groovymain.java

大名鼎鼎的java动态脚本语言。已经通过了sun的认证

        main.isScriptFile = !line.hasOption('e');
        main.debug = line.hasOption('d');
        main.conf.setDebug(main.debug);
        main.processFiles = line.hasOption('p') || line.hasOption('n');
        main.autoOutput = line.hasOption('p');
        main.editFiles = line.hasOption('i');
        if (main.editFiles) {
            main.backupExtension = line.getOptionValue('i');
        }

        if (main.isScriptFile) {
            if (args.isEmpty())
                throw new ParseException("neither -e or filename provided");

            main.script = (String) args.remove(0);
            if (main.script.endsWith(".java"))
                throw new ParseException("error: cannot compile file with .java extension: " + main.script);
        } else {
            main.script = line.getOptionValue('e');
        }

        main.processSockets = line.hasOption('l');
        if (main.processSockets) {
            String p = line.getOptionValue('l', "1960"); // default port to listen to
            main.port = new Integer(p).intValue();
        }
        main.args = args;

        return main.run();
    }


    /**
     * Run the script.
     */
    private boolean run() {
        try {
            if (processSockets) {
                processSockets();
            } else if (processFiles) {
                processFiles();
            } else {
                processOnce();
            }
            return true;
        } catch (CompilationFailedException e) {
            System.err.println(e);
            return false;
        } catch (Throwable e) {
            if (e instanceof InvokerInvocationException) {
                InvokerInvocationException iie = (InvokerInvocationException) e;
                e = iie.getCause();
            }
            System.err.println("Caught: " + e);
            if (debug) {
                e.printStackTrace();
            } else {
                StackTraceElement[] stackTrace = e.getStackTrace();
                for (int i = 0; i < stackTrace.length; i++) {
                    StackTraceElement element = stackTrace[i];
                    String fileName = element.getFileName();
                    if (fileName!=null && !fileName.endsWith(".java")) {
                        System.err.println("\tat " + element);
                    }
                }
            }
            return false;
        }
    }

    /**
     * Process Sockets.
     */
    private void processSockets() throws CompilationFailedException, IOException {
        GroovyShell groovy = new GroovyShell(conf);
        //check the script is currently valid before starting a server against the script
        if (isScriptFile) {
            groovy.parse(new FileInputStream(huntForTheScriptFile(script)));
        } else {
            groovy.parse(script);
        }
        new GroovySocketServer(groovy, isScriptFile, script, autoOutput, port);
    }

    /**
     * Hunt for the script file, doesn't bother if it is named precisely.
     *
     * Tries in this order:
     * - actual supplied name
     * - name.groovy
     * - name.gvy
     * - name.gy
     * - name.gsh
     */
    public File huntForTheScriptFile(String scriptFileName) {
        File scriptFile = new File(scriptFileName);
        String[] standardExtensions = {".groovy",".gvy",".gy",".gsh"};
        int i = 0;
        while (i < standardExtensions.length && !scriptFile.exists()) {
            scriptFile = new File(scriptFileName + standardExtensions[i]);
            i++;
        }
        // if we still haven't found the file, point back to the originally specified filename
        if (!scriptFile.exists()) {
            scriptFile = new File(scriptFileName);
        }
        return scriptFile;
    }

    /**
     * Process the input files.
     */
    private void processFiles() throws CompilationFailedException, IOException {
        GroovyShell groovy = new GroovyShell(conf);

        Script s = null;

        if (isScriptFile) {
            s = groovy.parse(huntForTheScriptFile(script));
        } else {
            s = groovy.parse(script, "main");
        }

        if (args.isEmpty()) {
            BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
            PrintWriter writer = new PrintWriter(System.out);

            try {
                processReader(s, reader, writer);
            } finally {
                reader.close();
                writer.close();
            }

        } else {
            Iterator i = args.iterator();
            while (i.hasNext()) {
                String filename = (String) i.next();
                File file = huntForTheScriptFile(filename);
                processFile(s, file);
            }
        }
    }

    /**
     * Process a single input file.
     *
     * @param s    the script to execute.
     * @param file the input file.
     */
    private void processFile(Script s, File file) throws IOException {
        if (!file.exists())
            throw new FileNotFoundException(file.getName());

        if (!editFiles) {
            BufferedReader reader = new BufferedReader(new FileReader(file));
            try {
                PrintWriter writer = new PrintWriter(System.out);
                processReader(s, reader, writer);
                writer.flush();
            } finally {
                reader.close();
            }
        } else {
            File backup = null;
            if (backupExtension == null) {
                backup = File.createTempFile("groovy_", ".tmp");
                backup.deleteOnExit();
            } else {
                backup = new File(file.getPath() + backupExtension);
            }
            backup.delete();
            if (!file.renameTo(backup))
                throw new IOException("unable to rename " + file + " to " + backup);

            BufferedReader reader = new BufferedReader(new FileReader(backup));
            try {
                PrintWriter writer = new PrintWriter(new FileWriter(file));
                try {
                    processReader(s, reader, writer);
                } finally {
                    writer.close();
                }
            } finally {
                reader.close();
            }
        }
    }

    /**
     * Process a script against a single input file.
     *
     * @param s      script to execute.
     * @param reader input file.
     * @param pw     output sink.
     */
    private void processReader(Script s, BufferedReader reader, PrintWriter pw) throws IOException {
        String line = null;
        s.setProperty("out", pw);
        while ((line = reader.readLine()) != null) {
            s.setProperty("line", line);
            Object o = s.run();

            if (autoOutput) {
                pw.println(o);
            }
        }
    }
    
    private static ClassLoader getLoader(ClassLoader cl) {
        if (cl!=null) return cl;
        cl = Thread.currentThread().getContextClassLoader();
        if (cl!=null) return cl;
        cl = GroovyMain.class.getClassLoader();
        if (cl!=null) return cl;
        return null;
    }
    
    /**
     * Process the standard, single script with args.
     */
    private void processOnce() throws CompilationFailedException, IOException {
        GroovyShell groovy = new GroovyShell(conf);

        if (isScriptFile)
            groovy.run(huntForTheScriptFile(script), args);
        else
            groovy.run(script, "script_from_command_line", args);
    }
}