| /* |
| * 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.lucene.queryparser.flexible.standard; |
| |
| import org.apache.lucene.analysis.Analyzer; |
| import org.apache.lucene.queryparser.flexible.core.QueryNodeException; |
| import org.apache.lucene.search.BooleanClause; |
| import org.apache.lucene.search.BooleanQuery; |
| import org.apache.lucene.search.Query; |
| |
| /** |
| * This class defines utility methods to (help) parse query strings into |
| * {@link Query} objects. |
| */ |
| final public class QueryParserUtil { |
| |
| /** |
| * Parses a query which searches on the fields specified. |
| * <p> |
| * If x fields are specified, this effectively constructs: |
| * |
| * <pre> |
| * <code> |
| * (field1:query1) (field2:query2) (field3:query3)...(fieldx:queryx) |
| * </code> |
| * </pre> |
| * |
| * @param queries |
| * Queries strings to parse |
| * @param fields |
| * Fields to search on |
| * @param analyzer |
| * Analyzer to use |
| * @throws IllegalArgumentException |
| * if the length of the queries array differs from the length of the |
| * fields array |
| */ |
| public static Query parse(String[] queries, String[] fields, Analyzer analyzer) |
| throws QueryNodeException { |
| if (queries.length != fields.length) |
| throw new IllegalArgumentException("queries.length != fields.length"); |
| BooleanQuery.Builder bQuery = new BooleanQuery.Builder(); |
| |
| StandardQueryParser qp = new StandardQueryParser(); |
| qp.setAnalyzer(analyzer); |
| |
| for (int i = 0; i < fields.length; i++) { |
| Query q = qp.parse(queries[i], fields[i]); |
| |
| if (q != null) { // q never null, just being defensive |
| bQuery.add(q, BooleanClause.Occur.SHOULD); |
| } |
| } |
| return bQuery.build(); |
| } |
| |
| /** |
| * Parses a query, searching on the fields specified. Use this if you need to |
| * specify certain fields as required, and others as prohibited. |
| * <p> |
| * |
| * Usage: |
| * <pre class="prettyprint"> |
| * <code> |
| * String[] fields = {"filename", "contents", "description"}; |
| * BooleanClause.Occur[] flags = {BooleanClause.Occur.SHOULD, |
| * BooleanClause.Occur.MUST, |
| * BooleanClause.Occur.MUST_NOT}; |
| * MultiFieldQueryParser.parse("query", fields, flags, analyzer); |
| * </code> |
| * </pre> |
| *<p> |
| * The code above would construct a query: |
| * |
| * <pre> |
| * <code> |
| * (filename:query) +(contents:query) -(description:query) |
| * </code> |
| * </pre> |
| * |
| * @param query |
| * Query string to parse |
| * @param fields |
| * Fields to search on |
| * @param flags |
| * Flags describing the fields |
| * @param analyzer |
| * Analyzer to use |
| * @throws IllegalArgumentException |
| * if the length of the fields array differs from the length of the |
| * flags array |
| */ |
| public static Query parse(String query, String[] fields, |
| BooleanClause.Occur[] flags, Analyzer analyzer) throws QueryNodeException { |
| if (fields.length != flags.length) |
| throw new IllegalArgumentException("fields.length != flags.length"); |
| BooleanQuery.Builder bQuery = new BooleanQuery.Builder(); |
| |
| StandardQueryParser qp = new StandardQueryParser(); |
| qp.setAnalyzer(analyzer); |
| |
| for (int i = 0; i < fields.length; i++) { |
| Query q = qp.parse(query, fields[i]); |
| |
| if (q != null) { // q never null, just being defensive |
| bQuery.add(q, flags[i]); |
| } |
| } |
| return bQuery.build(); |
| } |
| |
| /** |
| * Parses a query, searching on the fields specified. Use this if you need to |
| * specify certain fields as required, and others as prohibited. |
| * <p> |
| * |
| * Usage: |
| * <pre class="prettyprint"> |
| * <code> |
| * String[] query = {"query1", "query2", "query3"}; |
| * String[] fields = {"filename", "contents", "description"}; |
| * BooleanClause.Occur[] flags = {BooleanClause.Occur.SHOULD, |
| * BooleanClause.Occur.MUST, |
| * BooleanClause.Occur.MUST_NOT}; |
| * MultiFieldQueryParser.parse(query, fields, flags, analyzer); |
| * </code> |
| * </pre> |
| *<p> |
| * The code above would construct a query: |
| * |
| * <pre> |
| * <code> |
| * (filename:query1) +(contents:query2) -(description:query3) |
| * </code> |
| * </pre> |
| * |
| * @param queries |
| * Queries string to parse |
| * @param fields |
| * Fields to search on |
| * @param flags |
| * Flags describing the fields |
| * @param analyzer |
| * Analyzer to use |
| * @throws IllegalArgumentException |
| * if the length of the queries, fields, and flags array differ |
| */ |
| public static Query parse(String[] queries, String[] fields, |
| BooleanClause.Occur[] flags, Analyzer analyzer) throws QueryNodeException { |
| if (!(queries.length == fields.length && queries.length == flags.length)) |
| throw new IllegalArgumentException( |
| "queries, fields, and flags array have have different length"); |
| BooleanQuery.Builder bQuery = new BooleanQuery.Builder(); |
| |
| StandardQueryParser qp = new StandardQueryParser(); |
| qp.setAnalyzer(analyzer); |
| |
| for (int i = 0; i < fields.length; i++) { |
| Query q = qp.parse(queries[i], fields[i]); |
| |
| if (q != null) { // q never null, just being defensive |
| bQuery.add(q, flags[i]); |
| } |
| } |
| return bQuery.build(); |
| } |
| |
| /** |
| * Returns a String where those characters that TextParser expects to be |
| * escaped are escaped by a preceding <code>\</code>. |
| */ |
| public static String escape(String s) { |
| StringBuilder sb = new StringBuilder(); |
| for (int i = 0; i < s.length(); i++) { |
| char c = s.charAt(i); |
| // These characters are part of the query syntax and must be escaped |
| if (c == '\\' || c == '+' || c == '-' || c == '!' || c == '(' || c == ')' |
| || c == ':' || c == '^' || c == '[' || c == ']' || c == '\"' |
| || c == '{' || c == '}' || c == '~' || c == '*' || c == '?' |
| || c == '|' || c == '&' || c == '/') { |
| sb.append('\\'); |
| } |
| sb.append(c); |
| } |
| return sb.toString(); |
| } |
| |
| } |