *getRoot();

Returns the root of the document tree.

`init`¶

int init(const std::string sFile);

Creates a LineReader object from the file creates a root node and processes al top level tags.

sFile: Name of the file to be read.

Returns 0 on success, -1 on failure.

Example¶

This example reads from an XML file and prints out all elements of the document tree.

Compile with

g++ qhgxml_example.cpp qhgXML.cpp -o qhgxml_example -I ../io -I ../utils -L../utils -lUtils -lz -std=c++20

Code for qhgxml_example:

#include <cstdio>
#include <string>
#include "qhgXML.h"

void showNode(qhgXMLNode *pN, std::string sIndent) {
    printf("%sName %s\n", sIndent.c_str(), pN->getName().c_str());
    stringmap &mA = pN->getAttrs();
    printf("%s  Attrs (%zd):\n", sIndent.c_str(), mA.size());
    stringmap::const_iterator it;

    for (it = mA.begin(); it != mA.end(); ++it) {
        printf("%s    %s : %s\n", sIndent.c_str(), it->first.c_str(), it->second.c_str());
    }

    // count children
    int iNC = 0;
    qhgXMLNode *pC1 = pN->getChild();
    while (pC1 != NULL) {
        iNC++;
        pC1 = pC1->getNext();
    }

    printf("%s  Children (%d)%s\n", sIndent.c_str(), iNC, (iNC>0)?":":"");
    if (iNC > 0) {
        //char sIndent[256];
        //        sprintf(sIndent, "%s    ", pIndent);
        sIndent = sIndent + "    ";
        qhgXMLNode *pC = pN->getChild();
        while (pC != NULL) {
            showNode(pC, sIndent);
            pC = pC->getNext();
        }
    }
}

int main(int iArgC, char *apArgV[]) {

    stringmap mAttr;
    mAttr["name"]="value";

    int iResult = -1;
    if (iArgC > 1) {
        qhgXMLTree *pQX = qhgXMLTree::createInstance(apArgV[1]);
        if (pQX != NULL) {
            printf("qhgXMLTree finished\n");
            showNode(pQX->getRoot(), "");
            delete pQX;
        } else {
            printf("Couldn't create qhgXML\n");

        }
    } else {
        printf("usage %s <xmlfile>\n", apArgV[0]);
    }
    return iResult;
}

Example for a qhg XML file:

<class name="OoANavSHybYchMTDPop" species_name="sapiens" species_id="117">
  <module name="NPersZHybBirthDeathRel">
    <param  name="HybBirthDeathRel_hybminprob" value="0.2021484375" />
  </module>
  <module name="LocEnv">
    <param  name="NPPCap_K_max_sapiens" value="44.74609375" />
    <param  name="NPPCap_K_min_sapiens" value="0.0" />
  </module>
  <module name="PrivParamMix">
    <param  name="NPersHybBirthDeathRel_b0_sapiens" value="0.3099609375" />
    <param  name="NPersHybBirthDeathRel_d0_sapiens" value="0" />
    <param  name="NPersHybBirthDeathRel_theta_sapiens" value="0.3099609375" />
  </module>
  <priorities>
    <prio  name="PersFertility" value="2" />
    <prio  name="GetOld" value="9" />
  </priorities>
</class>

The call

./qhgxml_example test_file.xml

will give the output

qhgXMLTree finished
Name root
  Attrs (0):
  Children (1):
    Name class
      Attrs (3):
        name : OoANavSHybYchMTDPop
        species_id : 117
        species_name : sapiens
      Children (4):
        Name module
          Attrs (1):
            name : NPersZHybBirthDeathRel
          Children (1):
            Name param
              Attrs (2):
                name : HybBirthDeathRel_hybminprob
                value : 0.2021484375
              Children (0)
        Name module
          Attrs (1):
            name : LocEnv
          Children (2):
            Name param
              Attrs (2):
                name : NPPCap_K_max_sapiens
                value : 44.74609375
              Children (0)
            Name param
              Attrs (2):
                name : NPPCap_K_min_sapiens
                value : 0.0
              Children (0)
        Name module
          Attrs (1):
            name : PrivParamMix
          Children (3):
            Name param
              Attrs (2):
                name : NPersHybBirthDeathRel_b0_sapiens
                value : 0.3099609375
              Children (0)
            Name param
              Attrs (2):
                name : NPersHybBirthDeathRel_d0_sapiens
                value : 0
              Children (0)
            Name param
              Attrs (2):
                name : NPersHybBirthDeathRel_theta_sapiens
                value : 0.3099609375
              Children (0)
        Name priorities
          Attrs (0):
          Children (2):
            Name prio
              Attrs (2):
                name : PersFertility
                value : 2
              Children (0)
            Name prio
              Attrs (2):
                name : GetOld
                value : 9
              Children (0)

qhgXMLNode and qhgXMLTree¶

Public Methods (`qhgNode`)¶

`createInstance`¶

`createRoot`¶

`destructor`¶

`getName`¶

`destructor`¶

`getChild`¶

`getAttrs`¶

`getTagType`¶

`setName`¶

`destructor`¶

`destructor`¶

`getCurWord`¶

`destructor`¶

Protected Methodes (`qhgNode`)¶

`constructor`¶

`init`¶

`parseNode`¶

`parseTag`¶

`skipBlanks`¶

`getNextSym`¶

`readWord`¶

`readString`¶

Public Methods (`qhgXMLTree`)¶

`createInstance`¶

`destructor`¶

`getRoot`¶

`init`¶

Example¶

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qhgXMLNode and qhgXMLTree¶

Public Methods (qhgNode)¶

createInstance¶

createRoot¶

destructor¶

getName¶

destructor¶

getChild¶

getAttrs¶

getTagType¶

setName¶

destructor¶

destructor¶

getCurWord¶

destructor¶

Protected Methodes (qhgNode)¶

constructor¶

init¶

parseNode¶

parseTag¶

skipBlanks¶

getNextSym¶

readWord¶

readString¶

Public Methods (qhgXMLTree)¶

createInstance¶

destructor¶

getRoot¶

init¶

Example¶

Public Methods (`qhgNode`)¶

`createInstance`¶

`createRoot`¶

`destructor`¶

`getName`¶

`destructor`¶

`getChild`¶

`getAttrs`¶

`getTagType`¶

`setName`¶

`destructor`¶

`destructor`¶

`getCurWord`¶

`destructor`¶

Protected Methodes (`qhgNode`)¶

`constructor`¶

`init`¶

`parseNode`¶

`parseTag`¶

`skipBlanks`¶

`getNextSym`¶

`readWord`¶

`readString`¶

Public Methods (`qhgXMLTree`)¶

`createInstance`¶

`destructor`¶

`getRoot`¶

`init`¶