protected ClassLoader getClassLoader()

in shared-libraries/servicemix-common/src/main/java/org/apache/servicemix/common/xbean/ClassLoaderXmlPreprocessor.java [331:438]
89 lines of code
17 McCabe index (conditional complexity)

    protected ClassLoader getClassLoader(SpringApplicationContext applicationContext, XmlBeanDefinitionReader reader, Document document) {
        // determine the classLoader
        ClassLoader classLoader;
        NodeList classpathElements = document.getDocumentElement().getElementsByTagName("classpath");
        if (classpathElements.getLength() < 1) {
            classLoader = getParentClassLoader(applicationContext);
        } else if (classpathElements.getLength() > 1) {
            throw new FatalBeanException("Expected only classpath element but found " + classpathElements.getLength());
        } else {
            Element classpathElement = (Element) classpathElements.item(0);
            
            // Delegation mode
            boolean inverse = false;
            String inverseAttr = classpathElement.getAttribute("inverse");
            if (inverseAttr != null && "true".equalsIgnoreCase(inverseAttr)) {
                inverse = true;
            }

            // build hidden classes
            List<String> hidden = new ArrayList<String>();
            NodeList hiddenElems = classpathElement.getElementsByTagName("hidden");
            for (int i = 0; i < hiddenElems.getLength(); i++) {
                Element hiddenElement = (Element) hiddenElems.item(i);
                String pattern = ((Text) hiddenElement.getFirstChild()).getData().trim();
                hidden.add(pattern);
            }

            // build non overridable classes
            List<String> nonOverridable = new ArrayList<String>();
            NodeList nonOverridableElems = classpathElement.getElementsByTagName("nonOverridable");
            for (int i = 0; i < nonOverridableElems.getLength(); i++) {
                Element nonOverridableElement = (Element) nonOverridableElems.item(i);
                String pattern = ((Text) nonOverridableElement.getFirstChild()).getData().trim();
                nonOverridable.add(pattern);
            }

            // build the classpath
            List<String> classpath = new ArrayList<String>();
            NodeList locations = classpathElement.getElementsByTagName("location");
            for (int i = 0; i < locations.getLength(); i++) {
                Element locationElement = (Element) locations.item(i);
                String location = ((Text) locationElement.getFirstChild()).getData().trim();
                classpath.add(location);
            }
            
            // Add shared libraries
            List<String> sls = new ArrayList<String>();
            NodeList libraries = classpathElement.getElementsByTagName("library");
            for (int i = 0; i < libraries.getLength(); i++) {
                Element locationElement = (Element) libraries.item(i);
                String library = ((Text) locationElement.getFirstChild()).getData().trim();
                sls.add(library);
            }

            // Add components
            List<String> components = new ArrayList<String>();
            NodeList componentList = classpathElement.getElementsByTagName("component");
            for (int i = 0; i < componentList.getLength(); i++) {
                Element locationElement = (Element) componentList.item(i);
                String component = ((Text) locationElement.getFirstChild()).getData().trim();
                components.add(component);
            }

            // convert the paths to URLS
            URL[] urls;
            if (classpath.size() != 0) {
                List<URL> urlsList = new LinkedList<URL>();
                for (ListIterator<String> iterator = classpath.listIterator(); iterator.hasNext();) {
                    String location = iterator.next();
                    List<URL> locationUrls = getResources(location);
                    for (URL url : locationUrls) {
                        urlsList.add(url);
                    }
                }
                urls = urlsList.toArray(new URL[urlsList.size()]);
            } else {
                urls = getDefaultLocations();
            }

            // create the classloader
            List<ClassLoader> parents = new ArrayList<ClassLoader>();
            parents.add(getParentClassLoader(applicationContext));
            for (String library : sls) {
                ClassLoader cl = this.component.getContainer().getSharedLibraryClassLoader(library);
                if (cl == null) {
                    throw new IllegalStateException("No such shared library: " + library);
                }
                parents.add(cl);
            }
            for (String component : components) {
                ClassLoader cl = this.component.getContainer().getComponentClassLoader(component);
                if (cl == null) {
                    throw new IllegalStateException("No such component: " + component);
                }
                parents.add(cl);
            }
            classLoader = new JarFileClassLoader(applicationContext.getDisplayName(),
                                                 urls, 
                                                 parents.toArray(new ClassLoader[parents.size()]),
                                                 inverse,
                                                 hidden.toArray(new String[hidden.size()]),
                                                 nonOverridable.toArray(new String[nonOverridable.size()]));

            // remove the classpath element so Spring doesn't get confused
            document.getDocumentElement().removeChild(classpathElement);
        }
        return classLoader;
    }