/*******************************************************************************
* Copyright (c) 2008-2010 Martin Lippert and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Martin Lippert initial implementation
*******************************************************************************/
package org.eclipse.springframework.util;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IExecutableExtension;
import org.eclipse.core.runtime.IExecutableExtensionFactory;
import org.eclipse.core.runtime.IExtension;
import org.eclipse.core.runtime.Platform;
import org.osgi.framework.Bundle;
import org.osgi.framework.BundleException;
import org.springframework.context.ApplicationContext;
/**
* The Spring Extension Factory builds a bridge between the Eclipse Extension
* Registry and the Spring Framework (especially Spring Dynamic Modules).
*
* It allows you to define your extension as a spring bean within the spring
* application context of your bundle. If you would like to use this bean as an
* instance of an extension (an Eclipse RCP view, for example) you define the
* extension with this spring extension factory as the class to be created.
*
* To let the spring extension factory pick the right bean from your application
* context you need to set the bean id to the same value as the id of the view
* within the view definition, for example. This is important if your extension
* definition contains more than one element, where each element has its own id.
*
* If the extension definition elements themselves have no id attribute the
* spring extension factory uses the id of the extension itself to identify the
* bean.
*
* The Spring extension factory waits for the application context to be created
* using a timeout. Its default setting is five seconds. If you have a situation
* where you need a longer timeout because the spring context creation takes
* more time you can set the property
*
* org.eclipse.springextensionfactory.timeout
*
* to the milliseconds you would like to use as timeout.
*
* @author Martin Lippert
*/
public class SpringExtensionFactory implements IExecutableExtensionFactory,
IExecutableExtension {
private static final String TIMEOUT_PROPERTY_NAME = "org.eclipse.springextensionfactory.timeout";
private Object bean;
public Object create() throws CoreException {
return bean;
}
public void setInitializationData(IConfigurationElement config,
String propertyName, Object data) throws CoreException {
String beanName = getBeanName(data, config);
ApplicationContext appContext = getApplicationContext(config);
if (appContext == null) {
throw new RuntimeException("application context for bundle " + config.getContributor().getName() + " not found");
}
if (beanName == null) {
throw new RuntimeException("bean id cound not be identified. Please check your extension declaration");
}
this.bean = appContext.getBean(beanName);
if (this.bean instanceof IExecutableExtension) {
((IExecutableExtension) this.bean).setInitializationData(
config, propertyName, data);
}
}
private String getBeanName(Object data, IConfigurationElement config) {
// try the specific bean id the extension defines
if (data != null && data.toString().length() > 0) {
return data.toString();
}
// try the id of the config element
if (config.getAttribute("id") != null) {
return config.getAttribute("id");
}
// try the id of the extension element itself
if (config.getParent() != null
&& config.getParent() instanceof IExtension) {
IExtension extensionDefinition = (IExtension) config.getParent();
return extensionDefinition.getSimpleIdentifier();
}
return null;
}
private ApplicationContext getApplicationContext(
IConfigurationElement config) {
int timeout = 5000;
try {
String timeoutSetting = System.getProperty(TIMEOUT_PROPERTY_NAME);
timeout = Integer.parseInt(timeoutSetting);
}
catch (Exception e) {
}
String contributorName = config.getContributor().getName();
Bundle contributorBundle = Platform.getBundle(contributorName);
if (contributorBundle.getState() != Bundle.ACTIVE) {
try {
contributorBundle.start();
} catch (BundleException e) {
e.printStackTrace();
}
}
final ApplicationContextTracker applicationContextTracker = new ApplicationContextTracker(
contributorBundle, Activator.getDefault().getBundleContext());
ApplicationContext applicationContext = null;
try {
applicationContext = applicationContextTracker
.getApplicationContext(timeout);
} finally {
applicationContextTracker.close();
}
return applicationContext;
}
}