Java tutorial
/******************************************************************************* * Copyright (c) 2007 Cambridge Semantics Incorporated. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * File: $Source$ * Created by: Matthew Roy ( <a href="mailto:mroy@cambridgesemantics.com">mroy@cambridgesemantics.com </a>) * Created on: Nov 1, 2007 * Revision: $Id$ * * Contributors: * Cambridge Semantics Incorporated - initial API and implementation *******************************************************************************/ package org.openanzo.datasource.services; import java.io.IOException; import java.io.Writer; import java.util.LinkedHashSet; import java.util.Set; import java.util.TreeSet; import org.apache.commons.lang.ArrayUtils; import org.openanzo.analysis.RequestAnalysis; import org.openanzo.cache.ICacheProvider; import org.openanzo.datasource.IQueryService; import org.openanzo.exceptions.AnzoException; import org.openanzo.exceptions.ExceptionConstants; import org.openanzo.exceptions.LogUtils; import org.openanzo.exceptions.ExceptionConstants.IO; import org.openanzo.glitter.Engine; import org.openanzo.glitter.ParseOnlyEngineConfig; import org.openanzo.glitter.dataset.DefaultQueryDataset; import org.openanzo.glitter.dataset.QueryDataset; import org.openanzo.glitter.exception.GlitterParseException; import org.openanzo.glitter.exception.GlitterRuntimeException; import org.openanzo.glitter.query.PatternSolution; import org.openanzo.glitter.query.QueryController; import org.openanzo.glitter.query.SolutionSet; import org.openanzo.glitter.syntax.concrete.ParseException; import org.openanzo.rdf.Statement; import org.openanzo.rdf.URI; import org.openanzo.rdf.Constants.GRAPHS; import org.openanzo.rdf.Constants.OPTIONS; import org.openanzo.rdf.utils.SerializationConstants; import org.openanzo.rdf.utils.SerializationUtils; import org.openanzo.rdf.utils.UriGenerator; import org.openanzo.services.DynamicServiceStats; import org.openanzo.services.IOperationContext; import org.openanzo.services.IUpdateResultListener; import org.openanzo.services.Privilege; import org.openanzo.services.serialization.CommonSerializationUtils; import org.openanzo.services.serialization.IQueryResultsHandler; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Base implementation of the IQueryService * * @author Matthew Roy ( <a href="mailto:mroy@cambridgesemantics.com">mroy@cambridgesemantics.com </a>) * */ public abstract class BaseQueryService extends BaseDatasourceComponent implements IQueryService { private static final Logger log = LoggerFactory.getLogger(BaseQueryService.class); private final QueryServiceWithCacheStats stats = new QueryServiceWithCacheStats("query", "askQuery"); protected IQueryCache cache; protected void initCache(ICacheProvider cacheProvider) { if (cacheProvider != null) { createQueryCache(cacheProvider); } } protected void createQueryCache(ICacheProvider cacheProvider) { this.cache = new QueryCache(getDatasource().getInstanceURI().toString(), cacheProvider); } public String getName() { return getDatasource().getName() + ",Service=QueryService"; } public String getDescription() { return "Query Service for " + getDatasource().getName(); } public DynamicServiceStats getStatistics() { return stats; } public void start() throws AnzoException { stats.setEnabled(true); } public void reset() throws AnzoException { stats.reset(); if (cache != null) cache.reset(); } /** * Get the cacheUpdateListener for this service * * @return the cacheUpdateListener for this service */ public IUpdateResultListener getCacheUpdateListener() { return cache; } /** * Query where results are passed to handler * * @param context * @param defaultNamedGraphs * @param graphs * @param namedDatasets * @param paramQuery * @param queryString * @param baseUri * @param queryResultsHandler * @throws AnzoException */ public void query(IOperationContext context, Set<URI> defaultNamedGraphs, Set<URI> graphs, Set<URI> namedDatasets, String paramQuery, String queryString, URI baseUri, IQueryResultsHandler queryResultsHandler) throws AnzoException { // try { org.openanzo.glitter.query.QueryResults queryResults = query(context, defaultNamedGraphs, graphs, namedDatasets, paramQuery, queryString, baseUri); queryResultsHandler.start(queryResults.getQueryType(), queryResults.getTotalSolutions()); switch (queryResults.getQueryType()) { case ASK: queryResultsHandler.handleAskResult(queryResults.getAskResults()); break; case CONSTRUCT_QUADS: case DESCRIBE_QUADS: case CONSTRUCT: case DESCRIBE: for (Statement stmt : queryResults.getConstructResults()) { queryResultsHandler.handleStatement(stmt.getSubject(), stmt.getPredicate(), stmt.getObject(), stmt.getNamedGraphUri()); } break; case SELECT: SolutionSet solutionSet = queryResults.getSelectResults(); queryResultsHandler.handleBindings(solutionSet.getBindings()); for (PatternSolution sol : solutionSet) { queryResultsHandler.handleSolution(sol); } break; } queryResultsHandler.end(); } protected boolean canRead(IOperationContext context, URI namedGraphUri, boolean failIfNotFound) throws AnzoException { try { Set<URI> roles = getDatasource().getAuthorizationService().getRolesForGraph(context, namedGraphUri, Privilege.READ); if (!context.getOperationPrincipal().isSysadmin() && !org.openanzo.rdf.utils.Collections.memberOf(roles, context.getOperationPrincipal().getRoles())) { return false; } return true; } catch (AnzoException ae) { if (!failIfNotFound && ae.getErrorCode() == ExceptionConstants.DATASOURCE.NAMEDGRAPH.NOT_FOUND) { return false; } throw new GlitterRuntimeException(ae); } } protected QueryDataset resolveQueryUriSet(IOperationContext context, Set<URI> defaultGraphs, Set<URI> namedGraphs, Set<URI> namedDatasets) throws AnzoException { long start = System.currentTimeMillis(); DefaultQueryDataset uriSet = new DefaultQueryDataset(); if (defaultGraphs != null) { for (URI uri : defaultGraphs) { if (!uri.equals(GRAPHS.ALL_GRAPHS) && !uri.equals(GRAPHS.ALL_METADATAGRAPHS) && !uri.equals(GRAPHS.ALL_NAMEDGRAPHS)) { if (!canRead(context, uri, true)) { new GlitterRuntimeException(ExceptionConstants.DATASOURCE.NO_READ_ERROR, uri.toString()); } } else if (uri.equals(GRAPHS.ALL_GRAPHS)) { uriSet.defaultAllGraphs = true; } else if (uri.equals(GRAPHS.ALL_METADATAGRAPHS)) { uriSet.defaultAllMetadataGraphs = true; } else if (uri.equals(GRAPHS.ALL_NAMEDGRAPHS)) { uriSet.defaultAllNamedGraphs = true; } } } if (namedGraphs != null) { for (URI uri : namedGraphs) { if (!uri.equals(GRAPHS.ALL_GRAPHS) && !uri.equals(GRAPHS.ALL_METADATAGRAPHS) && !uri.equals(GRAPHS.ALL_NAMEDGRAPHS)) { if (!canRead(context, uri, true)) { new GlitterRuntimeException(ExceptionConstants.DATASOURCE.NO_READ_ERROR, uri.toString()); } } else if (uri.equals(GRAPHS.ALL_GRAPHS)) { uriSet.allGraphs = true; } else if (uri.equals(GRAPHS.ALL_METADATAGRAPHS)) { uriSet.allMetadataGraphs = true; } else if (uri.equals(GRAPHS.ALL_NAMEDGRAPHS)) { uriSet.allNamedGraphs = true; } } } boolean both = (((namedGraphs != null && namedGraphs.size() > 0) || uriSet.allGraphs || uriSet.allMetadataGraphs || uriSet.allNamedGraphs) || ((defaultGraphs != null && defaultGraphs.size() > 0) || uriSet.defaultAllGraphs || uriSet.defaultAllMetadataGraphs || uriSet.defaultAllNamedGraphs)) && (namedDatasets != null && namedDatasets.size() > 0); uriSet.setDefaultGraphs((both) ? new TreeSet<URI>() : new LinkedHashSet<URI>()); uriSet.setNamedGraphs((both) ? new TreeSet<URI>() : new LinkedHashSet<URI>()); // expand out the graph names from the named datasets if (defaultGraphs != null && defaultGraphs.size() > 0) { uriSet.getDefaultGraphURIs().addAll((both) ? defaultGraphs : new TreeSet<URI>(defaultGraphs)); } if (namedGraphs != null && namedGraphs.size() > 0) { uriSet.getNamedGraphURIs().addAll((both) ? namedGraphs : new TreeSet<URI>(namedGraphs)); } if (namedDatasets != null) { Boolean includeMetadata = context.getAttribute(OPTIONS.INCLUDEMETADATAGRAPHS, Boolean.class); boolean icm = includeMetadata != null ? includeMetadata : false; for (URI namedDataset : namedDatasets) { QueryDataset uris = getDatasource().getModelService().resolveNamedDataset(context, namedDataset); if (uris.fullyExpandedDatasets) { uriSet.getDefaultGraphURIs().addAll(uris.getDefaultGraphURIs()); uriSet.getNamedGraphURIs().addAll(uris.getNamedGraphURIs()); } else { if (uris.getDefaultGraphURIs() != null) { for (URI uri : uris.getDefaultGraphURIs()) { if (context.getOperationPrincipal().isSysadmin() || canRead(context, uri, false)) { uriSet.getDefaultGraphURIs().add(uri); if (icm && !UriGenerator.isMetadataGraphUri(uri) && (context.getOperationPrincipal().isSysadmin() || canRead(context, UriGenerator.generateMetadataGraphUri(uri), false))) { uriSet.getDefaultGraphURIs().add(UriGenerator.generateMetadataGraphUri(uri)); } } } } if (uris.getNamedGraphURIs() != null) { for (URI uri : uris.getNamedGraphURIs()) { if (context.getOperationPrincipal().isSysadmin() || canRead(context, uri, false)) { uriSet.getNamedGraphURIs().add(uri); if (icm && !UriGenerator.isMetadataGraphUri(uri) && (context.getOperationPrincipal().isSysadmin() || canRead(context, UriGenerator.generateMetadataGraphUri(uri), false))) { uriSet.getNamedGraphURIs().add(UriGenerator.generateMetadataGraphUri(uri)); } } } } } } } if (log.isDebugEnabled()) { log.debug(LogUtils.TIMING_MARKER, "RESOLVE QUERY URIS,{},{}", (System.currentTimeMillis() - start), uriSet.namedGraphs.size() + uriSet.defaultGraphs.size()); } return uriSet; } protected QueryDataset resolveAndVerifyGraphs(IOperationContext context, Set<URI> dngs, Set<URI> ngs, Set<URI> namedDatasets, String queryString, URI baseUri, QueryController prepareQuery) throws AnzoException { QueryDataset uriSet = null; if ((dngs == null || dngs.size() == 0) && (ngs == null || ngs.size() == 0) && (namedDatasets == null || namedDatasets.size() == 0)) { uriSet = resolveQueryUriSet(context, prepareQuery.getQueryDataset().getDefaultGraphURIs(), prepareQuery.getQueryDataset().getNamedGraphURIs(), prepareQuery.getQueryDataset().getNamedDatasetURIs()); } else { uriSet = resolveQueryUriSet(context, dngs, ngs, namedDatasets); } if (!(uriSet.allGraphs || uriSet.allMetadataGraphs || uriSet.allNamedGraphs || uriSet.defaultAllGraphs || uriSet.defaultAllMetadataGraphs || uriSet.defaultAllNamedGraphs)) { context.setAttribute("datasetResolved", Boolean.TRUE); uriSet.datasetFullyResolved = true; } return uriSet; } public org.openanzo.glitter.query.QueryResults query(IOperationContext context, Set<URI> defaultNamedGraphs, Set<URI> graphs, Set<URI> namedDatasets, String paramQuery, String queryString, URI baseUri) throws AnzoException { if (queryString == null || queryString.length() == 0) queryString = paramQuery; // TEMP fix until we drop support for // paramQuery in messages long start = 0; if (stats.isEnabled() || log.isDebugEnabled()) { start = System.currentTimeMillis(); } if (getLockProvider() != null) getLockProvider().readLock().lock(); logEntry(); if (log.isDebugEnabled()) { log.debug(LogUtils.DATASOURCE_MARKER, "Query:{} [{}] [{}] [{}]", new Object[] { queryString, defaultNamedGraphs != null ? ArrayUtils.toString(defaultNamedGraphs.toArray(new URI[0])) : "null", graphs != null ? ArrayUtils.toString(graphs.toArray(new URI[0])) : "null", namedDatasets != null ? ArrayUtils.toString(namedDatasets.toArray(new URI[0])) : "null" }); } try { QueryController prepareQuery = new Engine(new ParseOnlyEngineConfig()).prepareQuery(null, queryString, null, baseUri); QueryDataset uriSet = resolveAndVerifyGraphs(context, defaultNamedGraphs, graphs, namedDatasets, queryString, baseUri, prepareQuery); Boolean skipCache = context.getAttribute(OPTIONS.SKIPCACHE, Boolean.class); boolean skip = (skipCache != null && skipCache) || cache == null; skip |= (uriSet.allGraphs || uriSet.allMetadataGraphs || uriSet.allNamedGraphs || uriSet.defaultAllGraphs || uriSet.defaultAllMetadataGraphs || uriSet.defaultAllNamedGraphs); String cacheString = !skip ? queryString + uriSet.getCacheString() : null; org.openanzo.glitter.query.QueryResults queryResults = !skip ? cache.findResults(cacheString, uriSet) : null; if (queryResults == null) { if (stats.isEnabled()) { stats.getCacheMiss().increment(); } queryResults = executeQueryInternal(context, uriSet, queryString, baseUri); if (!skip && cache != null) { cache.cacheResults(cacheString, queryResults, uriSet); } if (RequestAnalysis.isAnalysisEnabled(context.getAttributes())) { RequestAnalysis.addAnalysisProperty(RequestAnalysis.ANS_PROP_CACHE_HIT, Boolean.FALSE); } } else { if (stats.isEnabled()) { stats.getCacheHit().increment(); } if (RequestAnalysis.isAnalysisEnabled(context.getAttributes())) { RequestAnalysis.addAnalysisProperty(RequestAnalysis.ANS_PROP_CACHE_HIT, Boolean.TRUE); } } if (log.isDebugEnabled()) { log.debug(LogUtils.TIMING_MARKER, "Total Query Time:results,{},{},{}", new Object[] { (System.currentTimeMillis() - start), queryResults.getTotalSolutions(), queryString }); } return queryResults; } catch (ParseException pe) { throw new GlitterParseException(pe, queryString, pe.getMessage()); } finally { if (stats.isEnabled()) { stats.use("query", (System.currentTimeMillis() - start)); } if (getLockProvider() != null) getLockProvider().readLock().unlock(); logExit(); } } public void askQuery(IOperationContext context, Set<URI> defaultNamedGraphs, Set<URI> graphs, Set<URI> namedDatasets, String paramQuery, String queryString, URI baseUri, boolean current, Writer out) throws AnzoException { boolean queryResults = askQuery(context, defaultNamedGraphs, graphs, namedDatasets, paramQuery, queryString, baseUri, current); SerializationUtils.writeValue(queryResults, out, null); } public boolean askQuery(IOperationContext context, Set<URI> defaultNamedGraphs, Set<URI> graphs, Set<URI> namedDatasets, String paramQuery, String queryString, URI baseUri, boolean current) throws AnzoException { if (queryString == null || queryString.length() == 0) queryString = paramQuery; // TEMP fix until we drop support for // paramQuery in messages long start = 0; if (stats.isEnabled()) { start = System.currentTimeMillis(); } if (getLockProvider() != null) getLockProvider().readLock().lock(); logEntry(); try { QueryController prepareQuery = new Engine(new ParseOnlyEngineConfig()).prepareQuery(null, queryString, null, baseUri); QueryDataset uriSet = resolveAndVerifyGraphs(context, defaultNamedGraphs, graphs, namedDatasets, queryString, baseUri, prepareQuery); Boolean skipCache = context.getAttribute(OPTIONS.SKIPCACHE, Boolean.class); boolean skip = (skipCache != null && skipCache) || cache == null; skip |= (uriSet.allGraphs || uriSet.allMetadataGraphs || uriSet.allNamedGraphs || uriSet.defaultAllGraphs || uriSet.defaultAllMetadataGraphs || uriSet.defaultAllNamedGraphs); String cacheString = !skip ? queryString + uriSet.getCacheString() : null; org.openanzo.glitter.query.QueryResults queryResults = !skip ? cache.findResults(cacheString, uriSet) : null; if (queryResults == null) { if (stats.isEnabled()) { stats.getCacheMiss().increment(); } queryResults = executeQueryInternal(context, uriSet, queryString, baseUri); if (!skip && cache != null) { cache.cacheResults(cacheString, queryResults, uriSet); } if (RequestAnalysis.isAnalysisEnabled(context.getAttributes())) { RequestAnalysis.addAnalysisProperty(RequestAnalysis.ANS_PROP_CACHE_HIT, Boolean.FALSE); } } else { if (stats.isEnabled()) { stats.getCacheHit().increment(); } if (RequestAnalysis.isAnalysisEnabled(context.getAttributes())) { RequestAnalysis.addAnalysisProperty(RequestAnalysis.ANS_PROP_CACHE_HIT, Boolean.TRUE); } } return queryResults.getAskResults(); } catch (ParseException pe) { throw new GlitterParseException(pe, queryString, pe.getMessage()); } finally { if (stats.isEnabled()) { stats.use("askQuery", (System.currentTimeMillis() - start)); } if (getLockProvider() != null) getLockProvider().readLock().unlock(); logExit(); } } /** * Run a query on the server's data * * @param context * {@link IOperationContext} context for this operation * * @param queryController * prepopulated QueryController * @return the results of the query * @throws AnzoException */ protected abstract org.openanzo.glitter.query.QueryResults executeQueryInternal(IOperationContext context, QueryDataset uriSet, String queryString, URI baseUri) throws AnzoException; public void query(IOperationContext context, Set<URI> defaultNamedGraphs, Set<URI> graphs, Set<URI> namedDatasets, String paramQuery, String queryString, URI baseUri, Writer out, String format) throws AnzoException { try { org.openanzo.glitter.query.QueryResults queryResults = query(context, defaultNamedGraphs, graphs, namedDatasets, paramQuery, queryString, baseUri); out.write(queryResults.getQueryType().name() + "\n"); CommonSerializationUtils.writeQueryResults(queryResults, out, format); context.setAttribute(SerializationConstants.totalSolutions, queryResults.getTotalSolutions()); } catch (IOException ioe) { throw new AnzoException(IO.WRITE_ERROR, ioe, ioe.getMessage()); } } }