简单的facet实例
public class SimpleFacetsExample {
private final Directory indexDir = new RAMDirectory();
private final Directory taxoDir = new RAMDirectory();
private final FacetsConfig config = new FacetsConfig();
/** Empty constructor */
public SimpleFacetsExample() {
config.setHierarchical("Publish Date", true);
}
/** Build the example index. */
private void index() throws IOException {
IndexWriter indexWriter = new IndexWriter(indexDir, new IndexWriterConfig(
new WhitespaceAnalyzer()).setOpenMode(OpenMode.CREATE));
// Writes facet ords to a separate directory from the main index
DirectoryTaxonomyWriter taxoWriter = new DirectoryTaxonomyWriter(taxoDir);
Document doc = new Document();
doc.add(new FacetField("Author", "Bob"));
doc.add(new FacetField("Publish Date", "2010", "10", "15"));
indexWriter.addDocument(config.build(taxoWriter, doc));
doc = new Document();
doc.add(new FacetField("Author", "Lisa"));
doc.add(new FacetField("Publish Date", "2010", "10", "20"));
indexWriter.addDocument(config.build(taxoWriter, doc));
doc = new Document();
doc.add(new FacetField("Author", "Lisa"));
doc.add(new FacetField("Publish Date", "2012", "1", "1"));
indexWriter.addDocument(config.build(taxoWriter, doc));
doc = new Document();
doc.add(new FacetField("Author", "Susan"));
doc.add(new FacetField("Publish Date", "2012", "1", "7"));
indexWriter.addDocument(config.build(taxoWriter, doc));
doc = new Document();
doc.add(new FacetField("Author", "Frank"));
doc.add(new FacetField("Publish Date", "1999", "5", "5"));
indexWriter.addDocument(config.build(taxoWriter, doc));
indexWriter.close();
taxoWriter.close();
}
/** User runs a query and counts facets. */
private List<FacetResult> facetsWithSearch() throws IOException {
DirectoryReader indexReader = DirectoryReader.open(indexDir);
IndexSearcher searcher = new IndexSearcher(indexReader);
TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir);
FacetsCollector fc = new FacetsCollector();
// MatchAllDocsQuery is for "browsing" (counts facets
// for all non-deleted docs in the index); normally
// you'd use a "normal" query:
FacetsCollector.search(searcher, new MatchAllDocsQuery(), 10, fc);
// Retrieve results
List<FacetResult> results = new ArrayList<>();
// Count both "Publish Date" and "Author" dimensions
Facets facets = new FastTaxonomyFacetCounts(taxoReader, config, fc);
results.add(facets.getTopChildren(10, "Author"));
results.add(facets.getTopChildren(10, "Publish Date"));
indexReader.close();
taxoReader.close();
return results;
}
/** User runs a query and counts facets only without collecting the matching documents.*/
private List<FacetResult> facetsOnly() throws IOException {
DirectoryReader indexReader = DirectoryReader.open(indexDir);
IndexSearcher searcher = new IndexSearcher(indexReader);
TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir);
FacetsCollector fc = new FacetsCollector();
// MatchAllDocsQuery is for "browsing" (counts facets
// for all non-deleted docs in the index); normally
// you'd use a "normal" query:
searcher.search(new MatchAllDocsQuery(), fc);
// Retrieve results
List<FacetResult> results = new ArrayList<>();
// Count both "Publish Date" and "Author" dimensions
Facets facets = new FastTaxonomyFacetCounts(taxoReader, config, fc);
results.add(facets.getTopChildren(10, "Author"));
results.add(facets.getTopChildren(10, "Publish Date"));
indexReader.close();
taxoReader.close();
return results;
}
/** User drills down on 'Publish Date/2010', and we
* return facets for 'Author' */
private FacetResult drillDown() throws IOException {
DirectoryReader indexReader = DirectoryReader.open(indexDir);
IndexSearcher searcher = new IndexSearcher(indexReader);
TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir);
// Passing no baseQuery means we drill down on all
// documents ("browse only"):
DrillDownQuery q = new DrillDownQuery(config);
// Now user drills down on Publish Date/2010:
q.add("Publish Date", "2010");
FacetsCollector fc = new FacetsCollector();
FacetsCollector.search(searcher, q, 10, fc);
// Retrieve results
Facets facets = new FastTaxonomyFacetCounts(taxoReader, config, fc);
FacetResult result = facets.getTopChildren(10, "Author");
indexReader.close();
taxoReader.close();
return result;
}
/** User drills down on 'Publish Date/2010', and we
* return facets for both 'Publish Date' and 'Author',
* using DrillSideways. */
private List<FacetResult> drillSideways() throws IOException {
DirectoryReader indexReader = DirectoryReader.open(indexDir);
IndexSearcher searcher = new IndexSearcher(indexReader);
TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir);
// Passing no baseQuery means we drill down on all
// documents ("browse only"):
DrillDownQuery q = new DrillDownQuery(config);
// Now user drills down on Publish Date/2010:
q.add("Publish Date", "2010");
DrillSideways ds = new DrillSideways(searcher, config, taxoReader);
DrillSidewaysResult result = ds.search(q, 10);
// Retrieve results
List<FacetResult> facets = result.facets.getAllDims(10);
indexReader.close();
taxoReader.close();
return facets;
}
/** Runs the search example. */
public List<FacetResult> runFacetOnly() throws IOException {
index();
return facetsOnly();
}
/** Runs the search example. */
public List<FacetResult> runSearch() throws IOException {
index();
return facetsWithSearch();
}
/** Runs the drill-down example. */
public FacetResult runDrillDown() throws IOException {
index();
return drillDown();
}
/** Runs the drill-sideways example. */
public List<FacetResult> runDrillSideways() throws IOException {
index();
return drillSideways();
}
/** Runs the search and drill-down examples and prints the results. */
public static void main(String[] args) throws Exception {
System.out.println("Facet counting example:");
System.out.println("-----------------------");
SimpleFacetsExample example = new SimpleFacetsExample();
List<FacetResult> results1 = example.runFacetOnly();
System.out.println("Author: " + results1.get(0));
System.out.println("Publish Date: " + results1.get(1));
System.out.println("Facet counting example (combined facets and search):");
System.out.println("-----------------------");
List<FacetResult> results = example.runSearch();
System.out.println("Author: " + results.get(0));
System.out.println("Publish Date: " + results.get(1));
System.out.println("Facet drill-down example (Publish Date/2010):");
System.out.println("---------------------------------------------");
System.out.println("Author: " + example.runDrillDown());
System.out.println("Facet drill-sideways example (Publish Date/2010):");
System.out.println("---------------------------------------------");
for(FacetResult result : example.runDrillSideways()) {
System.out.println(result);
}
}
}查询及其关系
查询
/** Lower-level search API.
*
* <p>{@link LeafCollector#collect(int)} is called for every matching document.
*
* @throws BooleanQuery.TooManyClauses If a query would exceed
* {@link BooleanQuery#getMaxClauseCount()} clauses.
*/
public void search(Query query, Collector results)
throws IOException {
query = rewrite(query);
search(leafContexts, createWeight(query, results.needsScores(), 1), results);
}
关系