org.directwebremoting.impl.ContainerUtil Maven / Gradle / Ivy
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/*
* Copyright 2005 Joe Walker
*
* 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.directwebremoting.impl;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;
import java.util.StringTokenizer;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.xml.parsers.ParserConfigurationException;
import org.directwebremoting.Container;
import org.directwebremoting.ServerContextFactory.ServerContextBuilder;
import org.directwebremoting.WebContextFactory.WebContextBuilder;
import org.directwebremoting.dwrp.DefaultConverterManager;
import org.directwebremoting.dwrp.HtmlCallMarshaller;
import org.directwebremoting.dwrp.PlainCallMarshaller;
import org.directwebremoting.extend.AccessControl;
import org.directwebremoting.extend.AjaxFilterManager;
import org.directwebremoting.extend.Configurator;
import org.directwebremoting.extend.ConverterManager;
import org.directwebremoting.extend.Creator;
import org.directwebremoting.extend.CreatorManager;
import org.directwebremoting.extend.DebugPageGenerator;
import org.directwebremoting.extend.DwrConstants;
import org.directwebremoting.extend.Handler;
import org.directwebremoting.extend.PageNormalizer;
import org.directwebremoting.extend.Remoter;
import org.directwebremoting.extend.ScriptSessionManager;
import org.directwebremoting.extend.ServerLoadMonitor;
import org.directwebremoting.servlet.AboutHandler;
import org.directwebremoting.servlet.AuthHandler;
import org.directwebremoting.servlet.DwrWebContextFilter;
import org.directwebremoting.servlet.EngineHandler;
import org.directwebremoting.servlet.HtmlCallHandler;
import org.directwebremoting.servlet.HtmlPollHandler;
import org.directwebremoting.servlet.IndexHandler;
import org.directwebremoting.servlet.InterfaceHandler;
import org.directwebremoting.servlet.PathConstants;
import org.directwebremoting.servlet.PlainCallHandler;
import org.directwebremoting.servlet.PlainPollHandler;
import org.directwebremoting.servlet.TestHandler;
import org.directwebremoting.servlet.UrlProcessor;
import org.directwebremoting.servlet.UtilHandler;
import org.directwebremoting.servlet.WebworkUtilHandler;
import org.directwebremoting.util.LocalUtil;
import org.directwebremoting.util.Logger;
import org.xml.sax.SAXException;
/**
* An abstraction of all the common servlet operations that are required to host
* a DWR service that depends on the servlet spec.
* It would be good to have a base class for all servlet operations, however
* lack of MI prevents us from doing this.
* @author Joe Walker [joe at getahead dot ltd dot uk]
*/
public class ContainerUtil
{
/**
* Create a {@link DefaultContainer}, allowing users to upgrade to a child
* of DefaultContainer using an {@link ServletConfig} init parameter of
* org.directwebremoting.Container. Note that while the
* parameter name is the classname of {@link Container}, currently the only
* this can only be used to create children that inherit from
* {@link DefaultContainer}. This restriction may be relaxed in the future.
* Unlike {@link #setupDefaultContainer(DefaultContainer, ServletConfig)},
* this method does not call any setup methods.
* @param servletConfig The source of init parameters
* @return An unsetup implementaion of DefaultContainer
* @throws ServletException If the specified class could not be found
* @see ServletConfig#getInitParameter(String)
*/
public static DefaultContainer createDefaultContainer(ServletConfig servletConfig) throws ServletException
{
try
{
String typeName = servletConfig.getInitParameter(Container.class.getName());
if (typeName == null)
{
return new DefaultContainer();
}
log.debug("Using alternate Container implementation: " + typeName);
Class type = LocalUtil.classForName(typeName);
return (DefaultContainer) type.newInstance();
}
catch (Exception ex)
{
throw new ServletException(ex);
}
}
/**
* Setup a {@link DefaultContainer}.
* Using {@link #createDefaultContainer(ServletConfig)} followed by
* {@link #setupFromServletConfig(DefaultContainer, ServletConfig)} before
* calling {@link DefaultContainer#setupFinished()}.
* @param container The container to configure
* @param servletConfig The source of init parameters
* @throws InstantiationException If we can't instantiate a bean
* @throws IllegalAccessException If we have access problems creating a bean
*/
public static void setupDefaultContainer(DefaultContainer container, ServletConfig servletConfig) throws InstantiationException, IllegalAccessException
{
setupDefaults(container, servletConfig);
setupFromServletConfig(container, servletConfig);
container.setupFinished();
}
/**
* Take a DefaultContainer and setup the default beans
* @param container The container to configure
* @param servletConfig The source of init parameters
* @throws InstantiationException If we can't instantiate a bean
* @throws IllegalAccessException If we have access problems creating a bean
*/
public static void setupDefaults(DefaultContainer container, ServletConfig servletConfig) throws InstantiationException, IllegalAccessException
{
container.addParameter(AccessControl.class.getName(), DefaultAccessControl.class.getName());
container.addParameter(ConverterManager.class.getName(), DefaultConverterManager.class.getName());
container.addParameter(CreatorManager.class.getName(), DefaultCreatorManager.class.getName());
container.addParameter(UrlProcessor.class.getName(), UrlProcessor.class.getName());
container.addParameter(WebContextBuilder.class.getName(), DefaultWebContextBuilder.class.getName());
container.addParameter(ServerContextBuilder.class.getName(), DefaultServerContextBuilder.class.getName());
container.addParameter(AjaxFilterManager.class.getName(), DefaultAjaxFilterManager.class.getName());
container.addParameter(Remoter.class.getName(), DefaultRemoter.class.getName());
container.addParameter(DebugPageGenerator.class.getName(), DefaultDebugPageGenerator.class.getName());
container.addParameter(PlainCallMarshaller.class.getName(), PlainCallMarshaller.class.getName());
container.addParameter(HtmlCallMarshaller.class.getName(), HtmlCallMarshaller.class.getName());
container.addParameter(PlainPollHandler.class.getName(), PlainPollHandler.class.getName());
container.addParameter(HtmlPollHandler.class.getName(), HtmlPollHandler.class.getName());
container.addParameter(ScriptSessionManager.class.getName(), DefaultScriptSessionManager.class.getName());
container.addParameter(PageNormalizer.class.getName(), DefaultPageNormalizer.class.getName());
if (servletConfig.getServletContext().getServerInfo().startsWith("jetty-6"))
{
container.addParameter(ServerLoadMonitor.class.getName(), ThreadDroppingServerLoadMonitor.class.getName());
}
else
{
container.addParameter(ServerLoadMonitor.class.getName(), DefaultServerLoadMonitor.class.getName());
}
// Mapping handlers to URLs
createUrlMapping(container, "/index.html", "indexHandlerUrl", IndexHandler.class);
createUrlMapping(container, "/engine.js", "engineHandlerUrl", EngineHandler.class);
createUrlMapping(container, "/util.js", "utilHandlerUrl", UtilHandler.class);
createUrlMapping(container, "/auth.js", "authHandlerUrl", AuthHandler.class);
createUrlMapping(container, "/webwork/DWRActionUtil.js", "webworkUtilHandlerUrl", WebworkUtilHandler.class);
createUrlMapping(container, "/about", "aboutHandlerUrl", AboutHandler.class);
createUrlMapping(container, "/test/", "testHandlerUrl", TestHandler.class);
createUrlMapping(container, "/interface/", "interfaceHandlerUrl", InterfaceHandler.class);
// The Poll and Call URLs can not be changed easily because they are
// referenced from engine.js. Maybe one day this would be a good
// extension
createUrlMapping(container, "/call/plaincall/", "plainCallHandlerUrl", PlainCallHandler.class);
createUrlMapping(container, "/call/plainpoll/", "plainPollHandlerUrl", PlainPollHandler.class);
createUrlMapping(container, "/call/htmlcall/", "htmlCallHandlerUrl", HtmlCallHandler.class);
createUrlMapping(container, "/call/htmlpoll/", "htmlPollHandlerUrl", HtmlPollHandler.class);
}
/**
* Creates entries in the {@link Container} so 2 lookups are possible.
*
* - You can find a {@link Handler} for a URL. Used by {@link UrlProcessor}
*
- You can inject (or lookup) the URL assigned to a {@link Handler}
*
* @param container The container to create the entries in
* @param url The URL of the new {@link Handler}
* @param propertyName The property name (for injection and lookup)
* @param handler The class of Handler
* @throws InstantiationException From {@link DefaultContainer#addParameter(Object, Object)}
* @throws IllegalAccessException From {@link DefaultContainer#addParameter(Object, Object)}
*/
public static void createUrlMapping(DefaultContainer container, String url, String propertyName, Class handler) throws InstantiationException, IllegalAccessException
{
container.addParameter(PathConstants.URL_PREFIX + url, handler.getName());
container.addParameter(propertyName, url);
}
/**
* Take a DefaultContainer and setup the default beans
* @param container The container to configure
* @param servletConfig The servlet configuration (null to ignore)
* @throws InstantiationException If we can't instantiate a bean
* @throws IllegalAccessException If we have access problems creating a bean
*/
public static void setupFromServletConfig(DefaultContainer container, ServletConfig servletConfig) throws InstantiationException, IllegalAccessException
{
Enumeration en = servletConfig.getInitParameterNames();
while (en.hasMoreElements())
{
String name = (String) en.nextElement();
String value = servletConfig.getInitParameter(name);
container.addParameter(name, value);
}
}
/**
* Make some changes to the ServletContext so {@link DwrWebContextFilter}
* can find the Container etc.
* @param context The servlet context
* @param config The servlet configuration
* @param container The container to save in the ServletContext
* @param webContextBuilder The WebContextBuilder to save
* @param servlet The Servlet to save
*/
public static void prepareForWebContextFilter(ServletContext context, ServletConfig config, Container container, WebContextBuilder webContextBuilder, HttpServlet servlet)
{
context.setAttribute(Container.class.getName(), container);
context.setAttribute(WebContextBuilder.class.getName(), webContextBuilder);
context.setAttribute(ServletConfig.class.getName(), config);
context.setAttribute(HttpServlet.class.getName(), servlet);
}
/**
* Configure using the system dwr.xml from within the JAR file.
* @param container The container to configure
* @throws ParserConfigurationException If the config file parse fails
* @throws IOException If the config file read fails
* @throws SAXException If the config file parse fails
*/
public static void configureFromSystemDwrXml(Container container) throws IOException, ParserConfigurationException, SAXException
{
DwrXmlConfigurator system = new DwrXmlConfigurator();
system.setClassResourceName(DwrConstants.FILE_DWR_XML);
system.configure(container);
}
/**
* Configure using the users dwr.xml that sits next in WEB-INF
* @param container The container to configure
* @throws ParserConfigurationException If the config file parse fails
* @throws IOException If the config file read fails
* @throws SAXException If the config file parse fails
*/
public static void configureFromDefaultDwrXml(Container container) throws IOException, ParserConfigurationException, SAXException
{
DwrXmlConfigurator local = new DwrXmlConfigurator();
local.setServletResourceName(DwrConstants.DEFAULT_DWR_XML);
local.configure(container);
}
/**
* Add configurators from init params to the end of the list of
* configurators.
* @param container The container to configure
* @param servletConfig The source of init parameters
* @return true if any Configurators were read
* @throws SAXException If the config file parse fails
* @throws ParserConfigurationException If the config file parse fails
* @throws IOException If the config file read fails
*/
public static boolean configureFromInitParams(Container container, ServletConfig servletConfig) throws IOException, ParserConfigurationException, SAXException
{
Enumeration en = servletConfig.getInitParameterNames();
boolean foundConfig = false;
while (en.hasMoreElements())
{
String name = (String) en.nextElement();
String value = servletConfig.getInitParameter(name);
// if the init param starts with "config" then try to load it
if (name.startsWith(INIT_CONFIG))
{
foundConfig = true;
StringTokenizer st = new StringTokenizer(value, "\n,");
while (st.hasMoreTokens())
{
String fileName = st.nextToken().trim();
DwrXmlConfigurator local = new DwrXmlConfigurator();
local.setServletResourceName(fileName);
local.configure(container);
}
}
else if (name.equals(INIT_CUSTOM_CONFIGURATOR))
{
foundConfig = true;
try
{
Configurator configurator = (Configurator) LocalUtil.classNewInstance(INIT_CUSTOM_CONFIGURATOR, value, Configurator.class);
configurator.configure(container);
log.debug("Loaded config from: " + value);
}
catch (Exception ex)
{
log.warn("Failed to start custom configurator", ex);
}
}
}
return foundConfig;
}
/**
* Annotations must not break 1.3, so we use reflection to create an
* org.directwebremoting.annotations.AnnotationsConfigurator
* and the catch all sorts of random exceptions for the benefit of
* Websphere.
* @param container The container to configure
* @return true if the configuration worked.
*/
public static boolean configureFromAnnotations(Container container)
{
try
{
Class annotationCfgClass = LocalUtil.classForName("org.directwebremoting.annotations.AnnotationsConfigurator");
Configurator configurator = (Configurator) annotationCfgClass.newInstance();
configurator.configure(container);
log.debug("Java5 AnnotationsConfigurator enabled");
return true;
}
catch (UnsupportedClassVersionError ex)
{
// This will happen in JDK 1.4 and below
return false;
}
catch (ClassNotFoundException ex)
{
// This will happen when run in an IDE without the java5 tree
log.warn("AnnotationsConfigurator is missing. Are you running from within an IDE?");
return false;
}
catch (Exception ex)
{
// This happens if there is a bug in AnnotationsConfigurator
log.warn("Failed to start annotations", ex);
return false;
}
catch (Throwable ex)
{
if (ex.getClass().getName().equals(UnsupportedClassVersionError.class.getName()))
{
log.error("Caught impossible Throwable", ex);
return false;
}
else if (ex.getClass().getName().equals(LinkageError.class.getName()))
{
log.error("Caught impossible Throwable", ex);
return false;
}
else if (ex instanceof Error)
{
log.fatal("Rethrowing Error:" + ex);
throw (Error) ex;
}
else
{
// This can't happen: We've handled all Exceptions, and
// Errors, so we can't get to execute this code.
log.error("Ilogical catch state", ex);
return false;
}
}
}
/**
* Allow all the configurators to have a go at the container in turn
* @param container The container to configure
* @param configurators A list of configurators to run against the container
*/
public static void configure(Container container, List configurators)
{
// Allow all the configurators to have a go
for (Iterator it = configurators.iterator(); it.hasNext();)
{
Configurator configurator = (Configurator) it.next();
log.debug("** Adding config from " + configurator);
configurator.configure(container);
}
}
/**
* Run all the default configuration options on a Container
* @param container The container to configure
* @param servletConfig The source of init parameters
* @throws SAXException If the config file parse fails
* @throws ParserConfigurationException If the config file parse fails
* @throws IOException If the config file read fails
*/
public static void configureContainerFully(Container container, ServletConfig servletConfig) throws IOException, ParserConfigurationException, SAXException
{
configureFromSystemDwrXml(container);
boolean foundConfig = configureFromInitParams(container, servletConfig);
// The default dwr.xml file that sits by web.xml
boolean skip = Boolean.valueOf(servletConfig.getInitParameter(INIT_SKIP_DEFAULT)).booleanValue();
IOException delayedIOException = null;
if (!foundConfig && !skip)
{
try
{
configureFromDefaultDwrXml(container);
}
catch (IOException ex)
{
// This is fatal unless we are on JDK5+ AND using annotations
delayedIOException = ex;
}
}
if (!configureFromAnnotations(container))
{
log.debug("Java5 AnnotationsConfigurator disabled");
if (delayedIOException != null)
{
throw delayedIOException;
}
}
}
/**
* If helps some situations if people can get at the container by looking
* in the servlet context, under some name.
* The name is specified in an initParameter.
* @param container The container to publish
* @param servletConfig Source of initParams to dictate publishing and contexts to publish to
*/
public static void publishContainer(Container container, ServletConfig servletConfig)
{
ServletContext servletContext = servletConfig.getServletContext();
String publishName = servletConfig.getInitParameter(INIT_PUBLISH_CONTAINER);
if (publishName != null)
{
servletContext.setAttribute(publishName, container);
}
List containers = (List) servletContext.getAttribute(ATTRIBUTE_CONTAINER_LIST);
if (containers == null)
{
containers = new ArrayList();
}
containers.add(container);
servletContext.setAttribute(ATTRIBUTE_CONTAINER_LIST, containers);
}
/**
* Get a list of all known Containers for the given {@link ServletContext}
* @param servletContext The context in which {@link Container}s are stored.
* @return a list of published {@link Container}s.
*/
public static List getAllPublishedContainers(ServletContext servletContext)
{
List containers = (List) servletContext.getAttribute(ATTRIBUTE_CONTAINER_LIST);
if (containers == null)
{
containers = new ArrayList();
}
return containers;
}
/**
* Internal use only.
* If we detect that the server is being shutdown then we want to kill
* any reverse ajax threads.
* @param containers The list of containers to look for ServerLoadMonitors in
* @param title What causes this (for debug purposes)
*/
public static void shutdownServerLoadMonitorsInContainerList(List containers, String title)
{
if (containers == null || containers.size() == 0)
{
log.debug("No containers to shutdown for: " + title);
return;
}
log.debug("Shutting down containers for: " + title);
for (Iterator it = containers.iterator(); it.hasNext();)
{
Container container = (Container) it.next();
ServerLoadMonitor monitor = (ServerLoadMonitor) container.getBean(ServerLoadMonitor.class.getName());
monitor.shutdown();
}
}
/**
* Create a bunch of debug information about a container
* @param container The container to print debug information about
*/
public static void debugConfig(Container container)
{
if (log.isDebugEnabled())
{
// Container level debug
log.debug("Container");
log.debug(" Type: " + container.getClass().getName());
Collection beanNames = container.getBeanNames();
for (Iterator it = beanNames.iterator(); it.hasNext();)
{
String name = (String) it.next();
Object object = container.getBean(name);
if (object instanceof String)
{
log.debug(" Param: " + name + " = " + object + " (" + object.getClass().getName() + ")");
}
else
{
log.debug(" Bean: " + name + " = " + object + " (" + object.getClass().getName() + ")");
}
}
// AccessControl debugging
AccessControl accessControl = (AccessControl) container.getBean(AccessControl.class.getName());
log.debug("AccessControl");
log.debug(" Type: " + accessControl.getClass().getName());
// AjaxFilterManager debugging
AjaxFilterManager ajaxFilterManager = (AjaxFilterManager) container.getBean(AjaxFilterManager.class.getName());
log.debug("AjaxFilterManager");
log.debug(" Type: " + ajaxFilterManager.getClass().getName());
// ConverterManager debugging
ConverterManager converterManager = (ConverterManager) container.getBean(ConverterManager.class.getName());
log.debug("ConverterManager");
log.debug(" Type: " + converterManager.getClass().getName());
// CreatorManager debugging
CreatorManager creatorManager = (CreatorManager) container.getBean(CreatorManager.class.getName());
log.debug("CreatorManager");
log.debug(" Type: " + creatorManager.getClass().getName());
Collection creatorNames = creatorManager.getCreatorNames();
for (Iterator it = creatorNames.iterator(); it.hasNext();)
{
String creatorName = (String) it.next();
Creator creator = creatorManager.getCreator(creatorName);
log.debug(" Creator: " + creatorName + " = " + creator + " (" + creator.getClass().getName() + ")");
}
}
}
/**
* Init parameter: Set a dwr.xml config file.
* This is only a prefix since we might have more than 1 config file.
*/
public static final String INIT_CONFIG = "config";
/**
* Init parameter: Skip reading the default config file if none are specified.
*/
public static final String INIT_SKIP_DEFAULT = "skipDefaultConfig";
/**
* Init parameter: If we are doing Servlet.log logging, to what level?
*/
public static final String INIT_LOGLEVEL = "logLevel";
/**
* Init parameter: Should we publish the {@link Container} to the servlet
* context, and if so, under what name?
*/
public static final String INIT_PUBLISH_CONTAINER = "publishContainerAs";
/**
* Init parameter: If you wish to use a custom configurator, place its
* class name here
*/
public static final String INIT_CUSTOM_CONFIGURATOR = "customConfigurator";
/**
* The name under which we publish all {@link Container}s.
*/
public static final String ATTRIBUTE_CONTAINER_LIST = "org.directwebremoting.ContainerList";
/**
* The log stream
*/
private static final Logger log = Logger.getLogger(ContainerUtil.class);
}