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+<html>
+<head>
+ <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+</head>
+<body>
+
+Contains the 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>
+
+<p>
+A query parser is divided in at least 2 phases, text parsing and query building, and one optional phase called query processing.
+</p>
+
+<h3>First Phase: Text Parsing</h3>
+<p>
+The text parsing phase is performed by a text parser, which implements {@link org.apache.lucene.queryParser.core.parser.SyntaxParser} interface.
+A text parser is responsible to get a query string and convert it to a {@link org.apache.lucene.queryParser.core.nodes.QueryNode} tree,
+which is an object structure that represents the elements defined in the query string.
+</p>
+
+<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.core.processors.QueryNodeProcessor}.
+A query processor is responsible to perform any processing on a {@link org.apache.lucene.queryParser.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.core.nodes.QueryNode} tree.
+The {@link org.apache.lucene.queryParser.core.nodes.QueryNode} tree can be either be generated by a text parser or programmatically created.
+</p>
+
+<h3>Third Phase: Query Building</h3>
+<p>
+The query building phase is performed by a query builder, which implements {@link org.apache.lucene.queryParser.core.builders.QueryBuilder}.
+A query builder is responsible to convert a {@link org.apache.lucene.queryParser.core.nodes.QueryNode} tree into an arbitrary object, which
+is usually used to be executed against a search index.
+</p>
+
+</body>
+</html>