001    /*
002    // $Id: MdxValidator.java 482 2012-01-05 23:27:27Z jhyde $
003    //
004    // Licensed to Julian Hyde under one or more contributor license
005    // agreements. See the NOTICE file distributed with this work for
006    // additional information regarding copyright ownership.
007    //
008    // Julian Hyde licenses this file to you under the Apache License,
009    // Version 2.0 (the "License"); you may not use this file except in
010    // compliance with the License. You may obtain a copy of the License at:
011    //
012    // http://www.apache.org/licenses/LICENSE-2.0
013    //
014    // Unless required by applicable law or agreed to in writing, software
015    // distributed under the License is distributed on an "AS IS" BASIS,
016    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
017    // See the License for the specific language governing permissions and
018    // limitations under the License.
019    */
020    package org.olap4j.mdx.parser;
021    
022    import org.olap4j.OlapException;
023    import org.olap4j.mdx.SelectNode;
024    
025    /**
026     * Validator for the MDX query language.
027     *
028     * <p>A validator is reusable but not reentrant: you can call
029     * {@link #validateSelect(org.olap4j.mdx.SelectNode)} several times, but not at
030     * the same time from different threads.
031     *
032     * <p>To create a validator, use the
033     * {@link MdxParserFactory#createMdxValidator(org.olap4j.OlapConnection)}
034     * method.
035     *
036     * @see MdxParserFactory
037     * @see MdxParser
038     *
039     * @author jhyde
040     * @version $Id: MdxValidator.java 482 2012-01-05 23:27:27Z jhyde $
041     * @since Aug 22, 2006
042     */
043    public interface MdxValidator {
044        /**
045         * Validates an MDX SELECT statement.
046         *
047         * <p>The SelectNode representing the SELECT statement may have been
048         * created by an {@link MdxParser}, or it may have been built
049         * programmatically.
050         *
051         * <p>If the parse tree is invalid, throws an {@link OlapException}.
052         *
053         * <p>If it is valid, returns a parse tree. This parse tree may or may not
054         * be the same parse tree passed as an argument. After validation, you can
055         * ascertain the type of each node of the parse tree by calling its
056         * {@link org.olap4j.mdx.ParseTreeNode#getType()} method.
057         *
058         * @param selectNode Parse tree node representing a SELECT statement
059         *
060         * @return Validated parse tree
061         *
062         * @throws OlapException if node is invalid
063         */
064        SelectNode validateSelect(SelectNode selectNode) throws OlapException;
065    }
066    
067    // End MdxValidator.java