EDIT

/**

 * Copyright (C) 2009 EDIT

 * European Distributed Institute of Taxonomy

 * http://www.e-taxonomy.eu

 *

 * The contents of this file are subject to the Mozilla Public License Version 1.1

 * See LICENSE.TXT at the top of this package for the full license terms.

 */

package eu.etaxonomy.cdm.server;

import static eu.etaxonomy.cdm.server.AssumedMemoryRequirements.KB;

import static eu.etaxonomy.cdm.server.CommandOptions.CONTEXT_PATH_PREFIX;

import static eu.etaxonomy.cdm.server.CommandOptions.DATASOURCES_FILE;

import static eu.etaxonomy.cdm.server.CommandOptions.FORCE_SCHEMA_UPDATE;

import static eu.etaxonomy.cdm.server.CommandOptions.HELP;

import static eu.etaxonomy.cdm.server.CommandOptions.HTTP_PORT;

import static eu.etaxonomy.cdm.server.CommandOptions.JMX;

import static eu.etaxonomy.cdm.server.CommandOptions.WEBAPP;

import static eu.etaxonomy.cdm.server.CommandOptions.WEBAPP_CLASSPATH;

import static eu.etaxonomy.cdm.server.CommandOptions.WIN32SERVICE;

import java.io.BufferedReader;

import java.io.File;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.FilenameFilter;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.lang.management.ManagementFactory;

import java.lang.reflect.InvocationTargetException;

import java.net.MalformedURLException;

import java.net.URL;

import java.net.URLClassLoader;

import java.util.ArrayList;

import java.util.List;

import java.util.Properties;

import java.util.jar.Attributes;

import java.util.jar.JarFile;

import java.util.jar.Manifest;

import java.util.regex.Pattern;

import org.apache.commons.cli.CommandLine;

import org.apache.commons.cli.CommandLineParser;

import org.apache.commons.cli.GnuParser;

import org.apache.commons.cli.HelpFormatter;

import org.apache.commons.cli.ParseException;

import org.apache.commons.io.FileUtils;

import org.apache.commons.io.FilenameUtils;

import org.apache.log4j.Logger;

import org.apache.tomcat.SimpleInstanceManager;

import org.apache.tomcat.util.scan.StandardJarScanner;

import org.eclipse.jetty.apache.jsp.JettyJasperInitializer;

import org.eclipse.jetty.jmx.MBeanContainer;

import org.eclipse.jetty.plus.annotation.ContainerInitializer;

import org.eclipse.jetty.security.HashLoginService;

import org.eclipse.jetty.server.Handler;

import org.eclipse.jetty.server.Server;

import org.eclipse.jetty.server.ServerConnector;

import org.eclipse.jetty.server.handler.ContextHandler;

import org.eclipse.jetty.server.handler.ContextHandlerCollection;

import org.eclipse.jetty.servlet.ServletContextHandler;

import org.eclipse.jetty.util.component.AbstractLifeCycle;

import org.eclipse.jetty.util.log.Log;

import org.eclipse.jetty.webapp.WebAppClassLoader;

import org.eclipse.jetty.webapp.WebAppContext;

import eu.etaxonomy.cdm.server.instance.CdmInstance;

import eu.etaxonomy.cdm.server.instance.Configuration;

import eu.etaxonomy.cdm.server.instance.InstanceManager;

import eu.etaxonomy.cdm.server.instance.SharedAttributes;

import eu.etaxonomy.cdm.server.instance.Status;

import eu.etaxonomy.cdm.server.logging.LoggingConfigurator;

import eu.etaxonomy.cdm.server.win32service.Win32Service;

/**

 * A bootstrap class for starting Jetty Runner using an embedded war.

 *

 * @version $Revision$

 */

public final class Bootloader {

    private static final Logger logger = Logger.getLogger(Bootloader.class);

    //private static final String DEFAULT_WARFILE = "target/";

    private static final String DATASOURCE_BEANDEF_FILE = "datasources.xml";

    private static final String REALM_PROPERTIES_FILE = "cdm-server-realm.properties";

    private static final String USERHOME_CDM_LIBRARY_PATH = System.getProperty("user.home")+File.separator+".cdmLibrary"+File.separator;

    private static final String TMP_PATH = USERHOME_CDM_LIBRARY_PATH + "server" + File.separator;

    private static final String APPLICATION_NAME = "CDM Server";

    private static final String WAR_POSTFIX = ".war";

    private static final String CDM_WEBAPP = "cdm-webapp";

    private static final String CDM_WEBAPP_VERSION = "cdm-webapp.version";

    private static final String DEFAULT_WEBAPP_WAR_NAME = "default-webapp";

    private static final File DEFAULT_WEBAPP_TEMP_FOLDER = new File(TMP_PATH + DEFAULT_WEBAPP_WAR_NAME);

    private static final File CDM_WEBAPP_TEMP_FOLDER = new File(TMP_PATH + CDM_WEBAPP);

    private static final String SPRING_PROFILES_ACTIVE = "spring.profiles.active";

    private static final String VERSION_PROPERTIES_FILE = "version.properties";

    private final InstanceManager instanceManager = new InstanceManager(new File(USERHOME_CDM_LIBRARY_PATH, DATASOURCE_BEANDEF_FILE));

    public List<CdmInstance> getCdmInstances() {

        return instanceManager.getInstances();

    }

    public InstanceManager getInstanceManager(){

        return instanceManager;

    }

    private File cdmRemoteWebAppFile = null;

    private File defaultWebAppFile = null;

    private String webAppClassPath = null;

    /**

     * The contextPathPrefix is expected to be normalized:

     * it ends with a slash and starts not with a slash character

     */

    private String contextPathPrefix = "";

    private Server server = null;

    private final ContextHandlerCollection contexts = new ContextHandlerCollection();

    private final LoggingConfigurator loggingConfigurator = new LoggingConfigurator();

    private CommandLine cmdLine;

    private boolean isRunningFromSource;

    private boolean isRunningfromTargetFolder;

    private boolean isRunningFromWarFile;

    private String cdmlibServicesVersion = "";

    private String cdmlibServicesLastModified = "";

    /* thread save singleton implementation */

    private static Bootloader bootloader = new Bootloader();

    private Bootloader() {}

    /**

     * @return the thread save singleton instance of the Bootloader

     */

    public synchronized static Bootloader getBootloader(){

        return bootloader;

    }

    /* end of singleton implementation */

    public int writeStreamTo(final InputStream input, final OutputStream output, int bufferSize) throws IOException {

        int available = Math.min(input.available(), 256 * KB);

        byte[] buffer = new byte[Math.max(bufferSize, available)];

        int answer = 0;

        int count = input.read(buffer);

        while (count >= 0) {

            output.write(buffer, 0, count);

            answer += count;

            count = input.read(buffer);

        }

        return answer;

    }

    public void parseCommandOptions(String[] args) throws ParseException {

        CommandLineParser parser = new GnuParser();  //TODO using DefaultParser instead currently still throws "org.apache.commons.cli.UnrecognizedOptionException: Unrecognized option: -httpPort=8080"

        cmdLine = parser.parse( CommandOptions.getOptions(), args );

        // print the help message

        if(cmdLine.hasOption(HELP.getOpt())){

            HelpFormatter formatter = new HelpFormatter();

            formatter.setWidth(200);

            formatter.printHelp( "java .. ", CommandOptions.getOptions() );

            System.exit(0);

        }

    }

    /**

     * Finds the named war file either in the resources known to the class loader

     * or in a target folder if the bootloader is started from within a maven project.

     * Once found the war file is copied to the temp folder defined by {@link TMP_PATH}.

     *

     * The war file can optionally be unpacked.

     *

     * @param warName

     * @param unpack

     *  unzip the war file after extraction

     * @return

     * @throws IOException

     * @throws FileNotFoundException

     */

    private File extractWar(String warName, boolean unpack) throws IOException, FileNotFoundException {

        ClassLoader classLoader = Thread.currentThread().getContextClassLoader();

        String warFileName = warName + WAR_POSTFIX;

        // 1. find in classpath

        URL resource = classLoader.getResource(warFileName);

        if (resource == null) {

            logger.error("Could not find the " + warFileName + " on classpath!");

            File pomxml = new File("pom.xml");

            if(pomxml.exists()){

                logger.info("will try find the war in target folder of maven project");

                // 2. try finding in target folder of maven project

                File warFile = new File("target" + File.separator + warFileName);

                logger.debug("looking for war file at " + warFile.getAbsolutePath());

                if (warFile.canRead()) {

                    resource = warFile.toURI().toURL();

                    logger.info("Success! Using war file from " + resource.toString());

                } else {

                    logger.error("Also could not find the " + warFileName + " in maven project, try excuting 'mvn install'");

                }

            }

        }

        if (resource == null) {

            // no way finding the war file :-(

            System.exit(1);

        }

        File extractedWarFile = new File(TMP_PATH, warName + "-" + WAR_POSTFIX);

        logger.info("Extracting " + resource + " to " + extractedWarFile + " ...");

        writeStreamTo(resource.openStream(), new FileOutputStream(extractedWarFile), 8 * KB);

        if(!unpack) {

            // return the war file

            return extractedWarFile;

        } else {

            // unpack the archive

            File explodedWebApp = null;

            try {

                logger.info("Unpacking " + extractedWarFile);

                explodedWebApp  = unzip(extractedWarFile);

                // get the 'Bundle-Version' and 'Bnd-LastModified' properties of the

                // manifest file in the cdmlib services jar

                if(explodedWebApp != null && explodedWebApp.isDirectory()) {

                    // generate the webapp lib dir path

                    String warLibDirAbsolutePath = explodedWebApp.getAbsolutePath() +

                            File.separator +

                            "WEB-INF" +

                            File.separator +

                            "lib";

                    File warLibDir = new File(warLibDirAbsolutePath);

                    if(warLibDir.exists()) {

                        // get the cdmlib-services jar

                        File [] files = warLibDir.listFiles(new FilenameFilter() {

                            @Override

                            public boolean accept(File dir, String name) {

                                return name.startsWith("cdmlib-services") && name.endsWith(".jar");

                            }

                        });

                        if(files != null && files.length > 0) {

                            // get the relevant info from the jar manifest

                            JarFile jarFile = new JarFile(files[0]);

                            Manifest manifest = jarFile.getManifest();

                            Attributes attributes = manifest.getMainAttributes();

                            // from the OSGI spec the LastModified value is " the number of milliseconds

                            // since midnight Jan. 1, 1970 UTC with the condition that a change must

                            // always result in a higher value than the previous last modified time

                            // of any bundle"

                            cdmlibServicesVersion = attributes.getValue("Bundle-Version");

                            logger.warn("cdmlib-services version : " + cdmlibServicesVersion);

                            cdmlibServicesLastModified = attributes.getValue("Bnd-LastModified");

                            logger.warn("cdmlib-services last modified timestamp : " + cdmlibServicesLastModified);

                            if(cdmlibServicesVersion == null || cdmlibServicesLastModified == null) {

                                throw new IllegalStateException("Invalid cdmlib-services manifest file");

                            }

                        } else {

                            throw new IllegalStateException("cdmlib-services jar not found ");

                        }

                    }

                }

            } catch (IOException e) {

                logger.error("extractWar() - Unziping of war file " + explodedWebApp + " failed. Will return the war file itself instead of the extracted folder.", e);

            }

            return explodedWebApp;

        }

    }

    public String getCdmlibServicesVersion() {

        return cdmlibServicesVersion;

    }

    public String getCdmlibServicesLastModified() {

        return cdmlibServicesLastModified;

    }

    private File unzip(File extractWar) throws IOException {

        UnzipUtility unzip = new UnzipUtility();

        String targetFolderName = FilenameUtils.getBaseName(extractWar.getName());

        File destDirectory = new File(TMP_PATH + File.separator + targetFolderName);

        unzip.unzip(extractWar, destDirectory);

        return destDirectory;

    }

    /**

     * MAIN METHOD

     *

     * @param args

     * @throws Exception

     */

    public static void main(String[] args) throws Exception {

        Bootloader bootloader = Bootloader.getBootloader();

        bootloader.parseCommandOptions(args);

        bootloader.startServer();

    }

    public void startServer() throws IOException,

            FileNotFoundException, Exception, InterruptedException {

        logger.info("Starting " + APPLICATION_NAME);

        logger.info("Using  " + System.getProperty("user.home") + " as home directory. Can be specified by -Duser.home=<FOLDER>");

        //assure TMP_PATH exists and clean it up

        File tempDir = new File(TMP_PATH);

        if(!tempDir.exists() && !tempDir.mkdirs()){

            logger.error("Error creating temporary directory for webapplications " + tempDir.getAbsolutePath());

            System.exit(-1);

        } else {

            if(FileUtils.deleteQuietly(tempDir)){

                tempDir.mkdirs();

                logger.info("Old webapplications successfully cleared");

            }

        }

        tempDir = null;

        // WEBAPP options

        //   prepare web application files to run either from war files (production mode)

        //   or from source (development mode)

        if(cmdLine.hasOption(WEBAPP.getOpt())){

            cdmRemoteWebAppFile = new File(cmdLine.getOptionValue(WEBAPP.getOpt()));

            if(cdmRemoteWebAppFile.isDirectory()){

                logger.info("using user defined web application folder: " + cdmRemoteWebAppFile.getAbsolutePath());

            } else {

                logger.info("using user defined warfile: " + cdmRemoteWebAppFile.getAbsolutePath());

            }

            updateServerRunMode();

            // load the default-web-application from source if running in development mode mode

            if(isRunningFromWarFile){

                defaultWebAppFile = extractWar(DEFAULT_WEBAPP_WAR_NAME, false);

            } else {

                defaultWebAppFile = new File("./src/main/webapp");

            }

            if(isRunningFromSource){

                if(cmdLine.hasOption(WEBAPP_CLASSPATH.getOpt())){

                    String classPathOption = cmdLine.getOptionValue(WEBAPP_CLASSPATH.getOpt());

                    normalizeClasspath(classPathOption);

                }

            }

        } else {

            // read version number

            String version = readCdmRemoteVersion();

            cdmRemoteWebAppFile = extractWar(CDM_WEBAPP + "-" + version, true);

            defaultWebAppFile = extractWar(DEFAULT_WEBAPP_WAR_NAME, false);

        }

        // HTTP Port

        int httpPort = 8080;

        if(cmdLine.hasOption(HTTP_PORT.getOpt())){

            try {

               httpPort = Integer.parseInt(cmdLine.getOptionValue(HTTP_PORT.getOpt()));

               logger.info(HTTP_PORT.getOpt()+" set to "+cmdLine.getOptionValue(HTTP_PORT.getOpt()));

           } catch (NumberFormatException e) {

               logger.error("Supplied portnumber is not an integer");

               System.exit(-1);

           }

        }

        if(cmdLine.hasOption(DATASOURCES_FILE.getOpt())){

             File datasourcesFile = new File(cmdLine.getOptionValue(DATASOURCES_FILE.getOpt()));

             if(datasourcesFile.canRead()) {

                instanceManager.setDatasourcesFile(datasourcesFile);

            } else {

                logger.error("File set as " + DATASOURCES_FILE.getOpt()

                        + " (" + cmdLine.getOptionValue(DATASOURCES_FILE.getOpt())

                        + ") is not readable.");

            }

         }

        if(cmdLine.hasOption(CONTEXT_PATH_PREFIX.getOpt())){

            String cppo  = cmdLine.getOptionValue(CONTEXT_PATH_PREFIX.getOpt());

            if(cppo.equals("/")) {

                this.contextPathPrefix = "";

            } else {

                Pattern pattern = Pattern.compile("^/*(.*?)/*$");

                String replacement = "$1";

                this.contextPathPrefix = pattern.matcher(cppo).replaceAll(replacement) + "/";

            }

        }

        verifySystemResources();

         // load the configured instances for the first time

        instanceManager.reLoadInstanceConfigurations();

        if(System.getProperty(SPRING_PROFILES_ACTIVE) == null){

            logger.info(SPRING_PROFILES_ACTIVE + " is undefined, and will be set to : \"remoting\"");

            System.setProperty(SPRING_PROFILES_ACTIVE, "remoting");

        }

        // in jetty 9 currently each connector uses

        // 2 threads -  1 to select for IO activity and 1 to accept new connections.

        // there fore we need to add 2 to the number of cores

//        QueuedThreadPool threadPool = new QueuedThreadPool(JvmManager.availableProcessors() +  + 200);

//        server = new Server(threadPool);

        server = new Server();

        jdk8MemleakFixServer();

        loggingConfigurator.configureServer();

        server.addLifeCycleListener(instanceManager);

        ServerConnector connector = new ServerConnector(server);

        connector.setPort(httpPort);

        logger.info("http port: " + connector.getPort());

        server.addConnector(connector );

        org.eclipse.jetty.webapp.Configuration.ClassList classlist = org.eclipse.jetty.webapp.Configuration.ClassList.setServerDefault(server);

        classlist.addAfter(

                org.eclipse.jetty.webapp.FragmentConfiguration.class.getName(),

                org.eclipse.jetty.plus.webapp.EnvConfiguration.class.getName(),

                org.eclipse.jetty.plus.webapp.PlusConfiguration.class.getName()

                );

        classlist.addBefore(

                org.eclipse.jetty.webapp.JettyWebXmlConfiguration.class.getName(),

                org.eclipse.jetty.annotations.AnnotationConfiguration.class.getName());

        // JMX support

        if(cmdLine.hasOption(JMX.getOpt())){

            logger.info("adding JMX support ...");

            MBeanContainer mBeanContainer = new MBeanContainer(ManagementFactory.getPlatformMBeanServer());

            server.addEventListener(mBeanContainer);

            server.addBean(Log.getLog());

        }

        if(cmdLine.hasOption(WIN32SERVICE.getOpt())){

            Win32Service win32Service = new Win32Service();

            win32Service.setServer(server);

            server.setStopAtShutdown(true);

            server.addBean(win32Service);

        }

        WebAppContext defaultWebappContext = createDefaultWebappContext();

        contexts.addHandler(defaultWebappContext);

        logger.info("setting contexts ...");

        server.setHandler(contexts);

        logger.info("starting jetty ...");

//        try {

            server.start();

//        } catch(org.springframework.beans.BeansException e){

//        	Throwable rootCause = null;

//        	while(e.getCause() != null){

//        		rootCause = e.getCause();

//        	}

//        	if(rootCause != null && rootCause.getClass().getSimpleName().equals("InvalidCdmVersionException")){

//

//        		logger.error("rootCause ----------->" + rootCause.getMessage());

////        		for(CdmInstanceProperties props : configAndStatus){

////        			if(props.getDataSourceName())

////        		}

//        	}

//        }

        if(cmdLine.hasOption(WIN32SERVICE.getOpt())){

            logger.info("jetty has started as win32 service");

        } else {

            server.join();

            logger.info(APPLICATION_NAME+" stopped.");

            System.exit(0);

        }

    }

    private WebAppContext createDefaultWebappContext() throws FileNotFoundException {

        // add default servlet context

        logger.info("preparing default WebAppContext");

        WebAppContext defaultWebappContext = new WebAppContext();

        setWebApp(defaultWebappContext, defaultWebAppFile);

        // JSP

        //

        // configuring jsp according to http://eclipse.org/jetty/documentation/current/configuring-jsp.html

        // from example http://eclipse.org/jetty/documentation/current/embedded-examples.html#embedded-webapp-jsp

        // Set the ContainerIncludeJarPattern so that jetty examines these

        // container-path jars for tlds, web-fragments etc.

        // If you omit the jar that contains the jstl .tlds, the jsp engine will

        // scan for them instead.

        defaultWebappContext.setAttribute(

                "org.eclipse.jetty.server.webapp.ContainerIncludeJarPattern",

                ".*/[^/]*servlet-api-[^/]*\\.jar$|.*/javax.servlet.jsp.jstl-.*\\.jar$|.*/[^/]*taglibs.*\\.jar$" );

        defaultWebappContext.setAttribute("org.eclipse.jetty.containerInitializers", jspInitializers());

        defaultWebappContext.setAttribute(InstanceManager.class.getName(), new SimpleInstanceManager());

        // Context path

        //

        defaultWebappContext.setContextPath("/" + (contextPathPrefix.isEmpty() ? "" : contextPathPrefix.substring(0, contextPathPrefix.length() - 1)));

        logger.info("defaultWebapp (manager) context path:" + defaultWebappContext.getContextPath());

        defaultWebappContext.setTempDirectory(DEFAULT_WEBAPP_TEMP_FOLDER);

        // configure security context

        // see for reference * http://docs.codehaus.org/display/JETTY/Realms

        //                   * http://wiki.eclipse.org/Jetty/Starting/Porting_to_Jetty_7

        HashLoginService loginService = new HashLoginService();

        File realmConfigFile = new File(USERHOME_CDM_LIBRARY_PATH + REALM_PROPERTIES_FILE);

        if(!realmConfigFile.canRead()) {

            throw new FileNotFoundException("Unable to find or read the realm file at " + realmConfigFile.getPath());

        }

        loginService.setConfig(realmConfigFile.getPath());

        defaultWebappContext.getSecurityHandler().setLoginService(loginService);

        // Set Classloader of Context to be sane (needed for JSTL)

        // JSP requires a non-System classloader, this simply wraps the

        // embedded System classloader in a way that makes it suitable

        // for JSP to use

        ClassLoader jspClassLoader = new URLClassLoader(new URL[0], this.getClass().getClassLoader());

        defaultWebappContext.setClassLoader(this.getClass().getClassLoader());

        // JspStarter to solve java.lang.IllegalStateException: No org.apache.tomcat.InstanceManager set in ServletContext problems

        // when running not from within the IDE (see https://issues.apache.org/jira/browse/KNOX-1639)

        defaultWebappContext.addBean(new JspStarter(defaultWebappContext));

        return defaultWebappContext;

    }

    /**

     * jdk8 memleak workaround: disable url caching

     *  see https://dev.e-taxonomy.eu/redmine/issues/5048

     *

     * @throws IOException

     * @throws MalformedURLException

     */

    private void jdk8MemleakFixServer() throws IOException, MalformedURLException {

        String javaVersion = System.getProperty("java.version");

        if(javaVersion.startsWith("1.8")){

            logger.info("jdk8 memory leak fix: jdk8 detected (" + javaVersion + ") disabling url caching to avoid memory leak.");

            org.eclipse.jetty.util.resource.Resource.setDefaultUseCaches(false);

            File tmpio = new File(System.getProperty("java.io.tmpdir"));

            tmpio.toURI().toURL().openConnection().setDefaultUseCaches(false);

        } else {

            logger.info("jdk8 memory leak fix: unaffected jdk " + javaVersion + " detected");

        }

    }

    private void jdk8MemleakFixInstance(ClassLoader classLoader, CdmInstance instance) throws IOException, MalformedURLException, ClassNotFoundException, InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, NoSuchMethodException, SecurityException {

        String javaVersion = System.getProperty("java.version");

        if(javaVersion.startsWith("1.8")){

            logger.info("jdk8 memory leak fix for " + instance.getName() + ": jdk8 detected (" + javaVersion + ") disabling url caching to avoid memory leak.");

            Class<?> fileClass = classLoader.loadClass("java.io.File");

            File tmpio = (File) fileClass.getConstructor(String.class).newInstance("java.io.tmpdir");

            tmpio.toURI().toURL().openConnection().setDefaultUseCaches(false);

        } else {

            logger.info("jdk8 memory leak fix, " + instance.getName() + "unaffected jdk " + javaVersion + " detected");

        }

    }

    /**

     * @param classpath

     */

    private void normalizeClasspath(String classpath) {

        StringBuilder classPathBuilder = new StringBuilder((int) (classpath.length() * 1.2));

        String[] cpEntries = classpath.split("[\\:]");

        for(String cpEntry : cpEntries){

            classPathBuilder.append(',');

//            if(cpEntry.endsWith(".jar")){

//                classPathBuilder.append("jar:");

//            }

            classPathBuilder.append(cpEntry);

        }

        webAppClassPath = classPathBuilder.toString();

    }

    public String readCdmRemoteVersion() throws IOException {

        String version = "cdmlib version unreadable";

        InputStream versionInStream = Bootloader.class.getClassLoader().getResourceAsStream(VERSION_PROPERTIES_FILE);

        if (versionInStream != null){

            Properties versionProperties = new Properties();

            versionProperties.load(versionInStream);

            version = versionProperties.getProperty(CDM_WEBAPP_VERSION, version);

        }

        return version;

    }

    /**

    * Ensure the jsp engine is initialized correctly

    */

    private List<ContainerInitializer> jspInitializers()

    {

        JettyJasperInitializer sci = new JettyJasperInitializer();

        ContainerInitializer initializer = new ContainerInitializer(sci, null);

        List<ContainerInitializer> initializers = new ArrayList<ContainerInitializer>();

        initializers.add(initializer);

        return initializers;

    }

    /**

     * JspStarter for embedded ServletContextHandlers

     *

     * This is added as a bean that is a jetty LifeCycle on the ServletContextHandler.

     * This bean's doStart method will be called as the ServletContextHandler starts,

     * and will call the ServletContainerInitializer for the jsp engine.

     *

     */

    public static class JspStarter extends AbstractLifeCycle implements ServletContextHandler.ServletContainerInitializerCaller {

      JettyJasperInitializer sci;

      ServletContextHandler context;

      public JspStarter (ServletContextHandler context) {

        this.sci = new JettyJasperInitializer();

        this.context = context;

        this.context.setAttribute("org.apache.tomcat.JarScanner", new StandardJarScanner());

      }

      @Override

      protected void doStart() throws Exception

      {

        ClassLoader old = Thread.currentThread().getContextClassLoader();

        Thread.currentThread().setContextClassLoader(context.getClassLoader());

        try

        {

          sci.onStartup(null, context.getServletContext());

          super.doStart();

        }

        finally

        {

          Thread.currentThread().setContextClassLoader(old);

        }

      }

    }

    private void verifySystemResources() {

        OsChecker osChecker = new OsChecker();

        if(osChecker.isLinux()){

            try {

                Process p = Runtime.getRuntime().exec(new String[] { "bash", "-c", "ulimit -n" });

                BufferedReader in = new BufferedReader(new InputStreamReader(p.getInputStream()));

                String line;

                StringBuilder response = new StringBuilder();

                     while ((line = in.readLine()) != null) {

                         response.append(line);

                     }

               logger.info("OS Limit (Linux): maximum number of open files: " + response);

            } catch (IOException e) {

                // TODO Auto-generated catch block

                e.printStackTrace();

            }

        } else {

            logger.info("verifySystemResources only implemented for linux");

        }

    }

    /**

     * Adds a new WebAppContext to the contexts of the running jetty instance.

     * <ol>

     * <li>Initialize WebAppContext:

     * <ol>

     * <li>set context path</li>

     * <li>set tmp directory</li>

     * <li>bind JndiDataSource</li>

     * <li>set web app context attributes</li>

     * <li>create and setup individual classloader for the instance</li>

     * </ol>

     * </li>

     * <li>

     * finally add the new webappcontext to the contexts of the jetty instance</li>

     * </ol>

     *

     * @param instance

     * @return the instance given as parameter of null in case the instance has

     *         {@link Status.#disabled} or if it is already added.

     * @throws IOException

     */

    public WebAppContext addCdmInstanceContext(CdmInstance instance) throws IOException {

        Configuration conf = instance.getConfiguration();

        if(!instance.isEnabled()){

            logger.info(conf.getInstanceName() + " is disabled, possibly due to JVM memory limitations");

            return null;

        }

        if(getContextFor(conf) != null){

            logger.info(conf.getInstanceName() + " is alreaddy added to the contexts - skipping");

            return null;

        }

        instance.setStatus(Status.initializing);

        logger.info("preparing WebAppContext for '"+ conf.getInstanceName() + "'");

        WebAppContext cdmWebappContext = new WebAppContext();

        cdmWebappContext.setContextPath(constructContextPath(conf));

        logger.info("contextPath: " + cdmWebappContext.getContextPath());

        // set persistTempDirectory to prevent jetty from creating and deleting this directory for each instance,

        // since this behaviour can cause conflicts during parallel start up  of instances.

        cdmWebappContext.setPersistTempDirectory(true);

//        if(!instance.bindJndiDataSource()){

//            // a problem with the datasource occurred skip this webapp

//            cdmWebappContext = null;

//            logger.error("a problem with the datasource occurred -> skipping /" + conf.getInstanceName());

//            instance.setStatus(Status.error);

//            return cdmWebappContext;

//        }

        cdmWebappContext.setInitParameter(SharedAttributes.ATTRIBUTE_DATASOURCE_NAME, conf.getInstanceName());

        cdmWebappContext.setInitParameter(SharedAttributes.ATTRIBUTE_JDBC_JNDI_NAME, conf.getJdbcJndiName());

        if(cmdLine.hasOption(FORCE_SCHEMA_UPDATE.getOpt())){

            cdmWebappContext.setInitParameter(SharedAttributes.ATTRIBUTE_FORCE_SCHEMA_UPDATE, "true");

        }

        setWebApp(cdmWebappContext, getCdmRemoteWebAppFile());

        if( isRunningFromSource ){

            /*

             * when running the webapp from {projectpath} src/main/webapp we

             * must assure that each web application is using it's own

             * classloader thus we tell the WebAppClassLoader where the

             * dependencies of the webapplication can be found. Otherwise

             * the system classloader would load these resources.

             */

            WebAppClassLoader classLoader = new WebAppClassLoader(cdmWebappContext);

            if(webAppClassPath != null){

                logger.info("Running cdm-webapp from source folder: Adding class path supplied by option '-" +  WEBAPP_CLASSPATH.getOpt() +" =" + webAppClassPath +"'  to WebAppClassLoader");

                classLoader.addClassPath(webAppClassPath);

                try {

                    jdk8MemleakFixInstance(classLoader, instance);

                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException

                        | IllegalArgumentException | InvocationTargetException | NoSuchMethodException

                        | SecurityException e) {

                    logger.error("Cannot apply jdk8MemleakFix to instance " + instance, e);

                }

            } else {

                throw new RuntimeException("Classpath cdm-webapp for missing while running cdm-webapp from source folder. Please supplied cdm-server option '-" +  WEBAPP_CLASSPATH.getOpt() +"");

            }

            cdmWebappContext.setClassLoader(classLoader);

        }

        contexts.addHandler(loggingConfigurator.configureWebApp(cdmWebappContext, instance));

        instance.setWebAppContext(cdmWebappContext);

        cdmWebappContext.addLifeCycleListener(instance);

        instance.setStatus(Status.stopped);

        return cdmWebappContext;

    }

    /**

     * @param conf

     * @return

     */

    public String constructContextPath(Configuration conf) {

        return "/" + contextPathPrefix + conf.getInstanceName();

    }

    /**

     * Removes the given instance from the contexts. If the instance is running

     * at the time of calling this method it will be stopped first.

     * The JndiDataSource and the webapplicationContext will be released and removed.

     *

     * @param instance the instance to be removed

     *

     * @throws Exception in case stopping the instance fails

     */

    public void removeCdmInstanceContext(CdmInstance instance) throws Exception {

        if(instance.getWebAppContext() != null){

            if(instance.getWebAppContext().isRunning()){

                try {

                    instance.getWebAppContext().stop();

                } catch (Exception e) {

                    instance.getProblems().add("Error while stopping instance: " + e.getMessage());

                    throw e;

                }

            }

            contexts.removeHandler(instance.getWebAppContext());

            instance.releaseWebAppContext();

        } else  {

            // maybe something went wrong before, try to find the potentially lost

            // contexts directly in the server

            ContextHandler handler = getContextFor(instance.getConfiguration());

            if(handler != null){

                contexts.removeHandler(handler);

            }

        }

        instance.unbindJndiDataSource();

    }

    /**

     * Sets the webapp specified by the <code>webApplicationResource</code> to

     * the given <code>context</code>.

     *

     * @param context

     * @param webApplicationResource the resource can either be a directory containing

     * a Java web application or *.war file.

     *

     */

    private void setWebApp(WebAppContext context, File webApplicationResource) {

        if(webApplicationResource.isDirectory()){

            context.setResourceBase(webApplicationResource.getAbsolutePath());

            logger.debug("setting directory " + webApplicationResource.getAbsolutePath() + " as webapplication");

        } else {

            context.setWar(webApplicationResource.getAbsolutePath());

            logger.debug("setting war file " + webApplicationResource.getAbsolutePath() + " as webapplication");

        }

    }

    private void updateServerRunMode() {

        String webappPathNormalized = cdmRemoteWebAppFile.getAbsolutePath().replace('\\', '/');

        isRunningFromSource =  webappPathNormalized.endsWith("src/main/webapp");

        isRunningfromTargetFolder = webappPathNormalized.endsWith("cdm-webapp/target/cdmserver");

        isRunningFromWarFile = !(isRunningFromSource || isRunningfromTargetFolder);