Groovy example source code file (Main.groovy)

This example Groovy source code file (Main.groovy) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Groovy tags/keywords

ansidetector, ansidetector, groovysh, groovysh, io, io, jdk, jvm, messagesource, noexitsecuritymanager, securitymanager, string, string, threading, threads, warning

The Groovy Main.groovy source code

/*
 * Copyright 2003-2011 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.codehaus.groovy.tools.shell

import org.codehaus.groovy.tools.shell.util.HelpFormatter
import org.codehaus.groovy.tools.shell.util.Logger
import org.codehaus.groovy.tools.shell.util.MessageSource
import org.codehaus.groovy.tools.shell.util.NoExitSecurityManager
import java.util.concurrent.Callable
import org.fusesource.jansi.Ansi
import org.fusesource.jansi.AnsiConsole
import jline.Terminal

/**
 * Main CLI entry-point for <tt>groovysh.
 *
 * @version $Id: Main.groovy 22399 2011-06-25 04:02:14Z paulk $
 * @author <a href="mailto:jason@planet57.com">Jason Dillon
 */
class Main
{
    static {
        // Install the system adapters
        AnsiConsole.systemInstall()

        // Register jline ansi detector
        Ansi.setDetector(new AnsiDetector())
    }

    private static final MessageSource messages = new MessageSource(Main.class)

    static void main(final String[] args) {
        IO io = new IO()
        Logger.io = io

        def cli = new CliBuilder(usage : 'groovysh [options] [...]', formatter: new HelpFormatter(), writer: io.out)

        cli.classpath(messages['cli.option.classpath.description'])
        cli.cp(longOpt: 'classpath', messages['cli.option.cp.description'])
        cli.h(longOpt: 'help', messages['cli.option.help.description'])
        cli.V(longOpt: 'version', messages['cli.option.version.description'])
        cli.v(longOpt: 'verbose', messages['cli.option.verbose.description'])
        cli.q(longOpt: 'quiet', messages['cli.option.quiet.description'])
        cli.d(longOpt: 'debug', messages['cli.option.debug.description'])
        cli.C(longOpt: 'color', args: 1, argName: 'FLAG', optionalArg: true, messages['cli.option.color.description'])
        cli.D(longOpt: 'define', args: 1, argName: 'NAME=VALUE', messages['cli.option.define.description'])
        cli.T(longOpt: 'terminal', args: 1, argName: 'TYPE', messages['cli.option.terminal.description'])

        def options = cli.parse(args)

        if (options.h) {
            cli.usage()
            System.exit(0)
        }

        if (options.V) {
            io.out.println(messages.format('cli.info.version', GroovySystem.version))
            System.exit(0)
        }

        if (options.hasOption('T')) {
            def type = options.getOptionValue('T')
            setTerminalType(type)
        }

        if (options.hasOption('D')) {
            def values = options.getOptionValues('D')

            values.each {
                setSystemProperty(it as String)
            }
        }

        if (options.v) {
            io.verbosity = IO.Verbosity.VERBOSE
        }

        if (options.d) {
            io.verbosity = IO.Verbosity.DEBUG
        }

        if (options.q) {
            io.verbosity = IO.Verbosity.QUIET
        }

        if (options.hasOption('C')) {
            def value = options.getOptionValue('C')
            setColor(value)
        }

        def code

        // Add a hook to display some status when shutting down...
        addShutdownHook {
            //
            // FIXME: We need to configure JLine to catch CTRL-C for us... Use gshell-io's InputPipe
            //

            if (code == null) {
                // Give the user a warning when the JVM shutdown abnormally, normal shutdown
                // will set an exit code through the proper channels

                io.err.println()
                io.err.println('@|red WARNING:|@ Abnormal JVM shutdown detected')
            }

            io.flush()
        }

        // Boot up the shell... :-)
        Groovysh shell = new Groovysh(io)

        SecurityManager psm = System.getSecurityManager()
        System.setSecurityManager(new NoExitSecurityManager())

        try {
            code = shell.run(options.arguments() as String[])
        }
        finally {
            System.setSecurityManager(psm)
        }

        // Force the JVM to exit at this point, since shell could have created threads or
        // popped up Swing components that will cause the JVM to linger after we have been
        // asked to shutdown

        System.exit(code)
    }

    static void setTerminalType(String type) {
        assert type != null
        
        type = type.toLowerCase();

        switch (type) {
            case 'auto':
                type = null;
                break;

            case 'unix':
                type = 'jline.UnixTerminal'
                break

            case 'win':
            case 'windows':
                type = 'jline.WindowsTerminal'
                break

            case 'false':
            case 'off':
            case 'none':
                type = 'jline.UnsupportedTerminal'
                // Disable ANSI, for some reason UnsupportedTerminal reports ANSI as enabled, when it shouldn't
                Ansi.enabled = false
                break;
        }

        if (type != null) {
            System.setProperty('jline.terminal', type)
        }
    }

    static void setColor(value) {
        if (value == null) {
            value = true // --color is the same as --color=true
        }
        else {
            value = Boolean.valueOf(value).booleanValue(); // For JDK 1.4 compat
        }

        Ansi.enabled = value
    }

    static void setSystemProperty(final String nameValue) {
        String name
        String value

        if (nameValue.indexOf('=') > 0) {
            def tmp = nameValue.split('=', 2)
            name = tmp[0]
            value = tmp[1]
        }
        else {
            name = nameValue
            value = Boolean.TRUE.toString()
        }

        System.setProperty(name, value)
    }
}

class AnsiDetector
    implements Callable<Boolean>
{
    public Boolean call() throws Exception {
        return Terminal.getTerminal().isANSISupported()
    }
}