--- /dev/null
+package org.apache.lucene.queryParser.standard;
+
+/**
+ * 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.
+ */
+
+import org.apache.lucene.analysis.Analyzer;
+import org.apache.lucene.queryParser.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 bQuery = new BooleanQuery();
+
+ 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
+ (!(q instanceof BooleanQuery) || ((BooleanQuery) q).getClauses().length > 0)) {
+ bQuery.add(q, BooleanClause.Occur.SHOULD);
+ }
+ }
+ return bQuery;
+ }
+
+ /**
+ * Parses a query, searching on the fields specified. Use this if you need to
+ * specify certain fields as required, and others as prohibited.
+ * <p>
+ *
+ * <pre>
+ * Usage:
+ * <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 bQuery = new BooleanQuery();
+
+ 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
+ (!(q instanceof BooleanQuery) || ((BooleanQuery) q).getClauses().length > 0)) {
+ bQuery.add(q, flags[i]);
+ }
+ }
+ return bQuery;
+ }
+
+ /**
+ * Parses a query, searching on the fields specified. Use this if you need to
+ * specify certain fields as required, and others as prohibited.
+ * <p>
+ *
+ * <pre>
+ * Usage:
+ * <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 bQuery = new BooleanQuery();
+
+ 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
+ (!(q instanceof BooleanQuery) || ((BooleanQuery) q).getClauses().length > 0)) {
+ bQuery.add(q, flags[i]);
+ }
+ }
+ return bQuery;
+ }
+
+ /**
+ * 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 == '&') {
+ sb.append('\\');
+ }
+ sb.append(c);
+ }
+ return sb.toString();
+ }
+
+}
fnp / pylucene.git / blobdiff