matthiasblaesing commented on a change in pull request #3209: URL: https://github.com/apache/netbeans/pull/3209#discussion_r734984047
########## File path: ide/parsing.indexing/src/org/netbeans/modules/parsing/impl/indexing/IndexabilityQuery.java ########## @@ -0,0 +1,160 @@ +/* + * 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.netbeans.modules.parsing.impl.indexing; + +import java.net.URL; +import java.util.ArrayList; +import java.util.HashSet; +import java.util.List; +import java.util.Set; +import javax.swing.event.ChangeEvent; +import javax.swing.event.ChangeListener; +import org.netbeans.modules.parsing.spi.indexing.IndexabilityQueryImplementation; +import org.openide.filesystems.FileObject; +import org.openide.util.Exceptions; +import org.openide.util.Lookup; +import org.openide.util.LookupEvent; +import org.openide.util.LookupListener; + +/** + * Determine whether files should be skipped by the netbeans indexing infrastructure. + * + * @see org.netbeans.modules.parsing.spi.indexing.IndexabilityQueryImplementation + */ +public final class IndexabilityQuery { + private static final IndexabilityQuery INSTANCE = new IndexabilityQuery(); + + private final ResultListener resultListener = new ResultListener(); + private final IqiChangedListener vqiListener = new IqiChangedListener(); + + private final List<ChangeListener> listeners = new ArrayList<>(); + private volatile List<IndexabilityQueryImplementation> cachedIqiInstances = null; + private Lookup.Result<IndexabilityQueryImplementation> iqiResult = null; + + /** + * Get default instance of IndexabilityQuery. + * @return instance of IndexabilityQuery + */ + public static final IndexabilityQuery getDefault() { + return INSTANCE; + } + + private IndexabilityQuery() { + } + + boolean preventIndexing(FileObject fileObject) { + for (IndexabilityQueryImplementation iqi : getIqiInstances()) { + if (iqi.preventIndexing(fileObject)) { + return true; + } + } + return false; + } + + boolean preventIndexing (String indexerName, String factoryClassName, URL indexable, URL rootUrl) { + for (IndexabilityQueryImplementation iqi : getIqiInstances()) { + if (iqi.preventIndexing(indexerName, factoryClassName, indexable, rootUrl)) { + return true; + } + } + return false; + } + + /** + * Add a listener to changes. + * @param l a listener to add + */ + public void addChangeListener(ChangeListener l) { + synchronized (listeners) { + listeners.add(l); + } + } + + /** + * Stop listening to changes. + * @param l a listener to remove + */ + public void removeChangeListener(ChangeListener l) { + synchronized (listeners) { + listeners.remove(l); + } + } + + private void fireChange(ChangeEvent event) { + assert event != null; + ArrayList<ChangeListener> lists; + synchronized (listeners) { + lists = new ArrayList<>(listeners); + } + for (ChangeListener listener : lists) { + try { + listener.stateChanged(event); + } catch (RuntimeException x) { + Exceptions.printStackTrace(x); + } + } + } + + @SuppressWarnings("ReturnOfCollectionOrArrayField") + private synchronized List<IndexabilityQueryImplementation> getIqiInstances() { + if (cachedIqiInstances == null) { + iqiResult = Lookup.getDefault().lookupResult(IndexabilityQueryImplementation.class); + iqiResult.addLookupListener(resultListener); + setupChangeListeners(null, new ArrayList<>(iqiResult.allInstances())); Review comment: This code path is taken exactly once - all further updates are issued by the result listener. I think this is ok. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected] For further information about the NetBeans mailing lists, visit: https://cwiki.apache.org/confluence/display/NETBEANS/Mailing+lists
