RAMDirectory directory = new RAMDirectory();
String[] categories = new String[] {"/Computers",
"/Computers/Mac",
"/Computers/Windows"};
IndexWriter writer = new IndexWriter(directory, new WhitespaceAnalyzer(), true);
for (int i = 0; i < categories.length; i++) {
Document doc = new Document();
doc.add(Field.Keyword("category", categories[i]));
writer.addDocument(doc);
}
writer.close();
PrefixQuery query = new PrefixQuery(new Term("category", "/Computers"));
IndexSearcher searcher = new IndexSearcher(directory);
Hits hits = searcher.search(query);
assertEquals("All documents in /Computers category and below", 3, hits.length());
query = new PrefixQuery(new Term("category", "/Computers/Mac"));
hits = searcher.search(query);
assertEquals("One in /Computers/Mac", 1, hits.length());
