This is a beta release of the Winstone Servlet Container. The homepage for this project is at 'http://winstone.sourceforge.net'

Author: Rick Knowles (contact details below)

What is Winstone ?

Winstone is a servlet container that was written out of a desire to provide servlet functionality without the bloat that full J2EE compliance introduces.

It is not intended to be a completely fully functional J2EE style servlet container (by this I mean supporting extraneous APIs unrelated to Servlets, such as JNDI, JavaMail, EJBs, etc) - this is left to Tomcat, Jetty, Resin, JRun, Weblogic et al.

Sometimes you want just a simple servlet container - without all the other junk - that just goes. This is where Winstone is best suited.

The original goals in writing Winstone were:

Why is it called Winstone ?

The short version (because the long version is way too politically incorrect) is as follows:

Winstone is the name of a rather large Jamaican man a friend of mine met one night, while he was out clubbing in the Roppongi area of Tokyo. He (my friend) was a little liquored up at the time, and when Winstone suggested they head to "this really cool club" he knew, he didn't think anything was wrong. It wasn't until Winstone led him down a dark stairwell and dropped his trousers that my friend clued in and ran like hell.

It was too good a story to let die, so I named this project Winstone so that said friend will continue to be reminded of it. Heheheh ....

License

The Web-App DTD files (everything in the src/javax/servlet/resources and src/javax/servlet/jsp/resources folders) are covered by the licenses described at the top of each file (usually as licensed by Sun Microsystems).

As of v0.8.1, all other files are dual-licensed, under either the Lesser GNU Public License (LGPL) as described in LICENSE-LGPL.txt, or the Common Development and Distribution License (CDDL) as decribed in LICENSE-CDDL.txt. Until v0.8, the license used was the GNU Public License (GPL).

The goal of dual-licensing is to make Winstone as attractive as possible to distributors of commercial webapps, while ensuring everyone benefits from any improvements. The CDDL allows free distribution with any commercial applications, while distribution with a GPL licensed webapp is also possible under the LGPL. If you are unclear about which license applies to an application you wish to distribute or sell, please contact me.

Contacting the Author

You can contact me through the Winstone development list at sourceforge (winstone-devel AT lists DOT sourceforge DOT net). If you have any general comments or questions about Winstone please mail me on that list - I'll try to start a faq soon.

I'm open to help from anyone who's willing to help me meet the above goals for Winstone. Just mail me at the list (winstone-devel AT lists DOT sourceforge DOT net)

Using Winstone

If you want to build from source code, you will need to download and install Apache Maven (v1.x). The following instructions assume you have already installed Maven and have the maven shell script in your path (to get Maven, see http://maven.apache.org/).

To build Winstone, unpack the tree:

  tar zxf winstone-src-0.9.10.tar.gz

Then build it:

  cd winstone
  maven clean jar

The winstone.jar file will be in the target directory after the build is complete.

To run it:

  java -jar target/winstone-0.9.10.jar --webroot=<location of webroot> (+ other options)

- OR -

  java -jar target/winstone-0.9.10.jar --warfile=<location of warfile> (+ other options)

- OR -

  java -jar target/winstone-0.9.10.jar --webappsDir=<location of webapps directory> (+ other options)

- OR -

  java -jar target/winstone-0.9.10.jar --hostsDir=<location of hosts directory> (+ other options)

Command-line options:

Syntax:
  java -jar winstone-0.9.10.jar [--option=value] [--option=value] etc

Required options: either --webroot OR --warfile OR --webappsDir OR --hostsDir
   --webroot                = set document root folder.
   --warfile                = set location of warfile to extract from.
   --webappsDir             = set directory for multiple webapps to be deployed from
   --hostsDir               = set directory for name-based virtual hosts to be deployed from

Other options:
   --javaHome               = Override the JAVA_HOME variable
   --toolsJar               = The location of tools.jar (default is JAVA_HOME/lib/tools.jar) 
   --config                 = load configuration properties from here(if supplied).
   --prefix                 = add this prefix to all URLs. (eg http://host/prefix/etc).
   --commonLibFolder        = folder for additional jar files. Default is ./lib
    
   --logfile                = redirect winstone log messages to this file
   --logThrowingLineNo      = show the line no that logged the message (slow). Default is false
   --logThrowingThread      = show the thread that logged the message. Default is false
   --debug                  = set the level of debug msgs (1-9). Default is 5 (INFO level)

   --httpPort               = set the http listening port. -1 to disable, Default is 8080
   --httpListenAddress      = set the http listening address. Default is all interfaces
   --httpDoHostnameLookups  = enable host name lookups on http connections. Default is false
   --httpsPort              = set the https listening port. -1 to disable, Default is disabled
   --httpsListenAddress     = set the https listening address. Default is all interfaces
   --httpsDoHostnameLookups = enable host name lookups on https connections. Default is false
   --httpsKeyStore          = the location of the SSL KeyStore file. Default is ./winstone.ks
   --httpsKeyStorePassword  = the password for the SSL KeyStore file. Default is null
   --httpsKeyManagerType    = the SSL KeyManagerFactory type (eg SunX509, IbmX509). Default is SunX509
   --ajp13Port              = set the ajp13 listening port. -1 to disable, Default is 8009
   --ajp13ListenAddress     = set the ajp13 listening address. Default is all interfaces
   --controlPort            = set the shutdown/control port. -1 to disable, Default disabled

   --handlerCountStartup    = set the no of worker threads to spawn at startup. Default is 5
   --handlerCountMax        = set the max no of worker threads to allow. Default is 300
   --handlerCountMaxIdle    = set the max no of idle worker threads to allow. Default is 50

   --directoryListings      = enable directory lists (true/false). Default is true
   --useJasper              = enable jasper JSP handling (true/false). Default is false
   --useServletReloading    = enable servlet reloading (true/false). Default is false
   --preferredClassLoader   = override the preferred webapp class loader.
   --useInvoker             = enable the servlet invoker (true/false). Default is true
   --invokerPrefix          = set the invoker prefix. Default is /servlet/
   --simulateModUniqueId    = simulate the apache mod_unique_id function. Default is false
   --useSavedSessions       = enables session persistence (true/false). Default is false
   --usage / --help         = show this message
    
Cluster options:
   --useCluster             = enable cluster support (true/false). Default is false
   --clusterClassName       = Set the cluster class to use. Defaults to SimpleCluster class
   --clusterNodes           = a comma separated list of node addresses (IP:ControlPort,IP:ControlPort,etc)

JNDI options:
   --useJNDI                      = enable JNDI support (true/false). Default is false
   --containerJndiClassName       = Set the container wide JNDI manager class to use. Defaults to ContainerJNDIManager
   --webappJndiClassName          = Set the web-app JNDI manager class to use. Defaults to WebAppJNDIManager
   --jndi.resource.<name>         = set the class to be used for the resource marked <name>
   --jndi.param.<name>.<att>      = set an attribute <att> for the resource marked <name>

Security options:
   --realmClassName               = Set the realm class to use for user authentication. Defaults to ArgumentsRealm class

   --argumentsRealm.passwd.<user> = Password for user <user>. (for ArgumentsRealm)
   --argumentsRealm.roles.<user>  = Roles for user <user> (comma-separated) (for ArgumentsRealm)

   --fileRealm.configFile         = File containing users/passwds/roles. Only valid for the FileRealm realm class

Access logging:
   --accessLoggerClassName        = Set the access logger class to use for user authentication. Defaults to disabled
   --simpleAccessLogger.format    = The log format to use. Supports combined/common/resin/custom (SimpleAccessLogger only)
   --simpleAccessLogger.file      = The location pattern for the log file(SimpleAccessLogger only)

Configuration file

You don't really need a config file, but sometimes it's handy to be able to use the same settings each time without running through the command history.

Winstone looks for a config file winstone.properties in the current directory (or in the location specified with --config) at startup. It loads the properties in this file, overrides them with any supplied command line properties, and then starts itself.

This is just intended as a handy feature for people who want to cache regular startup options, rather than using batch files.

Deployment choices

The simplest way to use winstone is with a single webapp. To do this, just supply the warfile or webroot directory as an argument:

If you need to support multiple webapps, use the --webappsDir switch, to which you pass a directory that contains multiple warfiles/webroots.

The directory becomes the prefix name for that webapp (so hello becomes /hello, etc). The directory named ROOT becomes the no-prefix webapp.

So, for example, if you had a directory /usr/local/webapps which contained sub-directories ROOT and test, if you executed java -jar winstone.jar --webappsDir=/usr/local/webapps, you would find that the test folder would act as a webroot for requests prefixed with /test, while other requests would go to the webapp in the ROOT folder

From v0.8, if you need multiple hosts (sometimes called name-based virtual hosting), there is a new option --hostsDir. This acts in a similar way to the --webappsDir switch, but it defines an extra level of sub-directories, the top being a per-host directory and the second a per-webapp directory as with --webappsDir.

The directory name becomes the host name: that is, a directory named "www.blah.com" will only serve requests with the host header www.blah.com, unless it is the default host. If a directory named "default" is found, it becomes the default host. If no default directory is found, the first directory in the list (alphabetically) becomes the default host.

Caveats

As a result of the design goals, there are some things Winstone doesn't do:

Security Warning

If you enable the controlPort, be aware that there is no password protection at all on this port. Anyone who can get access to this port can stop or restart the server. I plan to add some simple authentication to this at some point, but I'll wait until someone asks for it.

The controlPort is disabled by default. If you choose not to enable it, the only way to shut Winstone down is to kill the process (either by Ctrl-C or kill command).

Recent additions

New features in v0.9:

New features in v0.8:

New features in v0.7:

New features in v0.6:

New features in v0.5:

New features in v0.4:

New features in v0.3:

Using Xerces as an XML parser (required for v2.4 webapps)

As part of the upgrade in the servlet specification, the v2.4 incarnation of the web.xml file is validated using XML Schema Documents (XSD) as opposed to Document Type Definitions (DTD). While I still have no idea why such a change was necessary - especially given that DTD validation seems to be more than enough in this case - I did implement it. Perhaps the people on the specification committee might want to give a thought to container size next time round, as this one change multiplies the size of the distribution by five.

Anyway, to use Xerces, you'll need to download the latest Xerces-J parser from here, and copy xercesImpl.jar and xml-apis.jar into a folder somewhere (name it "endorsed"). Putting them in the winstone/lib folder will not work, because they must be in the system endorsed classpath to override the JDK internal XML parser.

Then add -Djava.endorsed.dirs=<endorsed dir name> as a JVM arg to your command line for starting winstone, eg:

  java -Djava.endorsed.dirs=/jdk/endorsed -jar winstone.jar --webroot=...

JSPs (aka using with Jasper)

Winstone supports JSPs using Apache's Jasper JSP compiler. Thanks to a rather clever design by the Jasper team, this was much less work than I expected - well done Jasper guys.

Required steps:

  1. Add --useJasper to your startup command line, since JSPs are disabled by default

  2. Both the v1.x and v2.x versions of Jasper are supported. In order to turn on JSP compilation in Winstone, you'll need to place the following jar files into the lib folder under the current directory (or the folder identified by the --commonLibFolder directive).

    • jasper-compiler.jar, jasper-runtime.jar, ant.jar, jsp-api.jar - Not supplied with Winstone. You can get this from the standard Tomcat binary download location. Just download the latest Tomcat, and copy these three files into the lib folder for Winstone. They will be in the tomcat_home/common/lib folder.
    • commons-logging-api.jar, commons-el.jar (Jasper 2 only) - These are required if you are using Jasper 2.0. You can get them from the tomcat binary distribution or separately from the link below.

    All of these are available from the Jakarta download site

  3. You'll also need tools.jar, and this is handled a little differently. The ant javac compile task needs this to turn the generated .java files into .class files at runtime. You should already have this in the <java_home>/lib folder of your jdk.

    There are two new startup arguments for Winstone --javaHome and --toolsJar. You should only need to set --javaHome to make Jasper work properly. Your startup might look like this:

      java -jar winstone.jar --useJasper \
                         --javaHome=c:\java\jdk1.4.2 \
                         --webroot=...

    Additionally, you can specify the exact location of the toolsJar file like this:

      java -jar winstone.jar --useJasper \
                         --javaHome=c:\java\jdk1.4.2 \
                         --toolsJar=c:\tools.jar \
                         --webroot=...

Newer versions of Jasper seem to use the Eclipse JDT compiler, and therefore don't require tools.jar. You might want to try deploying the jasper related jars yourself - see if you can get it running with just a JRE configuration. Shouldn't be difficult, just a little debugging of which jar files are necessary.

CHANGED: Until v0.9.5, it wasn't necessary to add the jsp-api.jar, because winstone included it's own copy of the JSP API classes. However, the JSP v2.1 spec mandates the use of JDK1.5 generics in the API classes, so in order to continue supplying the API classes, Winstone would have to require JDK1.5 compilation as a minimum. Since a large percentage of people use Winstone for it's small footprint, and PDAs running on older spec JVMs are affected by this, it seemed more reasonable to just drop the JSP API classes and maintain the backwards compatibility.

I disagree with the Expert Group's penchant for trading away backwards compatibility in exchange for spec features that are unnecessary (such as generics and XSD support). But at the end of the day, they call the shots, so I just do what I can to minimize the downsides in practice.

Connecting to Apache

These instructions are for beginners: if you know your way around Apache and Tomcat, you'll know what's going on here.

Download and install Apache for your platform (and obviously Winstone too), then follow these steps:

  1. Download mod_jk.dll/so into the apache modules directory
  2. Add the following to the apache conf file (httpd.conf): 
    LoadModule jk_module modules/mod_jk.dll

<Location "/<Winstone Prefix>/*">
JkMount /* ajp13
</Location>
  3. Create a new file called workers.properties in the apache conf directory, with the following contents 
    worker.list=ajp13
worker.ajp13.port=8009
worker.ajp13.host=localhost
worker.ajp13.type=ajp13
  4. Start up Winstone, ensuring that the --ajp13Port=8009 is in the startup args. It's set to this by default, but it's worth confirming.
  5. Start up Apache and try connecting to your webapp on the apache port, with the Winstone URL prefix. If it doesn't work, try looking at the apache error.log file for hints. If you get hex dumps, mail them to the winstone-devel list, together with any stack traces winstone generated.

Please note this is not an optimal configuration for production uses. This is provided purely for those who need some help to get started. Read the mod_jk documentation with Tomcat for more detailed info. Additionally, Costin Manolache of the Tomcat team suggested I point out that the "jvmRoute" feature (used for managing sticky session behaviour when clustering multiple Winstone's behind a single Apache) is not supported. This may change in the future - we'll see how it goes.

Using Authentication Realms

The process here is almost identical to that of Tomcat (I know this because I used the Tomcat examples webapp to develop against). There are two components - the web.xml component and selecting/configuring an AuthenticationRealm class.

This component is left intentionally fairly simple, and relatively extracted. I'm planning to break the realm and authentication stuff into an optional jar later, since not many webapps I've seen use it.

Cluster support

It should be pointed out in the beginning that the Cluster support currently implemented in Winstone is actually just session sharing. If a request comes to a node in the cluster that doesn't recognise the session ID supplied, that node simply asks the others "Do you know this session ?". If one does know it, it transfers the session to the requesting node, and the requesting node carries on as if it had always had the session in the first place.

If a specific node in the cluster goes offline, so do all the sessions that it was holding. There is no active "push" of sessions to other nodes, so as far as resilience to failure goes, this cluster is fairly weak. The clustering provided here is meant to allow a dumb load balancer to redirect requests randomly across a cluster of Winstone instances without requiring it to be "session sticky".

That said, the configuration is fairly simple. The only information you need is the IP address and control port of at least one other active node in the cluster. Once you have that, add the following options to the command line startup:

java -jar winstone.jar ...< other options > ... \
                       --controlPort=<myControlPort> \
                       --useCluster \
                       --clusterNodes=<IP1:controlPort1>

where IP1 is the IP address of the other node in the cluster, and myControlPort and controlPort1 are the port numbers to use for the control ports of this instance and the other node respectively. Note that it is necessary to actively set the controlPort on this instance, since it is disabled by default.

You would likewise set up the other instance with reciprocal options (ie changing the IPs and controlPort values appropriately.

NOTE: There are some additional requirements on your web application for Clustering of sessions to be successful.

  1. You need to include the <distributable/> element in your web.xml file. This tells Winstone that your webapp is programmed correctly to support clustering. If this is missing, clustering will be disabled.
  2. Any objects you add to the session must implement java.io.Serializable. This is required because Winstone serializes the objects in the session over the controlPort to other nodes, and reconstructs the serialized session at the destination. If you try to put a non-serializable object into the session, Winstone will throw an exception reminding you to make all session objects serializable.

Control port functions/protocol

From v0.5, the behaviour of the control port changes slightly. Due to increased usage of the control port by the clustering function, a rudimentary protocol has been added.

The protocol is very simple. The first byte sent to the server is a flag indicating what type of request is being issued. Beyond that the protocol varies for each request type, but the request type flag options are listed below:

Obviously, unless you're planning to write your own cluster extensions, the only two you will be interested in are the shutdown and reload options. Luckily there is a wrapper class for accessing these functions, named winstone.tools.WinstoneControl. Try the following to get a usage statement:

  java -cp winstone.jar winstone.tools.WinstoneControl

JNDI support

I know that in the introduction I said that Winstone was only going to support the core servlet APIs, but I've since discovered that most people use just a little more than the core servlet API offers. For example, some people use just a JNDI JavaMail session to send administrator error mails, while others want to offer a simple servlet over SSL (and hence need Apache), still others use just a JNDI DataSource to keep a reference to the connection pool.

For this reason I've included a really basic optional JNDI service within Winstone. For the moment, it supports simple operations (such as bind, lookup, rebind, etc) and allows you to store references to environment variables (drawn from the env-entry elements in web.xml and/or command line arguments).

NOTE: JNDI support is disabled by default. It must be enabled using --useJNDI=true

Configuration can be done in two ways:

Additionally, it includes a JDBC DataSource object which can be used as a wrapper around normal JDBC drivers. This is fairly simple for now, but it meets the requirements I mentioned above. Options are as follows:

  1. url (REQUIRED) - JDBC URL (jdbc:mysql://db.widgets.com/db)
  2. driverClassName (REQUIRED) - JDBC Driver name (eg com.mysql.jdbc.Driver)
  3. username - username for database authentication
  4. password - password for database authentication
  5. maxConnections - Maximum number of connections allowed in the pool. Default is 20
  6. maxIdle - Maximum number of idle connections allowed in the pool. Default is 10
  7. startConnections - The number of connections to open the pool with. Deafault is 2
  8. keepAliveSQL - The sql to execute on keep-alive (or checkBeforeGet) operations. Default is empty
  9. checkBeforeGet - If true, executes the keepAliveSQL before any connection is returned from the pool. Default is true if the keepAliveSQL is defined
  10. keepAlivePeriod - Execute the keepAliveSQL on all unused connection every n minutes. Default is disabled
  11. killInactivePeriod - Kills excess unused connections every n minutes. Default is disabled
  12. retryCount - When the pool is maxed out, block and retry n times. Default is 1 retry
  13. retryPeriod - The period (in ms) over which the retry blocks. Default is 1000ms

For example to create a DataSource object at the JNDI location java:/comp/env/jdbc/connPool, use the following command line (or config file) options:

java -jar winstone.jar ...< other options > ... \
                        --useJNDI=true \
                        --jndi.resource.jdbc/connPool=javax.sql.DataSource \
                        --jndi.param.jdbc/connPool.url=jdbc:mysql://db.widgets.com/db \
                        --jndi.param.jdbc/connPool.driverClassName=com.mysql.jdbc.Driver \
                        --jndi.param.jdbc/connPool.username=foo \
                        --jndi.param.jdbc/connPool.password=bar

HTTPS support

Somebody asked me to add HTTPS support, using the JDK 1.4 SSL socket classes, and so I decided to give it a try. It was a lot easier than expected - the API was really nice to use. Unfortunately the hard work seems to be in the configuration, rather than the programming.

I recommend using a shareware tool called KeyStore Explorer, available here. It's much easier than all that messy CLI stuff.

The steps are basically as follows:

  1. Create an empty keystore of type JKS
  2. Generate a key pair (Tools -> Generate Key Pair). I chose RSA 2048 bit, and used "MD5 with RSA" for the algorithm. Set a password and remember it.
  3. Generate a CSR (right click, Generate CSR).
  4. Send the CSR to a Certifying Authority (CA) for processing. I used FreeSSL.com, because it was only US$39 per year.
  5. Once you get the approved certificate back, import it into the key store you were using (Tools -> import CA reply). You should now have only a key pair and a certificate. Save the key store, using the same password you used before.
  6. Start winstone with the following command: 
    java -jar winstone.jar --webroot=<webroot>
                       --httpsPort=443 
                       --httpsKeyStore=<keystore file> 
                       --httpsKeyStorePassword=<password>
  7. Set your hosts file (/etc/hosts or c:/Winnt/system32/drivers/etc/hosts) to point the name on your certificate to 127.0.0.1, then try to browse to https://(name on certificate)/

Access Logging

From v0.8, there's an option to allow access logging. It's disabled by default, but can be enabled by defining a logging implementation class, with --accessLoggerClassName. The class defined must be an implementation of the interface winstone.AccessLogger, and is defined container wide, but instantiated once per webapp.

The supplied logger is called winstone.accesslog.SimpleAccessLogger. It supports Apache style combined/common format logs, as well as Resin format (which is actually just Apache common style plus a user agent). Configuration options are:

For example, to enable Apache Combined style logging to separate files, use a command line like:

java -jar winstone.jar --hostsDir=<vhostsDir>
                           --accessLoggerClassName=winstone.accesslog.SimpleAccessLogger

Or to log just the date and URI for all hosts/webapps to a single file, use a command line like:

java -jar winstone.jar --hostsDir=<vhostsDir>
                       --accessLoggerClassName=winstone.accesslog.SimpleAccessLogger
                       --simpleAccessLogger.format=###date###\ ###uriLine###
                       --simpleAccessLogger.file=/mylogs/access_log.txt

Embedding Winstone

The design of Winstone has always allowed its easy embedding within another application. It's as simple as:

 // at startup
Map args = new HashMap();
args.put("webroot", "<my webroot dir>"); // or any other command line args, eg port
Launcher.initLogger(args);
Launcher winstone = new Launcher(args); // spawns threads, so your application doesn't block

... (your application code)

// before shutdown
winstone.shutdown();

From v0.8 though, there is also the ability to embed in the opposite direction: that is, to embed your warfile into the winstone JAR itself. This allows an all-in-one container plus web-application JAR file to be downloaded, and then unpacked at execution time.

To use this, simply unpack the winstone JAR, and place your WAR file inside the unpacked folder at the top level (with the same parent as the folder named "winstone"). Then rename your WAR file to "embedded.war", and repack the jar as before (make sure to preserve the META-INF and manifest).

Now if you type: "java -jar winstone.jar", your application should automatically deploy as the ROOT web application. Try http://localhost:8080/ to check it out.

If you need to add any default command-line arguments (eg ports or prefixes), you can embed a properties file in exactly the same way, except that the file must be named "embedded.properties".

Session persistence across reboots

From v0.9.5, if you start with --useSavedSessions as an argument, all sessions in the container will be saved to disk after each request, and loaded on container startup. The effect is that sessions will persist across reboots, instead of being lost (which is the default behaviour, or --useSavedSessions=false).

This is useful for development time, if only to prevent you from having to log in to your webapp every time you restart the container. It does however come with a few costs / side effects to think about:

Please give this feature a try if you can, and let me know if you hit any problems. It is still a little green around the edges, so any feedback or corrections will be appreciated.