Java tutorial
/******************************************************************************* * Copyright 2011 * Ubiquitous Knowledge Processing (UKP) Lab * Technische Universitt Darmstadt * * 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.dkpro.lab.engine.impl; import static org.dkpro.lab.storage.StorageService.CONTEXT_ID_SCHEME; import static org.dkpro.lab.storage.StorageService.LATEST_CONTEXT_SCHEME; import java.net.URI; import java.util.Map; import java.util.Map.Entry; import java.util.concurrent.ConcurrentHashMap; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.dkpro.lab.engine.LifeCycleManager; import org.dkpro.lab.engine.TaskContext; import org.dkpro.lab.engine.TaskContextFactory; import org.dkpro.lab.engine.TaskExecutionService; import org.dkpro.lab.logging.LoggingService; import org.dkpro.lab.storage.StorageService; import org.dkpro.lab.storage.UnresolvedImportException; import org.dkpro.lab.task.Task; import org.dkpro.lab.task.TaskContextMetadata; import org.safehaus.uuid.UUIDGenerator; import org.springframework.beans.factory.BeanNameAware; import org.springframework.beans.factory.annotation.Required; public class DefaultTaskContextFactory implements BeanNameAware, TaskContextFactory { private final Log log = LogFactory.getLog(getClass()); private final Map<String, TaskContext> contexts; private StorageService storageService; private LoggingService loggingService; private LifeCycleManager lifeCycleManager; private TaskExecutionService executionService; private String beanName; { contexts = new ConcurrentHashMap<String, TaskContext>(); } @Override public void destroyContext(TaskContext aExperimentContext) { unregisterContext(aExperimentContext); } @Override public TaskContext getContext(String aInstanceId) { if (contexts.containsKey(aInstanceId)) { return contexts.get(aInstanceId); } else if (getStorageService().containsContext(aInstanceId)) { TaskContextMetadata metadata = getStorageService().getContext(aInstanceId); TaskContext ctx = createContext(metadata); contexts.put(ctx.getId(), ctx); return ctx; } else { return null; } } @Override public TaskContext createContext(Task aConfiguration) { String shortName = aConfiguration.getType(); if (shortName.lastIndexOf('.') > -1) { shortName = shortName.substring(shortName.lastIndexOf('.') + 1); } TaskContextMetadata metadata = new TaskContextMetadata(); metadata.setId(shortName + "-" + nextId()); metadata.setType(aConfiguration.getType()); metadata.setImports(aConfiguration.getImports()); TaskContext ctx = createContext(metadata); resolveImports(ctx); registerContext(ctx); return ctx; } @Override public String getId() { return beanName; } public void registerContext(TaskContext aContext) { contexts.put(aContext.getId(), aContext); } public void unregisterContext(TaskContext aContext) { contexts.remove(aContext.getId()); } /** * This can be overwritten by subclasses to create different {@link TaskContext} * implementations. */ protected TaskContext createContext(TaskContextMetadata aMetadata) { DefaultTaskContext ctx = new DefaultTaskContext(this); ctx.setLifeCycleManager(getLifeCycleManager()); ctx.setStorageService(getStorageService()); ctx.setLoggingService(getLoggingService()); ctx.setExecutionService(getExecutionService()); ctx.setMetadata(aMetadata); return ctx; } protected void resolveImports(TaskContext aContext) { for (Entry<String, String> e : aContext.getMetadata().getImports().entrySet()) { URI uri = URI.create(e.getValue()); // Try resolving by type if (LATEST_CONTEXT_SCHEME.equals(uri.getScheme()) || CONTEXT_ID_SCHEME.equals(uri.getScheme())) { String uuid; uuid = aContext.resolve(uri).getId(); if (!getStorageService().containsKey(uuid, uri.getPath())) { throw new UnresolvedImportException(aContext, e.getKey(), e.getValue(), "Key not found"); } String resolvedUri = CONTEXT_ID_SCHEME + "://" + uuid + uri.getPath(); log.debug("Resolved import [" + e.getValue() + "] -> [" + resolvedUri + "]"); e.setValue(resolvedUri); } } } protected String nextId() { return UUIDGenerator.getInstance().generateTimeBasedUUID().toString(); } @Override public void setBeanName(String aName) { try { if (beanName != null) { StaticContext.unbind(beanName); } beanName = aName; if (beanName != null) { StaticContext.bind(beanName, this); } } catch (Exception e) { throw new IllegalStateException(e); } } @Required public void setLifeCycleManager(LifeCycleManager aLifeCycleManager) { lifeCycleManager = aLifeCycleManager; } public LifeCycleManager getLifeCycleManager() { return lifeCycleManager; } @Required public void setStorageService(StorageService aStorageService) { storageService = aStorageService; } public StorageService getStorageService() { return storageService; } @Required public void setLoggingService(LoggingService aLoggingService) { loggingService = aLoggingService; } public LoggingService getLoggingService() { return loggingService; } @Required public void setExecutionService(TaskExecutionService aExecutionService) { executionService = aExecutionService; } public TaskExecutionService getExecutionService() { return executionService; } }