001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.camel.blueprint;
018    
019    import org.apache.camel.TypeConverter;
020    import org.apache.camel.core.osgi.OsgiCamelContextHelper;
021    import org.apache.camel.core.osgi.OsgiFactoryFinderResolver;
022    import org.apache.camel.core.osgi.OsgiTypeConverter;
023    import org.apache.camel.core.osgi.utils.BundleContextUtils;
024    import org.apache.camel.core.osgi.utils.BundleDelegatingClassLoader;
025    import org.apache.camel.impl.DefaultCamelContext;
026    import org.apache.camel.spi.FactoryFinder;
027    import org.apache.camel.spi.Registry;
028    import org.osgi.framework.BundleContext;
029    import org.osgi.framework.ServiceEvent;
030    import org.osgi.framework.ServiceListener;
031    import org.osgi.service.blueprint.container.BlueprintContainer;
032    import org.slf4j.Logger;
033    import org.slf4j.LoggerFactory;
034    
035    public class BlueprintCamelContext extends DefaultCamelContext implements ServiceListener {
036    
037        private static final transient Logger LOG = LoggerFactory.getLogger(BlueprintCamelContext.class);
038    
039        private BundleContext bundleContext;
040        private BlueprintContainer blueprintContainer;
041    
042        public BlueprintCamelContext() {
043        }
044    
045        public BlueprintCamelContext(BundleContext bundleContext, BlueprintContainer blueprintContainer) {
046            this.bundleContext = bundleContext;
047            this.blueprintContainer = blueprintContainer;
048    
049            // inject common osgi
050            OsgiCamelContextHelper.osgiUpdate(this, bundleContext);
051    
052            // and these are blueprint specific
053            setComponentResolver(new BlueprintComponentResolver(bundleContext));
054            setLanguageResolver(new BlueprintLanguageResolver(bundleContext));
055            setDataFormatResolver(new BlueprintDataFormatResolver(bundleContext));
056            setApplicationContextClassLoader(new BundleDelegatingClassLoader(bundleContext.getBundle()));
057        }
058    
059        public BundleContext getBundleContext() {
060            return bundleContext;
061        }
062    
063        public void setBundleContext(BundleContext bundleContext) {
064            this.bundleContext = bundleContext;
065        }
066    
067        public BlueprintContainer getBlueprintContainer() {
068            return blueprintContainer;
069        }
070    
071        public void setBlueprintContainer(BlueprintContainer blueprintContainer) {
072            this.blueprintContainer = blueprintContainer;
073        }
074    
075        public void init() throws Exception {
076            // add service listener so we can be notified when blueprint container is done
077            // and we would be ready to start CamelContext
078            bundleContext.addServiceListener(this);
079        }
080    
081        public void destroy() throws Exception {
082            // remove listener and stop this CamelContext
083            bundleContext.removeServiceListener(this);
084            stop();
085        }
086    
087        @Override
088        public void serviceChanged(ServiceEvent event) {
089            if (LOG.isDebugEnabled()) {
090                LOG.debug("Service {} changed to {}", event, event.getType());
091            }
092            // look for blueprint container to be registered, and then we can start the CamelContext
093            if (event.getType() == ServiceEvent.REGISTERED && event.getServiceReference().isAssignableTo(bundleContext.getBundle(),
094                    "org.osgi.service.blueprint.container.BlueprintContainer")) {
095                try {
096                    maybeStart();
097                } catch (Exception e) {
098                    LOG.warn("Error occurred during starting " + this, e);
099                }
100            }
101        }
102    
103        @Override
104        protected TypeConverter createTypeConverter() {
105            // CAMEL-3614: make sure we use a bundle context which imports org.apache.camel.impl.converter package
106            BundleContext ctx = BundleContextUtils.getBundleContext(getClass());
107            if (ctx == null) {
108                ctx = bundleContext;
109            }
110            FactoryFinder finder = new OsgiFactoryFinderResolver(bundleContext).resolveDefaultFactoryFinder(getClassResolver());
111            return new OsgiTypeConverter(ctx, getInjector(), finder);
112        }
113    
114        @Override
115        protected Registry createRegistry() {
116            Registry reg = new BlueprintContainerRegistry(getBlueprintContainer());
117            return OsgiCamelContextHelper.wrapRegistry(this, reg, bundleContext);
118        }
119    
120        private void maybeStart() throws Exception {
121            if (!isStarted() && !isStarting()) {
122                final ClassLoader original = Thread.currentThread().getContextClassLoader();
123                try {
124                    // let's set a more suitable TCCL while starting the context
125                    Thread.currentThread().setContextClassLoader(getApplicationContextClassLoader());
126                    LOG.debug("Starting {}", this);
127                    start();
128                } finally {
129                    Thread.currentThread().setContextClassLoader(original);
130                }
131            } else {
132                // ignore as Camel is already started
133                LOG.trace("Ignoring maybeStart() as {} is already started", this);
134            }
135        }
136    }