1 /**********************************************************
3 * ---------------------
4 * Implementation of the class that receives events from the XML parser and
5 * invokes corresponding construction methods of the storage interface.
7 * Author: Greg Leighton
10 * 05/11/08 -- Fixed bug related to parsing empty elements
11 * -- Set parser properties to automatically resolve
12 * entity references and load external DTD if present
13 * -- Modified processEndDocument() by adding a nodeFinished()
14 * call to the storage interface to close off the
20 #include "XMLDocShredder.h"
21 #include "SXSIStorageInterface.h"
22 #include <libxml++/exceptions/parse_error.h>
27 void XMLDocShredder::setProperties(){
28 /* instruct the parser to expand entity references and report as
31 reader_->set_parser_property(
32 TextReader::SubstEntities, true);
34 /* instruct parser to read external DTD, if present. This is
35 * needed to obtain any entity definitions in the DTD
37 reader_->set_parser_property(
38 TextReader::LoadDtd, true);
43 reader_->set_parser_property(
44 TextReader::DefaultAttrs, true);
47 /* but we don't want to do validation since it would slow us down
51 reader_->set_parser_property(
52 TextReader::Validate, false);
55 XMLDocShredder::XMLDocShredder(const unsigned char * data,
56 TextReader::size_type size,
62 reader_ = new TextReader(data,size,"");
64 storageIfc_ = new SXSIStorageInterface(sf,iet,dtc);
68 XMLDocShredder::XMLDocShredder(const string inFileName,int sf, bool iet, bool dtc)
71 reader_ = new TextReader(inFileName);
73 storageIfc_ = new SXSIStorageInterface(sf,iet,dtc);
77 XMLDocShredder::~XMLDocShredder()
85 void XMLDocShredder::processStartElement()
87 // fetch element name; this will be the full qualified name
88 ustring name = reader_->get_name();
91 storageIfc_->newText(buffer); //prevText
94 storageIfc_->newChild(name);
96 /* We must be really carefull here. calling process attributes moves
97 the document pointer on the last attribute, hence calling reader_->is_empty
98 afterwards will yield the wrong result. It is better to call it while we are
99 on the element and generate a nodeFinished() call at the end */
100 empty = reader_->is_empty_element();
103 // now, process attributes
104 if (reader_->has_attributes())
111 storageIfc_->newText(""); //myText
112 storageIfc_->nodeFinished(name);
118 void XMLDocShredder::processEndElement()
120 // tell the storage interface that the current node has been completely processed
121 storageIfc_->newText(buffer); //prevText
123 storageIfc_->nodeFinished(reader_->get_name());
126 void XMLDocShredder::processPCDATA()
128 // send the content of this PCDATA node to the storage interface as a text node
130 if (reader_->has_value())
132 buffer += reader_->get_value();
137 void XMLDocShredder::processAttributes()
139 reader_->move_to_first_attribute();
141 string nspaceStr = "xmlns";
142 storageIfc_->newText(""); //prevText
143 storageIfc_->newChild("<@>");
146 ustring name = reader_->get_name();
147 ustring value = reader_->get_value();
149 /* the libxml++ TextReader treats the xmlns attribute like an ordinary attribute,
150 * so we have to extract it and build a namespace uri node out of it before
151 * passing to the storage interface */
153 if ((name.find(nspaceStr.c_str(), 0, 5)) == 0)
155 storageIfc_->newChild(":" + value);
156 storageIfc_->nodeFinished(":" + value);
159 /* otherwise, this is an ordinary attribute, so we construct a new child node of the
160 * parent element to store the attribute name, possessing a child text node storing the
161 * attribute value. Then, we close off the attribute node with a call to nodeFinished()
166 storageIfc_->newText(""); //prevText
167 storageIfc_->newChild(name);
168 storageIfc_->newText(value);
169 storageIfc_->nodeFinished(name);
172 while (reader_->move_to_next_attribute());
173 storageIfc_->newText(""); //nextText
174 storageIfc_->nodeFinished("<@>");
177 void XMLDocShredder::processSignificantWhitespace()
179 // each significant whitespace sequence constructs a text node
180 buffer += reader_->get_value();
184 void XMLDocShredder::processStartDocument(const string docName)
186 // tell storage interface to construct the document name
187 storageIfc_->newChild("");
191 void XMLDocShredder::processEndDocument()
193 /* tell the storage interface that document parsing has finished, and structures
194 * can now be written to disk. */
195 storageIfc_->newText("");
196 storageIfc_->nodeFinished("");
197 storageIfc_->parsingFinished();
200 void XMLDocShredder::processComment()
202 //storageIfc_->newChild("!" + reader_->get_value());
203 //storageIfc_->nodeFinished();
206 void XMLDocShredder::processProcessingInstruction()
208 ustring name = reader_->get_name();
209 ustring value = reader_->get_value();
211 /* Create a child node to store the target of the PI, append a text node to it to store
212 * the PI data, send to the storage interface. Close off the PI node with a call to
216 // storageIfc_->newChild("?" + name);
217 // storageIfc_->newText(value);
218 // storageIfc_->nodeFinished();
221 void XMLDocShredder::processDocTypeDeclaration()
223 /* We currently ignore the DOCTYPE declaration, but we'll provide this method skeleton
224 * in case we do want to process it in the future.
228 void XMLDocShredder::processCDATASection()
230 /* Currently, we don't preserve CDATA sections since they aren't part of the XPath data
231 * model. Instead, we simply pass the converted text value to the storage interface as
232 * a text node attached to the current context node.
235 ustring value = reader_->get_value();
236 storageIfc_->newText(value);
241 void XMLDocShredder::processUnknownNodeType()
243 cout << "unknown token encountered during parsing" << endl;
244 throw xmlpp::parse_error("unknown token encountered during parsing");
248 void XMLDocShredder::parse()
250 while (reader_->read() && (reader_->get_read_state() != TextReader::Error))
252 switch (reader_->get_node_type())
254 case TextReader::Element:
255 processStartElement();
258 case TextReader::Text:
262 case TextReader::EndElement:
266 case TextReader::SignificantWhitespace:
267 processSignificantWhitespace();
270 case TextReader::Comment:
274 case TextReader::DocumentType:
275 processDocTypeDeclaration();
278 case TextReader::ProcessingInstruction:
279 processProcessingInstruction();
282 case TextReader::CDATA:
283 processCDATASection();
286 case TextReader::None:
287 processUnknownNodeType();
291 int type = reader_->get_node_type();
292 cout << " Node type: " << type << endl;