IndexWriter class provides ‘addDocument’ method, it is used to add document to an index.
Signature
public long addDocument(Iterable<? extends IndexableField> doc) throws IOException
Example
indexWriter.addDocument(document);
'addDocument' method periodically flushes pending documentscto the Directory, andcalso periodically triggers segment merges in the indexcaccording to the MergePolicy in use.
Find the below working application.
DocumentUtil.java
package com.sample.app.util;
import java.util.Arrays;
import java.util.List;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.TextField;
public class DocumentUtil {
private static Document getDocument(String id, String title, String description, String blog) {
Document doc = new Document();
doc.add(new TextField("id", id, Field.Store.YES));
doc.add(new TextField("title", title, Field.Store.YES));
doc.add(new TextField("description", description, Field.Store.NO));
doc.add(new TextField("blog", blog, Field.Store.YES));
return doc;
}
public static List<Document> getDocuments() {
Document doc1 = getDocument("1", "JavaWorld",
"The original independent resource for Java developers, architects, and managers.", " javaworld.com");
Document doc2 = getDocument("2", "Oracle Blogs | The Java Source",
" Java powers more than 4.5 billion devices including 800 million computers and 1.5 billion cell phones. If you love Java, this is the blog you must follow.",
"blogs.oracle.com/java");
Document doc3 = getDocument("3", "A Java geek",
"Nicolas Fränkel's blog. IT architect focusing on Java, Java EE, and their surrounding ecosystems. He is a trainer, book writer, speaker & blogger.",
"blog.frankel.ch");
Document doc4 = getDocument("4", "Self Learning Java", "Learn Java fundamentals and other java libraries",
"self-learning-java-tutorial.blogspot.com");
return Arrays.asList(doc1, doc2, doc3, doc4);
}
}
App.java
package com.sample.app;
import java.io.File;
import java.io.IOException;
import java.util.List;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.MMapDirectory;
import org.apache.lucene.store.NoLockFactory;
import org.apache.lucene.util.QueryBuilder;
import com.sample.app.util.DocumentUtil;
public class App {
public static void main(String args[]) throws IOException {
Analyzer analyzer = new StandardAnalyzer();
IndexWriterConfig config = new IndexWriterConfig(analyzer);
Directory directory = new MMapDirectory(new File("/Users/Shared/lucene").toPath(), NoLockFactory.INSTANCE);
try (IndexWriter indexWriter = new IndexWriter(directory, config)) {
List<Document> documents = DocumentUtil.getDocuments();
for (Document document : documents) {
indexWriter.addDocument(document);
}
}
QueryBuilder queryBuilder = new QueryBuilder(analyzer);
Query query = queryBuilder.createMinShouldMatchQuery("description", "Professional java developers", 0.7f);
int maxHitsPerPage = 10;
try (IndexReader indexReader = DirectoryReader.open(directory)) {
IndexSearcher indexSearcher = new IndexSearcher(indexReader);
TopDocs docs = indexSearcher.search(query, maxHitsPerPage);
ScoreDoc[] hits = docs.scoreDocs;
System.out.println("Total Hits: " + docs.totalHits);
System.out.println("Results: ");
for (int i = 0; i < hits.length; i++) {
Document document = indexSearcher.doc(hits[i].doc);
System.out.println("Title: " + document.get("title"));
}
}
}
}
Output
Total Hits: 1 hits Results: Title: JavaWorld
No comments:
Post a Comment