Java tutorial
/* * 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.apache.solr.handler.component; import java.io.IOException; import java.util.Collections; import java.util.List; import java.util.Map; import java.util.function.Function; import java.util.stream.Stream; import com.google.common.base.MoreObjects; import org.apache.lucene.search.Query; import org.apache.solr.common.SolrException; import org.apache.solr.common.params.HighlightParams; import org.apache.solr.common.params.SolrParams; import org.apache.solr.common.util.NamedList; import org.apache.solr.common.util.SimpleOrderedMap; import org.apache.solr.core.PluginInfo; import org.apache.solr.core.SolrCore; import org.apache.solr.highlight.DefaultSolrHighlighter; import org.apache.solr.highlight.PostingsSolrHighlighter; import org.apache.solr.highlight.SolrHighlighter; import org.apache.solr.highlight.UnifiedSolrHighlighter; import org.apache.solr.request.SolrQueryRequest; import org.apache.solr.search.QParser; import org.apache.solr.search.QParserPlugin; import org.apache.solr.search.QueryParsing; import org.apache.solr.search.SyntaxError; import org.apache.solr.util.SolrPluginUtils; import org.apache.solr.util.plugin.PluginInfoInitialized; import org.apache.solr.util.plugin.SolrCoreAware; import static java.util.stream.Collectors.toMap; /** * TODO! * * * @since solr 1.3 */ public class HighlightComponent extends SearchComponent implements PluginInfoInitialized, SolrCoreAware { public enum HighlightMethod { UNIFIED("unified"), FAST_VECTOR("fastVector"), POSTINGS("postings"), ORIGINAL("original"); private static final Map<String, HighlightMethod> METHODS = Collections.unmodifiableMap( Stream.of(values()).collect(toMap(HighlightMethod::getMethodName, Function.identity()))); private final String methodName; HighlightMethod(String method) { this.methodName = method; } public String getMethodName() { return methodName; } public static HighlightMethod parse(String method) { return METHODS.get(method); } } public static final String COMPONENT_NAME = "highlight"; private PluginInfo info = PluginInfo.EMPTY_INFO; @Deprecated // DWS: in 7.0 lets restructure the abstractions/relationships private SolrHighlighter solrConfigHighlighter; /** * @deprecated instead depend on {@link #process(ResponseBuilder)} to choose the highlighter based on * {@link HighlightParams#METHOD} */ @Deprecated public static SolrHighlighter getHighlighter(SolrCore core) { HighlightComponent hl = (HighlightComponent) core.getSearchComponents() .get(HighlightComponent.COMPONENT_NAME); return hl == null ? null : hl.getHighlighter(); } @Deprecated public SolrHighlighter getHighlighter() { return solrConfigHighlighter; } @Override public void init(PluginInfo info) { this.info = info; } @Override public void prepare(ResponseBuilder rb) throws IOException { SolrParams params = rb.req.getParams(); rb.doHighlights = solrConfigHighlighter.isHighlightingEnabled(params); if (rb.doHighlights) { rb.setNeedDocList(true); String hlq = params.get(HighlightParams.Q); String hlparser = MoreObjects.firstNonNull(params.get(HighlightParams.QPARSER), params.get(QueryParsing.DEFTYPE, QParserPlugin.DEFAULT_QTYPE)); if (hlq != null) { try { QParser parser = QParser.getParser(hlq, hlparser, rb.req); rb.setHighlightQuery(parser.getHighlightQuery()); } catch (SyntaxError e) { throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, e); } } } } @Override public void inform(SolrCore core) { List<PluginInfo> children = info.getChildren("highlighting"); if (children.isEmpty()) { DefaultSolrHighlighter defHighlighter = new DefaultSolrHighlighter(core); defHighlighter.init(PluginInfo.EMPTY_INFO); solrConfigHighlighter = defHighlighter; } else { solrConfigHighlighter = core.createInitInstance(children.get(0), SolrHighlighter.class, null, DefaultSolrHighlighter.class.getName()); } } @Override public void process(ResponseBuilder rb) throws IOException { if (rb.doHighlights) { SolrQueryRequest req = rb.req; SolrParams params = req.getParams(); SolrHighlighter highlighter = getHighlighter(params); //TODO: get from builder by default? String[] defaultHighlightFields = rb.getQparser() != null ? rb.getQparser().getDefaultHighlightFields() : null; Query highlightQuery = rb.getHighlightQuery(); if (highlightQuery == null) { if (rb.getQparser() != null) { try { highlightQuery = rb.getQparser().getHighlightQuery(); rb.setHighlightQuery(highlightQuery); } catch (Exception e) { throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, e); } } else { highlightQuery = rb.getQuery(); rb.setHighlightQuery(highlightQuery); } } // No highlighting if there is no query -- consider q.alt=*:* if (highlightQuery != null) { NamedList sumData = highlighter.doHighlighting(rb.getResults().docList, highlightQuery, req, defaultHighlightFields); if (sumData != null) { // TODO ???? add this directly to the response? rb.rsp.add(highlightingResponseField(), convertHighlights(sumData)); } } } } protected SolrHighlighter getHighlighter(SolrParams params) { HighlightMethod method = HighlightMethod.parse(params.get(HighlightParams.METHOD)); if (method == null) { return solrConfigHighlighter; } switch (method) { case UNIFIED: if (solrConfigHighlighter instanceof UnifiedSolrHighlighter) { return solrConfigHighlighter; } return new UnifiedSolrHighlighter(); // TODO cache one? case POSTINGS: if (solrConfigHighlighter instanceof PostingsSolrHighlighter) { return solrConfigHighlighter; } return new PostingsSolrHighlighter(); // TODO cache one? case FAST_VECTOR: // fall-through case ORIGINAL: if (solrConfigHighlighter instanceof DefaultSolrHighlighter) { return solrConfigHighlighter; } else { throw new SolrException(SolrException.ErrorCode.SERVER_ERROR, "In order to use " + HighlightParams.METHOD + "=" + method.getMethodName() + " the configured" + " highlighter in solrconfig must be " + DefaultSolrHighlighter.class); } default: throw new AssertionError(); } } @Override public void modifyRequest(ResponseBuilder rb, SearchComponent who, ShardRequest sreq) { if (!rb.doHighlights) return; // Turn on highlighting only only when retrieving fields if ((sreq.purpose & ShardRequest.PURPOSE_GET_FIELDS) != 0) { sreq.purpose |= ShardRequest.PURPOSE_GET_HIGHLIGHTS; // should already be true... sreq.params.set(HighlightParams.HIGHLIGHT, "true"); } else { sreq.params.set(HighlightParams.HIGHLIGHT, "false"); } } @Override public void handleResponses(ResponseBuilder rb, ShardRequest sreq) { } @Override public void finishStage(ResponseBuilder rb) { if (rb.doHighlights && rb.stage == ResponseBuilder.STAGE_GET_FIELDS) { final Object[] objArr = newHighlightsArray(rb.resultIds.size()); final String highlightingResponseField = highlightingResponseField(); // TODO: make a generic routine to do automatic merging of id keyed data for (ShardRequest sreq : rb.finished) { if ((sreq.purpose & ShardRequest.PURPOSE_GET_HIGHLIGHTS) == 0) continue; for (ShardResponse srsp : sreq.responses) { if (srsp.getException() != null) { // can't expect the highlight content if there was an exception for this request // this should only happen when using shards.tolerant=true continue; } Object hl = srsp.getSolrResponse().getResponse().get(highlightingResponseField); addHighlights(objArr, hl, rb.resultIds); } } rb.rsp.add(highlightingResponseField, getAllHighlights(objArr)); } } //////////////////////////////////////////// /// SolrInfoBean //////////////////////////////////////////// @Override public String getDescription() { return "Highlighting"; } @Override public Category getCategory() { return Category.HIGHLIGHTER; } //////////////////////////////////////////// /// highlighting response collation //////////////////////////////////////////// protected String highlightingResponseField() { return "highlighting"; } protected Object convertHighlights(NamedList hl) { return hl; } protected Object[] newHighlightsArray(int size) { return new NamedList.NamedListEntry[size]; } protected void addHighlights(Object[] objArr, Object obj, Map<Object, ShardDoc> resultIds) { Map.Entry<String, Object>[] arr = (Map.Entry<String, Object>[]) objArr; NamedList hl = (NamedList) obj; SolrPluginUtils.copyNamedListIntoArrayByDocPosInResponse(hl, resultIds, arr); } protected Object getAllHighlights(Object[] objArr) { final Map.Entry<String, Object>[] arr = (Map.Entry<String, Object>[]) objArr; // remove nulls in case not all docs were able to be retrieved return SolrPluginUtils.removeNulls(arr, new SimpleOrderedMap<>()); } }