/**
* Searches for a tag in a page.
*
* @param tag the name of the tag
* @param object an identifier to find the marked content
* @param page a page dictionary
* @throws IOException
*/
public void parseTag(String tag, PdfObject object, PdfDictionary page) throws IOException {
PRStream stream = (PRStream) page.getAsStream(PdfName.CONTENTS);
// if the identifier is a number, we can extract the content right away
if (object instanceof PdfNumber) {
PdfNumber mcid = (PdfNumber) object;
RenderFilter filter = new MarkedContentRenderFilter(mcid.intValue());
TextExtractionStrategy strategy = new SimpleTextExtractionStrategy();
FilteredTextRenderListener listener = new FilteredTextRenderListener(strategy, filter);
PdfContentStreamProcessor processor = new PdfContentStreamProcessor(listener);
processor.processContent(PdfReader.getStreamBytes(stream), page.getAsDict(PdfName.RESOURCES));
out.print(SimpleXMLParser.escapeXML(listener.getResultantText(), true));
}
// if the identifier is an array, we call the parseTag method
// recursively
else if (object instanceof PdfArray) {
PdfArray arr = (PdfArray) object;
int n = arr.size();
for (int i = 0; i < n; i++) {
parseTag(tag, arr.getPdfObject(i), page);
if (i < n - 1) out.println();
}
}
// if the identifier is a dictionary, we get the resources from the
// dictionary
else if (object instanceof PdfDictionary) {
PdfDictionary mcr = (PdfDictionary) object;
parseTag(tag, mcr.getDirectObject(PdfName.MCID), mcr.getAsDict(PdfName.PG));
}
}
/**
* Parses a string with structured content.
*
* @param reader the PdfReader that has access to the PDF file
* @param os the OutputStream to which the resulting xml will be written
* @param charset the charset to encode the data
* @since 5.0.5
*/
public void convertToXml(PdfReader reader, OutputStream os, String charset) throws IOException {
this.reader = reader;
OutputStreamWriter outs = new OutputStreamWriter(os, charset);
out = new PrintWriter(outs);
// get the StructTreeRoot from the root object
PdfDictionary catalog = reader.getCatalog();
PdfDictionary struct = catalog.getAsDict(PdfName.STRUCTTREEROOT);
// Inspect the child or children of the StructTreeRoot
inspectChild(struct.getDirectObject(PdfName.K));
out.flush();
out.close();
}
/**
* If the child of a structured element is a dictionary, we inspect the child; we may also draw a
* tag.
*
* @param k the child dictionary to inspect
*/
public void inspectChildDictionary(PdfDictionary k) throws IOException {
if (k == null) return;
PdfName s = k.getAsName(PdfName.S);
if (s != null) {
String tagN = PdfName.decodeName(s.toString());
String tag = fixTagName(tagN);
out.print("<");
out.print(tag);
out.print(">");
PdfDictionary dict = k.getAsDict(PdfName.PG);
if (dict != null) parseTag(tagN, k.getDirectObject(PdfName.K), dict);
inspectChild(k.get(PdfName.K));
out.print("</");
out.print(tag);
out.println(">");
} else inspectChild(k.get(PdfName.K));
}
