public void extract()

in maven-release-manager/src/main/java/org/apache/maven/shared/release/transform/jdom2/JDomModelETL.java [95:150]
39 lines of code
4 McCabe index (conditional complexity)

    public void extract(File pomFile) throws ReleaseExecutionException {
        try {
            String content = ReleaseUtil.readXmlFile(pomFile, ls);
            // we need to eliminate any extra whitespace inside elements, as JDOM2 will nuke it
            content = content.replaceAll("<([^!][^>]*?)\\s{2,}([^>]*?)>", "<$1 $2>");
            content = content.replaceAll("(\\s{2,})/>", "$1 />");

            SAXBuilder builder = new SAXBuilder();
            document = builder.build(new StringReader(content));

            // Normalize line endings to platform's style (XML processors like JDOM2 normalize line endings to "\n" as
            // per section 2.11 of the XML spec)
            normaliseLineEndings(document);

            // rewrite DOM as a string to find differences, since text outside the root element is not tracked
            StringWriter w = new StringWriter();
            Format format = Format.getRawFormat();
            format.setLineSeparator(ls);
            XMLOutputter out = new XMLOutputter(format);
            out.output(document.getRootElement(), w);

            int index = content.indexOf(w.toString());
            if (index >= 0) {
                intro = content.substring(0, index);
                outtro = content.substring(index + w.toString().length());
            } else {
                /*
                 * NOTE: Due to whitespace, attribute reordering or entity expansion the above indexOf test can easily
                 * fail. So let's try harder. Maybe some day, when JDOM2 offers a StaxBuilder and this builder employes
                 * XMLInputFactory2.P_REPORT_PROLOG_WHITESPACE, this whole mess can be avoided.
                 */
                // CHECKSTYLE_OFF: LocalFinalVariableName
                final String SPACE = "\\s++";
                final String XML = "<\\?(?:(?:[^\"'>]++)|(?:\"[^\"]*+\")|(?:'[^\']*+'))*+>";
                final String INTSUB = "\\[(?:(?:[^\"'\\]]++)|(?:\"[^\"]*+\")|(?:'[^\']*+'))*+\\]";
                final String DOCTYPE =
                        "<!DOCTYPE(?:(?:[^\"'\\[>]++)|(?:\"[^\"]*+\")|(?:'[^\']*+')|(?:" + INTSUB + "))*+>";
                final String PI = XML;
                final String COMMENT = "<!--(?:[^-]|(?:-[^-]))*+-->";

                final String INTRO =
                        "(?:(?:" + SPACE + ")|(?:" + XML + ")|(?:" + DOCTYPE + ")|(?:" + COMMENT + ")|(?:" + PI + "))*";
                final String OUTRO = "(?:(?:" + SPACE + ")|(?:" + COMMENT + ")|(?:" + PI + "))*";
                final String POM = "(?s)(" + INTRO + ")(.*?)(" + OUTRO + ")";
                // CHECKSTYLE_ON: LocalFinalVariableName

                Matcher matcher = Pattern.compile(POM).matcher(content);
                if (matcher.matches()) {
                    intro = matcher.group(1);
                    outtro = matcher.group(matcher.groupCount());
                }
            }
        } catch (JDOMException | IOException e) {
            throw new ReleaseExecutionException("Error reading POM: " + e.getMessage(), e);
        }
    }