private URL findResource()

in core/src/main/java/org/apache/struts2/util/finder/ResourceFinder.java [1301:1398]
81 lines of code
22 McCabe index (conditional complexity)

    private URL findResource(String resourceName, URL... search) {
        for (int i = 0; i < search.length; i++) {
            URL currentUrl = search[i];
            if (currentUrl == null) {
                continue;
            }
            JarFile jarFile;
            try {
                String protocol = currentUrl.getProtocol();
                if ("jar".equals(protocol)) {
                    /*
                    * If the connection for currentUrl or resURL is
                    * used, getJarFile() will throw an exception if the
                    * entry doesn't exist.
                    */
                    URL jarURL = ((JarURLConnection) currentUrl.openConnection()).getJarFileURL();
                    try {
                        JarURLConnection juc = (JarURLConnection) new URL("jar", "", jarURL.toExternalForm() + "!/").openConnection();
                        jarFile = juc.getJarFile();
                    } catch (IOException e) {
                        // Don't look for this jar file again
                        search[i] = null;
                        throw e;
                    }

                    String entryName;
                    if (currentUrl.getFile().endsWith("!/")) {
                        entryName = resourceName;
                    } else {
                        String file = currentUrl.getFile();
                        int sepIdx = file.lastIndexOf("!/");
                        if (sepIdx == -1) {
                            // Invalid URL, don't look here again
                            search[i] = null;
                            continue;
                        }
                        sepIdx += 2;
                        entryName = file.substring(sepIdx) + resourceName;
                    }
                    if ("META-INF/".equals(entryName) && jarFile.getEntry("META-INF/MANIFEST.MF") != null){
                        return targetURL(currentUrl, "META-INF/MANIFEST.MF");
                    }
                    if (jarFile.getEntry(entryName) != null) {
                        return targetURL(currentUrl, resourceName);
                    }
                } else if ("file".equals(protocol)) {
                    String baseFile = currentUrl.getFile();
                    String host = currentUrl.getHost();
                    int hostLength = 0;
                    if (host != null) {
                        hostLength = host.length();
                    }
                    StringBuilder buf = new StringBuilder(2 + hostLength + baseFile.length() + resourceName.length());

                    if (hostLength > 0) {
                        buf.append("//").append(host);
                    }
                    // baseFile always ends with '/'
                    buf.append(baseFile);
                    String fixedResName = resourceName;
                    // Do not create a UNC path, i.e. \\host
                    while (fixedResName.startsWith("/") || fixedResName.startsWith("\\")) {
                        fixedResName = fixedResName.substring(1);
                    }
                    buf.append(fixedResName);
                    String filename = buf.toString();
                    File file = new File(filename);
                    File file2 = new File(URLDecoder.decode(filename));

                    if (file.exists() || file2.exists()) {
                        return targetURL(currentUrl, fixedResName);
                    }
                } else {
                    URL resourceURL = targetURL(currentUrl, resourceName);
                    URLConnection urlConnection = resourceURL.openConnection();

                    try {
                        urlConnection.getInputStream().close();
                    } catch (SecurityException e) {
                        return null;
                    }
                    // HTTP can return a stream on a non-existent file
                    // So check for the return code;
                    if (!"http".equals(resourceURL.getProtocol())) {
                        return resourceURL;
                    }

                    int code = ((HttpURLConnection) urlConnection).getResponseCode();
                    if (code >= 200 && code < 300) {
                        return resourceURL;
                    }
                }
            } catch (IOException | SecurityException e) {
                // Keep iterating through the URL list
            }
        }
        return null;
    }