public static Map getConfigFromClasspath()

in storm-client/src/jvm/org/apache/storm/utils/Utils.java [1692:1757]
48 lines of code
18 McCabe index (conditional complexity)

    public static Map<String, Object> getConfigFromClasspath(List<String> cp, Map<String, Object> conf) throws IOException {
        if (cp == null || cp.isEmpty()) {
            return conf;
        }
        Yaml yaml = new Yaml(new SafeConstructor(new LoaderOptions()));
        Map<String, Object> defaultsConf = null;
        Map<String, Object> stormConf = null;

        // Based on how Java handles the classpath
        // https://docs.oracle.com/javase/8/docs/technotes/tools/unix/classpath.html
        for (String part : cp) {
            File f = new File(part);

            if (f.getName().equals("*")) {
                // wildcard is given in file
                // in java classpath, '*' is expanded to all jar/JAR files in the directory
                File dir = f.getParentFile();
                if (dir == null) {
                    // it happens when part is just '*' rather than denoting some directory
                    dir = new File(".");
                }

                File[] jarFiles = dir.listFiles((dir1, name) -> name.endsWith(".jar") || name.endsWith(".JAR"));

                // Quoting Javadoc in File.listFiles(FilenameFilter filter):
                // Returns {@code null} if this abstract pathname does not denote a directory, or if an I/O error occurs.
                // Both things are not expected and should not happen.
                if (jarFiles == null) {
                    throw new IOException("Fail to list jar files in directory: " + dir);
                }

                for (File jarFile : jarFiles) {
                    JarConfigReader jarConfigReader = new JarConfigReader(yaml, defaultsConf, stormConf, jarFile).readJar();
                    defaultsConf = jarConfigReader.getDefaultsConf();
                    stormConf = jarConfigReader.getStormConf();
                }
            } else if (f.isDirectory()) {
                // no wildcard, directory
                if (defaultsConf == null) {
                    defaultsConf = readConfIgnoreNotFound(yaml, new File(f, "defaults.yaml"));
                }

                if (stormConf == null) {
                    stormConf = readConfIgnoreNotFound(yaml, new File(f, "storm.yaml"));
                }
            } else if (f.isFile()) {
                // no wildcard, file
                String fileName = f.getName();
                if (fileName.endsWith(".zip") || fileName.endsWith(".ZIP")) {
                    JarConfigReader jarConfigReader = new JarConfigReader(yaml, defaultsConf, stormConf, f).readZip();
                    defaultsConf = jarConfigReader.getDefaultsConf();
                    stormConf = jarConfigReader.getStormConf();
                } else if (fileName.endsWith(".jar") || fileName.endsWith(".JAR")) {
                    JarConfigReader jarConfigReader = new JarConfigReader(yaml, defaultsConf, stormConf, f).readJar();
                    defaultsConf = jarConfigReader.getDefaultsConf();
                    stormConf = jarConfigReader.getStormConf();
                }
                // Class path entries that are neither directories nor archives (.zip or JAR files)
                // nor the asterisk (*) wildcard character are ignored.
            }
        }
        if (stormConf != null) {
            defaultsConf.putAll(stormConf);
        }
        return defaultsConf;
    }