diff options
Diffstat (limited to 'sca-java-1.x/tags/java-M1-final/java/sca/core/src/main/java/org/apache/tuscany/core/context/scope/ModuleScopeContext.java')
| -rw-r--r-- | sca-java-1.x/tags/java-M1-final/java/sca/core/src/main/java/org/apache/tuscany/core/context/scope/ModuleScopeContext.java | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/sca-java-1.x/tags/java-M1-final/java/sca/core/src/main/java/org/apache/tuscany/core/context/scope/ModuleScopeContext.java b/sca-java-1.x/tags/java-M1-final/java/sca/core/src/main/java/org/apache/tuscany/core/context/scope/ModuleScopeContext.java new file mode 100644 index 0000000000..dbb342bb5a --- /dev/null +++ b/sca-java-1.x/tags/java-M1-final/java/sca/core/src/main/java/org/apache/tuscany/core/context/scope/ModuleScopeContext.java @@ -0,0 +1,194 @@ +/** + * + * Copyright 2005 The Apache Software Foundation or its licensors, as applicable. + * + * Licensed 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.tuscany.core.context.scope; + +import org.apache.tuscany.core.builder.ContextFactory; +import org.apache.tuscany.core.context.AtomicContext; +import org.apache.tuscany.core.context.Context; +import org.apache.tuscany.core.context.CoreRuntimeException; +import org.apache.tuscany.core.context.EventContext; +import org.apache.tuscany.core.context.TargetException; +import org.apache.tuscany.core.context.Lifecycle; +import org.apache.tuscany.core.context.event.InstanceCreated; +import org.apache.tuscany.core.context.event.Event; +import org.apache.tuscany.core.context.event.ModuleStart; +import org.apache.tuscany.core.context.event.ModuleStop; + +import java.util.Map; +import java.util.List; +import java.util.ArrayList; +import java.util.ListIterator; +import java.util.concurrent.ConcurrentHashMap; + +/** + * Manages contexts whose implementations are module scoped. This scope contexts eagerly starts contexts when + * a {@link ModuleStart} event is received. If a contained context has an implementation marked to eagerly initialized, + * the an instance will be created at that time as well. Contained contexts are shutdown when a {@link ModuleStop} + * event is received in reverse order to which their implementation instances were created. + * + * @version $Rev$ $Date$ + */ +public class ModuleScopeContext extends AbstractScopeContext { + + // Component contexts in this scope keyed by name + private Map<String, Context> contexts; + + // the queue of contexts to destroy, in the order that their instances were created + private List<Context> destroyQueue; + + public ModuleScopeContext(EventContext eventContext) { + super(eventContext); + setName("Module Scope"); + } + + public void onEvent(Event event) { + if (event instanceof ModuleStart) { + lifecycleState = RUNNING; + initComponentContexts(); + } else if (event instanceof ModuleStop) { + shutdownContexts(); + } else if (event instanceof InstanceCreated) { + checkInit(); + if (event.getSource() instanceof Context) { + Context context = (Context) event.getSource(); + // Queue the context to have its implementation instance released if destroyable + destroyQueue.add(context); + } + } + } + + public synchronized void start() { + if (lifecycleState != UNINITIALIZED) { + throw new IllegalStateException("Scope must be in UNINITIALIZED state [" + lifecycleState + "]"); + } + } + + public synchronized void stop() { + if (lifecycleState != RUNNING) { + throw new IllegalStateException("Scope in wrong state [" + lifecycleState + "]"); + } + contexts = null; + destroyQueue = null; + lifecycleState = STOPPED; + } + + public boolean isCacheable() { + return true; + } + + public void registerFactory(ContextFactory<Context> configuration) { + contextFactories.put(configuration.getName(), configuration); + if (lifecycleState == RUNNING) { + contexts.put(configuration.getName(), configuration.createContext()); + } + } + + public Context getContext(String ctxName) { + checkInit(); + initComponentContexts(); + return contexts.get(ctxName); + } + + public Context getContextByKey(String ctxName, Object key) { + checkInit(); + initComponentContexts(); + return contexts.get(ctxName); + } + + public void removeContext(String ctxName) { + checkInit(); + if (contexts == null){ + return; + } + Context context = contexts.remove(ctxName); + if (context != null) { + destroyQueue.remove(context); + } + } + + public void removeContextByKey(String ctxName, Object key){ + removeContext(ctxName); + } + + /** + * Notifies contexts of a shutdown in reverse order to which they were started + */ + private synchronized void shutdownContexts() { + if (destroyQueue == null || destroyQueue.size() == 0) { + return; + } + // shutdown destroyable instances in reverse instantiation order + ListIterator<Context> iter = destroyQueue.listIterator(destroyQueue.size()); + while(iter.hasPrevious()){ + Lifecycle context = iter.previous(); + if (context.getLifecycleState() == RUNNING) { + try { + if (context instanceof AtomicContext){ + ((AtomicContext)context).destroy(); + } + } catch (TargetException e) { + // TODO send a monitoring event + } + } + } + if (contexts == null){ + return; + } + for(Lifecycle context: contexts.values()) { + try { + if (context.getLifecycleState() == RUNNING) { + context.stop(); + } + } catch (CoreRuntimeException e){ + // TODO send monitoring event + } + } + contexts = null; + destroyQueue = null; + } + + /** + * Creates and starts components contexts in the module scope. Implementations marked to eagerly initialize will + * also be notified to do so. + * + * @throws CoreRuntimeException + */ + private synchronized void initComponentContexts() throws CoreRuntimeException { + if (contexts == null) { + contexts = new ConcurrentHashMap<String, Context>(); + destroyQueue = new ArrayList<Context>(); + for (ContextFactory<Context> config : contextFactories.values()) { + Context context = config.createContext(); + context.start(); + contexts.put(context.getName(), context); + } + // Initialize eager contexts. Note this cannot be done when we initially create each context since a component may + // contain a forward reference to a component which has not been instantiated + for (Context context : contexts.values()) { + if (context instanceof AtomicContext) { + AtomicContext atomic = (AtomicContext) context; + if (atomic.isEagerInit()) { + // perform silent creation and manual shutdown registration + atomic.init(); + destroyQueue.add(context); + } + } + context.addListener(this); + } + } + } +}
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