EpubParser.java 文件源码

private String containerXmlParser(String containerData) throws EpubParserException {           //parsing container.xml
    try {
        String xml = containerData.replaceAll("[^\\x20-\\x7e]", "").trim();         //in case encoding problem

        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        DocumentBuilder builder = factory.newDocumentBuilder();
        Document document = builder.parse(new InputSource(new StringReader(xml)));
        document.getDocumentElement().normalize();
        if (document == null) {
            throw new EpubParserException("Error while parsing container.xml");
        }

        Element rootElement = (Element) ((Element) document.getDocumentElement().getElementsByTagName("rootfiles").item(0)).getElementsByTagName("rootfile").item(0);
        if (rootElement != null) {
            String opfFile = rootElement.getAttribute("full-path");
            if (opfFile == null) {
                throw new EpubParserException("Missing root file element in container.xml");
            }

            //Log.d(TAG, "Root file: " + opfFile);
            return opfFile;                    //returns opf file
        }
    } catch (ParserConfigurationException | SAXException | IOException e) {
        e.printStackTrace();
    }
    return null;
}