org.apache.tomee.loader.TomcatHook Maven / Gradle / Ivy
/**
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.tomee.loader;
import org.apache.openejb.loader.Embedder;
import org.apache.openejb.loader.IO;
import org.apache.openejb.loader.ProvisioningUtil;
import org.apache.openejb.loader.SystemInstance;
import java.io.File;
import java.lang.reflect.Method;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.Properties;
/**
* This class should only be loadded and used via reflection from TomcatEmbedder.
*
* Everything that happens up to the point of calling this particular method
* (except setting tomee.war) ultimately means nothing and does not matter
* to the integration.
*
* Requires tomee.war to be set, the sets the following properties:
*
* System properties:
* set openejb.home -> catalina.home
* set openejb.base -> catalina.base
* set tomee.war -> $tomee.war
* set tomcat.version if not set
* set tomcat.built if not set
*
* Local properties:
* set openejb.loader -> tomcat-system
* set openejb.libs -> $tomee.war/lib
*
* With these properties setup, this class with construct an {@link Embedder}
* using the "org.apache.tomee.catalina.TomcatLoader" as the loader.
*
* The Embedder will use the openejb.libs property to find all the jars to be loaded
* then it will use the openejb.loader property to find out *how* to add them into
* the classpath of the right classloader. Once all the jars are in the required
* class loader, it loads the {@link org.apache.openejb.loader.Loader} implementation
* and calls it's {@link org.apache.openejb.loader.Loader#init} method.
*
* See org.apache.tomee.catalina.TomcatLoader for the next part of the story
*/
class TomcatHook {
/**
* Using tomee.war path, it sets several required
* system properties and init {@link SystemInstance#init(Properties)}
*
*
* This method is called from {@link TomcatEmbedder#embed(Properties, ClassLoader)}
* method from classloader that contains openejb-loader and tomee-loader
* with CatalinaClassLoader as the parent.
*
* @param properties properties file
*/
static void hook(final Properties properties) {
// verify properties and make sure it contains the tomee.war property
if (properties == null) {
throw new NullPointerException("properties is null");
}
//Check tomee.war property
//This property is set by the LoaderServlet or OpenEJBListener
//When you deploy tomee.war into webapps/ directory of the tomcat
//Loader servlet automatically starts and initialize this property
if (!properties.containsKey("tomee.war")) {
throw new IllegalArgumentException("properties must contain the tomee.war property");
}
//Get the openejb directory (under webapps) using the tomee.war property
final File openejbWar = new File(properties.getProperty("tomee.war"));
if (!openejbWar.isDirectory()) {
throw new IllegalArgumentException("tomee.war is not a directory: " + openejbWar);
}
// if SystemInstance is already initialized, then return
if (SystemInstance.isInitialized()) {
return;
}
// set the openejb.loader property to tomcat-system
properties.setProperty("openejb.loader", "tomcat-system");
// Get the value of catalina.home and set it to openejb.home
final String catalinaHome = System.getProperty("catalina.home");
properties.setProperty("openejb.home", catalinaHome);
//Sets system property for openejb.home
System.setProperty("openejb.home", catalinaHome);
//get the value of catalina.base and set it to openejb.base
final String catalinaBase = System.getProperty("catalina.base");
properties.setProperty("openejb.base", catalinaBase);
//Sets system property for openejb.base
System.setProperty("openejb.base", catalinaBase);
// Set the tomee.war property as a *System* property
System.setProperty("tomee.war", openejbWar.getAbsolutePath());
// set the property openejb.libs to contain the absolute path of the lib directory of openejb webapp
final File libDir = new File(openejbWar, "lib");
final String libPath = libDir.getAbsolutePath();
//Sets openejb.libs to tomee.war/lib folder
properties.setProperty("openejb.libs", libPath);
// System.setProperty("tomcat.version", "x.y.z.w");
// System.setProperty("tomcat.built", "mmm dd yyyy hh:mm:ss");
// set the System properties, tomcat.version, tomcat.built
final ClassLoader classLoader = TomcatHook.class.getClassLoader();
try {
final Properties tomcatServerInfo = IO.readProperties(classLoader.getResourceAsStream("org/apache/catalina/util/ServerInfo.properties"), new Properties());
String serverNumber = tomcatServerInfo.getProperty("server.number");
if (serverNumber == null) {
// Tomcat5 only has server.info
final String serverInfo = tomcatServerInfo.getProperty("server.info");
if (serverInfo != null) {
final int slash = serverInfo.indexOf('/');
serverNumber = serverInfo.substring(slash + 1);
}
}
if (serverNumber != null) {
System.setProperty("tomcat.version", serverNumber);
}
final String serverBuilt = tomcatServerInfo.getProperty("server.built");
if (serverBuilt != null) {
System.setProperty("tomcat.built", serverBuilt);
}
} catch (final Throwable e) {
// no-op
}
if( properties.getProperty("openejb.libs") == null){
throw new NullPointerException("openejb.libs property is not set");
}
// manage additional libraries
if (URLClassLoader.class.isInstance(classLoader)) {
final URLClassLoader ucl = URLClassLoader.class.cast(classLoader);
try {
final Method addUrl = URLClassLoader.class.getDeclaredMethod("addURL", URL.class);
for (final File f : ProvisioningUtil.addAdditionalLibraries()) {
if (!addUrl.isAccessible()) { // set it lazily
addUrl.setAccessible(true);
}
addUrl.invoke(ucl, f.toURI().toURL());
}
} catch (final Exception e) {
e.printStackTrace(); // shouldn't block
}
}
// set the embedder
final Embedder embedder = new Embedder("org.apache.tomee.catalina.TomcatLoader");
SystemInstance.get().setComponent(Embedder.class, embedder);
try {
// create the loader
// This init call affects only this WebappClassloader and is just required
// for runnig the Embedder. The SystemInstance will be initialized more permanently
// in the parent classloader once the required libraries are added.
SystemInstance.init(properties);
// This guy does the magic of squishing the openejb libraries into the parent classloader
// and kicking off the reall integration.
embedder.init(properties);
} catch (final Exception e) {
e.printStackTrace();
}
}
}