static Transform transformFromArgs()

in freemarker-core/src/main/java/freemarker/ext/dom/Transform.java [113:185]
73 lines of code
25 McCabe index (conditional complexity)

    static Transform transformFromArgs(String[] args) throws IOException {
        int i = 0;
        String input = null, output = null, ftl = null, loc = null, enc = null;
        while (i < args.length) {
            String dashArg = args[i++];
            if (i >= args.length) {
                throw new IllegalArgumentException("");
            }
            String arg = args[i++];
            if (dashArg.equals("-in")) {
                if (input != null) {
                    throw new IllegalArgumentException("The input file should only be specified once");
                }
                input = arg;
            } else if (dashArg.equals("-ftl")) {
                if (ftl != null) {
                    throw new IllegalArgumentException("The ftl file should only be specified once");
                }
                ftl = arg;
            } else if (dashArg.equals("-out")) {
                if (output != null) {
                    throw new IllegalArgumentException("The output file should only be specified once");
                }
                output = arg;
            } else if (dashArg.equals("-locale")) {
                if (loc != null) {
                    throw new IllegalArgumentException("The locale should only be specified once");
                }
                loc = arg;
            } else if (dashArg.equals("-encoding")) {
                if (enc != null) {
                    throw new IllegalArgumentException("The encoding should only be specified once");
                }
                enc = arg;
            } else {
                throw new IllegalArgumentException("Unknown input argument: " + dashArg);
            }
        }
        if (input == null) {
            throw new IllegalArgumentException("No input file specified.");
        }
        if (ftl == null) {
            throw new IllegalArgumentException("No ftl file specified.");
        }
        File inputFile = new File(input).getAbsoluteFile();
        File ftlFile = new File(ftl).getAbsoluteFile();
        if (!inputFile.exists()) {
            throw new IllegalArgumentException("Input file does not exist: " + input);
        }
        if (!ftlFile.exists()) {
            throw new IllegalArgumentException("FTL file does not exist: " + ftl);
        }
        if (!inputFile.isFile() || !inputFile.canRead()) {
            throw new IllegalArgumentException("Input file must be a readable file: " + input);
        }
        if (!ftlFile.isFile() || !ftlFile.canRead()) {
            throw new IllegalArgumentException("FTL file must be a readable file: " + ftl);
        }
        File outputFile = null;
        if (output != null) {
            outputFile = new File(output).getAbsoluteFile();
            File outputDirectory = outputFile.getParentFile();
            if (!outputDirectory.exists() || !outputDirectory.canWrite()) {
                throw new IllegalArgumentException("The output directory must exist and be writable: "
                        + outputDirectory);
            }
        }
        Locale locale = Locale.getDefault();
        if (loc != null) {
            locale = localeFromString(loc);
        }
        return new Transform(inputFile, ftlFile, outputFile, locale, enc);
    }