org.apache.ignite.osgi.IgniteAbstractOsgiContextActivator Maven / Gradle / Ivy
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/*
* 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.ignite.osgi;
import java.util.Dictionary;
import java.util.Hashtable;
import org.apache.ignite.Ignite;
import org.apache.ignite.IgniteException;
import org.apache.ignite.IgniteLogger;
import org.apache.ignite.Ignition;
import org.apache.ignite.configuration.IgniteConfiguration;
import org.apache.ignite.internal.util.typedef.internal.A;
import org.apache.ignite.internal.util.typedef.internal.U;
import org.apache.ignite.osgi.classloaders.BundleDelegatingClassLoader;
import org.apache.ignite.osgi.classloaders.ContainerSweepClassLoader;
import org.apache.ignite.osgi.classloaders.OsgiClassLoadingStrategyType;
import org.jetbrains.annotations.Nullable;
import org.osgi.framework.BundleActivator;
import org.osgi.framework.BundleContext;
/**
* This {@link BundleActivator} starts Apache Ignite inside the OSGi container when the bundle is started.
*
* Create an implementation of this class and set the {@code Bundle-Activator} OSGi Manifest header to the FQN of
* your class.
*
* You must provide the {@link IgniteConfiguration} to start by implementing the {@link #igniteConfiguration()}
* abstract method. The return value of this method cannot be {@code null}. For example, if your implementation is
* called {@code org.myorg.osgi.IgniteActivator}, your bundle must provide the following header:
*
* Bundle-Activator: org.myorg.osgi.IgniteActivator
*
* You may use the
* Maven
* Bundle Plugin to generate your bundle (or bundle manifest), including the required header.
*
* This activator also exports the Ignite instance as an OSGi service, with the property {@code ignite.name} set
* to the value of {@link Ignite#name()}, if and only if the name is not null.
*
* Currently, Ignite only allows a single instance per container. We may remove this limitation if enough demand
* builds up in the community.
*
* @see Bundle-Activator OSGi Manifest header
*
*/
public abstract class IgniteAbstractOsgiContextActivator implements BundleActivator {
/** OSGI service property name. */
public static final String OSGI_SERVICE_PROP_IGNITE_NAME = "ignite.name";
/** The instance of Ignite started by this Activator. */
protected Ignite ignite;
/** Our bundle context. */
private BundleContext bundleCtx;
/** Ignite logger. */
private IgniteLogger log;
/**
* Method invoked by OSGi to start the bundle. It starts the specified Ignite configuration.
*
* @param ctx Bundle context.
* @throws Exception
*/
@Override public final void start(BundleContext ctx) throws Exception {
// Ensure that no other instances are running.
if (IgniteOsgiUtils.gridCount() > 0) {
throw new IgniteException("Failed to start Ignite instance (another instance is already running " +
"and ignite-osgi is currently limited to a single instance per container).");
}
bundleCtx = ctx;
// Start the Ignite configuration specified by the user.
IgniteConfiguration cfg = igniteConfiguration();
A.notNull(cfg, "Ignite configuration");
// Override the classloader with the classloading strategy chosen by the user.
ClassLoader clsLdr;
if (classLoadingStrategy() == OsgiClassLoadingStrategyType.BUNDLE_DELEGATING)
clsLdr = new BundleDelegatingClassLoader(bundleCtx.getBundle(), Ignite.class.getClassLoader());
else
clsLdr = new ContainerSweepClassLoader(bundleCtx.getBundle(), Ignite.class.getClassLoader());
cfg.setClassLoader(clsLdr);
onBeforeStart(ctx);
// Start Ignite.
try {
ignite = Ignition.start(cfg);
}
catch (Throwable t) {
U.error(log, "Failed to start Ignite via OSGi Activator [errMsg=" + t.getMessage() + ']', t);
onAfterStart(ctx, t);
return;
}
log = ignite.log();
log.info("Started Ignite from OSGi Activator [name=" + ignite.name() + ']');
// Add into Ignite's OSGi registry.
IgniteOsgiUtils.classloaders().put(ignite, clsLdr);
// Export Ignite as a service.
exportOsgiService(ignite);
onAfterStart(ctx, null);
}
/**
* Stops Ignite when the bundle is stopping.
*
* @param ctx Bundle context.
* @throws Exception If failed.
*/
@Override public final void stop(BundleContext ctx) throws Exception {
onBeforeStop(ctx);
try {
ignite.close();
}
catch (Throwable t) {
U.error(log, "Failed to stop Ignite via OSGi Activator [errMsg=" + t.getMessage() + ']', t);
onAfterStop(ctx, t);
return;
}
if (log.isInfoEnabled())
log.info("Stopped Ignite from OSGi Activator [name=" + ignite.name() + ']');
IgniteOsgiUtils.classloaders().remove(ignite);
onAfterStop(ctx, null);
}
/**
* This method is called before Ignite initialises.
*
* The default implementation is empty. Override it to introduce custom logic.
*
* @param ctx The {@link BundleContext}.
*/
protected void onBeforeStart(BundleContext ctx) {
// No-op.
}
/**
* This method is called after Ignite initialises, only if initialization succeeded.
*
* The default implementation is empty. Override it to introduce custom logic.
*
* @param ctx The {@link BundleContext}.
* @param t Throwable in case an error occurred when starting. {@code null} otherwise.
*/
protected void onAfterStart(BundleContext ctx, @Nullable Throwable t) {
// No-op.
}
/**
* This method is called before Ignite stops.
*
* The default implementation is empty. Override it to introduce custom logic.
*
* @param ctx The {@link BundleContext}.
*/
protected void onBeforeStop(BundleContext ctx) {
// No-op.
}
/**
* This method is called after Ignite stops, only if the operation succeeded.
*
* The default implementation is empty. Override it to introduce custom logic.
*
* @param ctx The {@link BundleContext}.
* @param t Throwable in case an error occurred when stopping. {@code null} otherwise.
*/
protected void onAfterStop(BundleContext ctx, @Nullable Throwable t) {
// No-op.
}
/**
* Override this method to provide the Ignite configuration this bundle will start.
*
* @return The Ignite configuration.
*/
public abstract IgniteConfiguration igniteConfiguration();
/**
* Override this method to indicate which classloading strategy to use.
*
* @return The strategy.
*/
public OsgiClassLoadingStrategyType classLoadingStrategy() {
return OsgiClassLoadingStrategyType.BUNDLE_DELEGATING;
}
/**
* Exports the Ignite instance onto the OSGi Service Registry.
*
* @param ignite Ignite.
*/
private void exportOsgiService(Ignite ignite) {
Dictionary dict = new Hashtable<>();
// Only add the service property if the grid name != null.
if (ignite.name() != null)
dict.put(OSGI_SERVICE_PROP_IGNITE_NAME, ignite.name());
bundleCtx.registerService(Ignite.class, ignite, dict);
if (log.isInfoEnabled())
log.info("Exported OSGi service for Ignite with properties: " + dict);
}
}