com.xafero.vee.cmd.MainApp.java Source code

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Here is the source code for com.xafero.vee.cmd.MainApp.java

Source

package com.xafero.vee.cmd;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.StringWriter;

import javax.script.Bindings;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineFactory;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;

import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.CommandLineParser;
import org.apache.commons.cli.DefaultParser;
import org.apache.commons.cli.HelpFormatter;
import org.apache.commons.cli.Option;
import org.apache.commons.cli.Options;

import com.google.common.base.MoreObjects;
import com.xafero.vee.env.Console;
import com.xafero.vee.env.FileSystem;
import com.xafero.vee.env.Media;
import com.xafero.vee.env.Time;
import com.xafero.vee.env.Window;
import com.xafero.vee.env.storage.LocalStorage;
import com.xafero.vee.env.storage.SessionStorage;
import com.xafero.vee.util.Files;
import com.xafero.vee.util.Strings;

public class MainApp {

    private static final String APP_SHORT_NAME = "vee";
    private static final String APP_VER = "0.1-alpha";
    private static final String APP_SRC_URL = "https://github.com/xafero/vee";

    public static void main(String[] args) {
        // Define options
        Option help = new Option("?", "help", false, "print this message");
        Option version = new Option("v", "version", false, "print the version information and exit");
        Option eval = Option.builder("e").desc("evaluate script").argName("file").longOpt("eval").hasArg().build();
        Option list = new Option("l", "list", false, "print all available languages");
        // Collect them
        Options options = new Options();
        options.addOption(help);
        options.addOption(version);
        options.addOption(eval);
        options.addOption(list);
        // If nothing given, nothing will happen
        if (args == null || args.length < 1) {
            printHelp(options);
            return;
        }
        // Parse command line
        try {
            CommandLineParser parser = new DefaultParser();
            CommandLine line = parser.parse(options, args);
            // Work on it
            process(line, options);
        } catch (Throwable e) {
            System.err.printf("Error occurred: %n " + e.getMessage());
        }
    }

    private static void process(CommandLine line, Options options) throws ScriptException, IOException {
        if (line.hasOption('?')) {
            printHelp(options);
            return;
        }
        if (line.hasOption('v')) {
            printVersion();
            return;
        }
        if (line.hasOption('l')) {
            printLanguages();
            return;
        }
        if (line.hasOption('e')) {
            execute(line.getOptionValue('e'));
            return;
        }
        throw new UnsupportedOperationException("Unrecognized option: " + line.getArgList());
    }

    private static void printHelp(Options options) {
        String header = String.format("Ubiquitous scripting in an extensible environment%n%n");
        String footer = String.format("%nPlease report issues at " + APP_SRC_URL);
        HelpFormatter formatter = new HelpFormatter();
        formatter.printHelp(APP_SHORT_NAME, header, options, footer, true);
    }

    private static void printVersion() throws IOException {
        StringWriter writer;
        BufferedWriter out = new BufferedWriter(writer = new StringWriter());
        out.write(APP_SHORT_NAME + " " + APP_VER + " built on JSR 223.");
        out.newLine();
        out.newLine();
        out.write("Copyright (C) 2015 xafero");
        out.newLine();
        out.write("License AGPLv3+: GNU AGPL version 3 or later");
        out.newLine();
        out.write("<https://gnu.org/licenses/agpl.html>.");
        out.newLine();
        out.write("This is free software: you are free to change and redistribute it.");
        out.newLine();
        out.write("There is NO WARRANTY, to the extent permitted by law.");
        out.newLine();
        out.newLine();
        out.write("Please send bug reports and questions to <" + APP_SRC_URL + ">.");
        out.newLine();
        out.flush();
        System.out.print(writer.toString());
    }

    private static void printLanguages() {
        ScriptEngineManager mgr = new ScriptEngineManager();
        for (ScriptEngineFactory factory : mgr.getEngineFactories())
            System.out.println(MoreObjects.toStringHelper("").add("name", factory.getEngineName())
                    .add("version", factory.getEngineVersion())
                    .add("extensions", "[ " + Strings.join(" | ", factory.getExtensions()) + " ]")
                    .add("mimeTypes", "[ " + Strings.join(" | ", factory.getMimeTypes()) + " ]")
                    .add("aliases", "[ " + Strings.join(" | ", factory.getNames()) + " ]")
                    .add("language", factory.getLanguageName() + " " + factory.getLanguageVersion())
                    .omitNullValues().toString().replace(", ", String.format(", %n ")));
    }

    private static void execute(String fileName) throws FileNotFoundException, ScriptException {
        File file = (new File(fileName)).getAbsoluteFile();
        if (!file.exists())
            throw new FileNotFoundException("There's no file named '" + file + "'!");
        String extension = Files.getExtension(file);
        ScriptEngineManager mgr = new ScriptEngineManager();
        ScriptEngine engine = mgr.getEngineByExtension(extension);
        Bindings env = engine.createBindings();
        inject(env, file);
        try {
            Object result = engine.eval(new FileReader(file), env);
            if (result != null)
                System.out.println(result.toString());
        } catch (ScriptException e) {
            throw e;
        }
    }

    private static void inject(Bindings env, File file) {
        env.put("window", new Window());
        env.put("console", new Console(file.getName()));
        env.put("fs", new FileSystem());
        env.put("media", new Media());
        env.put("time", new Time());
        env.put("localStorage", new LocalStorage());
        env.put("sessionStorage", new SessionStorage());
    }
}