| /* |
| * 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. |
| */ |
| |
| /** |
| * Core classes of the flexible query parser framework. |
| * |
| * <h2>Flexible Query Parser</h2> |
| * |
| * <p> |
| * This package contains the necessary classes to implement a query parser. |
| * |
| * <p> |
| * A query parser is divided in at least 2 phases, text parsing and query building, and one optional phase called query processing. |
| * |
| * <h3>First Phase: Text Parsing</h3> |
| * <p> |
| * The text parsing phase is performed by a text parser, which implements {@link org.apache.lucene.queryparser.flexible.core.parser.SyntaxParser} interface. |
| * A text parser is responsible to get a query string and convert it to a {@link org.apache.lucene.queryparser.flexible.core.nodes.QueryNode} tree, |
| * which is an object structure that represents the elements defined in the query string. |
| * |
| * <h3>Second (optional) Phase: Query Processing</h3> |
| * <p> |
| * The query processing phase is performed by a query processor, which implements {@link org.apache.lucene.queryparser.flexible.core.processors.QueryNodeProcessor}. |
| * A query processor is responsible to perform any processing on a {@link org.apache.lucene.queryparser.flexible.core.nodes.QueryNode} tree. This phase |
| * is optional and is used only if an extra processing, validation, query expansion, etc needs to be performed in a {@link org.apache.lucene.queryparser.flexible.core.nodes.QueryNode} tree. |
| * The {@link org.apache.lucene.queryparser.flexible.core.nodes.QueryNode} tree can be either be generated by a text parser or programmatically created. |
| * |
| * <h3>Third Phase: Query Building</h3> |
| * <p> |
| * The query building phase is performed by a query builder, which implements {@link org.apache.lucene.queryparser.flexible.core.builders.QueryBuilder}. |
| * A query builder is responsible to convert a {@link org.apache.lucene.queryparser.flexible.core.nodes.QueryNode} tree into an arbitrary object, which |
| * is usually used to be executed against a search index. |
| */ |
| package org.apache.lucene.queryparser.flexible.core; |
