package org.apache.lucene.queryparser.flexible.spans;
/*
* 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
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import javax.management.Query;
import org.apache.lucene.queryparser.flexible.core.config.QueryConfigHandler;
import org.apache.lucene.queryparser.flexible.core.nodes.OrQueryNode;
import org.apache.lucene.queryparser.flexible.core.nodes.QueryNode;
import org.apache.lucene.queryparser.flexible.core.parser.SyntaxParser;
import org.apache.lucene.queryparser.flexible.core.processors.QueryNodeProcessorPipeline;
import org.apache.lucene.queryparser.flexible.standard.parser.StandardSyntaxParser;
import org.apache.lucene.search.spans.SpanQuery;
import org.apache.lucene.search.spans.SpanTermQuery;
import org.apache.lucene.util.LuceneTestCase;
/**
* This test case demonstrates how the new query parser can be used.<br/>
* <br/>
*
* It tests queries likes "term", "field:term" "term1 term2" "term1 OR term2",
* which are all already supported by the current syntax parser (
* {@link StandardSyntaxParser}).<br/>
* <br/>
*
* The goals is to create a new query parser that supports only the pair
* "field:term" or a list of pairs separated or not by an OR operator, and from
* this query generate {@link SpanQuery} objects instead of the regular
* {@link Query} objects. Basically, every pair will be converted to a
* {@link SpanTermQuery} object and if there are more than one pair they will be
* grouped by an {@link OrQueryNode}.<br/>
* <br/>
*
* Another functionality that will be added is the ability to convert every
* field defined in the query to an unique specific field.<br/>
* <br/>
*
* The query generation is divided in three different steps: parsing (syntax),
* processing (semantic) and building.<br/>
* <br/>
*
* The parsing phase, as already mentioned will be performed by the current
* query parser: {@link StandardSyntaxParser}.<br/>
* <br/>
*
* The processing phase will be performed by a processor pipeline which is
* compound by 2 processors: {@link SpansValidatorQueryNodeProcessor} and
* {@link UniqueFieldQueryNodeProcessor}.
*
* <pre>
*
* {@link SpansValidatorQueryNodeProcessor}: as it's going to use the current
* query parser to parse the syntax, it will support more features than we want,
* this processor basically validates the query node tree generated by the parser
* and just let got through the elements we want, all the other elements as
* wildcards, range queries, etc...if found, an exception is thrown.
*
* {@link UniqueFieldQueryNodeProcessor}: this processor will take care of reading
* what is the "unique field" from the configuration and convert every field defined
* in every pair to this "unique field". For that, a {@link SpansQueryConfigHandler} is
* used, which has the {@link UniqueFieldAttribute} defined in it.
* </pre>
*
* The building phase is performed by the {@link SpansQueryTreeBuilder}, which
* basically contains a map that defines which builder will be used to generate
* {@link SpanQuery} objects from {@link QueryNode} objects.<br/>
* <br/>
*
* @see TestSpanQueryParser for a more advanced example
*
* @see SpansQueryConfigHandler
* @see SpansQueryTreeBuilder
* @see SpansValidatorQueryNodeProcessor
* @see SpanOrQueryNodeBuilder
* @see SpanTermQueryNodeBuilder
* @see StandardSyntaxParser
* @see UniqueFieldQueryNodeProcessor
* @see UniqueFieldAttribute
*
*/
public class TestSpanQueryParserSimpleSample extends LuceneTestCase {
public void testBasicDemo() throws Exception {
SyntaxParser queryParser = new StandardSyntaxParser();
// convert the CharSequence into a QueryNode tree
QueryNode queryTree = queryParser.parse("body:text", null);
// create a config handler with a attribute used in
// UniqueFieldQueryNodeProcessor
QueryConfigHandler spanQueryConfigHandler = new SpansQueryConfigHandler();
spanQueryConfigHandler.set(SpansQueryConfigHandler.UNIQUE_FIELD, "index");
// set up the processor pipeline with the ConfigHandler
// and create the pipeline for this simple demo
QueryNodeProcessorPipeline spanProcessorPipeline = new QueryNodeProcessorPipeline(
spanQueryConfigHandler);
// @see SpansValidatorQueryNodeProcessor
spanProcessorPipeline.add(new SpansValidatorQueryNodeProcessor());
// @see UniqueFieldQueryNodeProcessor
spanProcessorPipeline.add(new UniqueFieldQueryNodeProcessor());
// print to show out the QueryNode tree before being processed
if (VERBOSE) System.out.println(queryTree);
// Process the QueryTree using our new Processors
queryTree = spanProcessorPipeline.process(queryTree);
// print to show out the QueryNode tree after being processed
if (VERBOSE) System.out.println(queryTree);
// create a instance off the Builder
SpansQueryTreeBuilder spansQueryTreeBuilder = new SpansQueryTreeBuilder();
// convert QueryNode tree to span query Objects
SpanQuery spanquery = spansQueryTreeBuilder.build(queryTree);
assertTrue(spanquery instanceof SpanTermQuery);
assertEquals(spanquery.toString(), "index:text");
}
}