/*
* JBoss, Home of Professional Open Source.
* Copyright 2011, Red Hat, Inc., and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.as.webservices.util;
import static org.jboss.as.webservices.WSMessages.MESSAGES;
import java.io.File;
import java.lang.reflect.InvocationTargetException;
import javax.naming.NamingException;
import javax.servlet.Servlet;
import org.apache.catalina.Container;
import org.apache.catalina.Host;
import org.apache.catalina.LifecycleException;
import org.apache.catalina.Loader;
import org.apache.catalina.Wrapper;
import org.apache.catalina.core.StandardContext;
import org.apache.catalina.startup.ContextConfig;
import org.apache.tomcat.InstanceManager;
import org.jboss.as.web.deployment.WebCtxLoader;
import org.jboss.msc.service.StartException;
/**
* WebAppController allows for automatically starting/stopping a webapp (servlet) depending on the actual need. This is useful
* for WS deployments needing a given utility servlet to be up (for instance the port component link servlet)
*
* @author alessio.soldano@jboss.com
* @since 02-Dec-2011
*/
public class WebAppController {
private Host host;
private String contextRoot;
private String urlPattern;
private String serverTempDir;
private String servletClass;
private ClassLoader classloader;
private volatile StandardContext ctx;
private int count = 0;
public WebAppController(Host host, String servletClass, ClassLoader classloader, String contextRoot, String urlPattern,
String serverTempDir) {
this.host = host;
this.contextRoot = contextRoot;
this.urlPattern = urlPattern;
this.serverTempDir = serverTempDir;
this.classloader = classloader;
this.servletClass = servletClass;
}
public synchronized int incrementUsers() throws StartException {
if (count == 0) {
try {
ctx = startWebApp(host);
} catch (Exception e) {
throw new StartException(e);
}
}
return count++;
}
public synchronized int decrementUsers() {
if (count == 0) {
throw new IllegalStateException();
}
count--;
if (count == 0) {
try {
stopWebApp(ctx);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
return count;
}
private StandardContext startWebApp(Host host) throws Exception {
StandardContext context = new StandardContext();
try {
context.setPath(contextRoot);
context.addLifecycleListener(new ContextConfig());
File docBase = new File(serverTempDir, contextRoot);
if (!docBase.exists()) {
docBase.mkdirs();
}
context.setDocBase(docBase.getPath());
final Loader loader = new WebCtxLoader(classloader);
loader.setContainer(host);
context.setLoader(loader);
context.setInstanceManager(new LocalInstanceManager());
final int j = servletClass.indexOf(".");
final String servletName = j < 0 ? servletClass : servletClass.substring(j + 1);
final Class<?> clazz = classloader.loadClass(servletClass);
final Wrapper wsfsWrapper = context.createWrapper();
wsfsWrapper.setName(servletName);
wsfsWrapper.setServlet((Servlet) clazz.newInstance());
wsfsWrapper.setServletClass(servletClass);
context.addChild(wsfsWrapper);
context.addServletMapping(urlPattern, servletName);
host.addChild(context);
context.create();
} catch (Exception e) {
throw MESSAGES.createContextPhaseFailed(e);
}
try {
context.start();
} catch (LifecycleException e) {
throw MESSAGES.startContextPhaseFailed(e);
}
return context;
}
private void stopWebApp(StandardContext context) throws Exception {
try {
Container container = context.getParent();
container.removeChild(context);
context.stop();
} catch (LifecycleException e) {
throw MESSAGES.stopContextPhaseFailed(e);
}
try {
context.destroy();
} catch (Exception e) {
throw MESSAGES.destroyContextPhaseFailed(e);
}
}
private static class LocalInstanceManager implements InstanceManager {
LocalInstanceManager() {
}
@Override
public Object newInstance(String className) throws IllegalAccessException, InvocationTargetException, NamingException,
InstantiationException, ClassNotFoundException {
return Class.forName(className).newInstance();
}
@Override
public Object newInstance(String fqcn, ClassLoader classLoader) throws IllegalAccessException,
InvocationTargetException, NamingException, InstantiationException, ClassNotFoundException {
return Class.forName(fqcn, false, classLoader).newInstance();
}
@Override
public Object newInstance(Class<?> c) throws IllegalAccessException, InvocationTargetException, NamingException,
InstantiationException {
return c.newInstance();
}
@Override
public void newInstance(Object o) throws IllegalAccessException, InvocationTargetException, NamingException {
throw new IllegalStateException();
}
@Override
public void destroyInstance(Object o) throws IllegalAccessException, InvocationTargetException {
}
}
}