| /******************************************************************************* |
| * Copyright (c) 2010, 2015 IBM Corporation and others. |
| * |
| * This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License 2.0 |
| * which accompanies this distribution, and is available at |
| * https://www.eclipse.org/legal/epl-2.0/ |
| * |
| * SPDX-License-Identifier: EPL-2.0 |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| |
| package org.eclipse.help.internal.criteria; |
| |
| import java.util.ArrayList; |
| import java.util.Iterator; |
| import java.util.List; |
| |
| import org.eclipse.core.runtime.CoreException; |
| import org.eclipse.core.runtime.IConfigurationElement; |
| import org.eclipse.core.runtime.IExtensionRegistry; |
| import org.eclipse.core.runtime.Platform; |
| import org.eclipse.help.AbstractCriteriaProvider; |
| import org.eclipse.help.ICriteria; |
| import org.eclipse.help.IToc; |
| import org.eclipse.help.IToc2; |
| import org.eclipse.help.ITopic; |
| import org.eclipse.help.ITopic2; |
| import org.eclipse.help.internal.HelpPlugin; |
| |
| public class CriteriaProviderRegistry { |
| |
| public static final String PROVIDER_XP_NAME = "org.eclipse.help.criteriaProvider"; //$NON-NLS-1$ |
| |
| private static List<AbstractCriteriaProvider> providers = null; |
| |
| private static CriteriaProviderRegistry instance; |
| |
| private boolean initialized = false; |
| |
| private CriteriaProviderRegistry() { |
| } |
| |
| public static CriteriaProviderRegistry getInstance() { |
| if (instance == null) { |
| instance = new CriteriaProviderRegistry(); |
| } |
| return instance; |
| } |
| |
| synchronized private void readProviders() { |
| if (initialized ) { |
| return; |
| } |
| providers = new ArrayList<>(); |
| IExtensionRegistry registry = Platform.getExtensionRegistry(); |
| IConfigurationElement[] elements = registry |
| .getConfigurationElementsFor(PROVIDER_XP_NAME); |
| for (int i = 0; i < elements.length; i++) { |
| |
| Object obj = null; |
| try { |
| obj = elements[i].createExecutableExtension("class"); //$NON-NLS-1$ |
| } catch (CoreException e) { |
| HelpPlugin.logError("Create extension failed:[" //$NON-NLS-1$ |
| + PROVIDER_XP_NAME + "].", e); //$NON-NLS-1$ |
| } |
| if (obj instanceof AbstractCriteriaProvider) { |
| providers.add((AbstractCriteriaProvider) obj); |
| } |
| } |
| initialized = true; |
| } |
| |
| public AbstractCriteriaProvider[] getScopes() { |
| readProviders(); |
| return providers.toArray(new AbstractCriteriaProvider[providers.size()]); |
| } |
| |
| public ICriteria[] getAllCriteria(ITopic topic) { |
| readProviders(); |
| ICriteria[] criteria; |
| if (topic instanceof ITopic2) { |
| criteria = ((ITopic2) topic).getCriteria(); |
| } else { |
| criteria = new ICriteria[0]; |
| } |
| for (Iterator<AbstractCriteriaProvider> iter = providers.iterator(); iter.hasNext();) { |
| AbstractCriteriaProvider provider = iter.next(); |
| ICriteria[] newCriteria = provider.getCriteria(topic); |
| if (newCriteria.length > 0) { |
| if (criteria.length == 0) { |
| criteria = newCriteria; |
| } else { |
| ICriteria[] union = new ICriteria[criteria.length + newCriteria.length]; |
| System.arraycopy(criteria, 0, union, 0, criteria.length); |
| System.arraycopy(newCriteria, 0, union, criteria.length, newCriteria.length); |
| criteria = union; |
| } |
| } |
| } |
| return criteria; |
| } |
| |
| public ICriteria[] getAllCriteria(IToc toc) { |
| readProviders(); |
| ICriteria[] criteria; |
| if (toc instanceof IToc2) { |
| criteria = ((IToc2) toc).getCriteria(); |
| } else { |
| criteria = new ICriteria[0]; |
| } |
| for (Iterator<AbstractCriteriaProvider> iter = providers.iterator(); iter.hasNext();) { |
| AbstractCriteriaProvider provider = iter.next(); |
| ICriteria[] newCriteria = provider.getCriteria(toc); |
| if (newCriteria.length > 0) { |
| if (criteria.length == 0) { |
| criteria = newCriteria; |
| } else { |
| ICriteria[] union = new ICriteria[criteria.length + newCriteria.length]; |
| System.arraycopy(criteria, 0, union, 0, criteria.length); |
| System.arraycopy(newCriteria, 0, union, criteria.length, newCriteria.length); |
| criteria = union; |
| } |
| } |
| } |
| return criteria; |
| } |
| |
| } |