thomasmueller commented on code in PR #1187: URL: https://github.com/apache/jackrabbit-oak/pull/1187#discussion_r1381999878
########## oak-core/src/main/java/org/apache/jackrabbit/oak/query/QueryFormatter.java: ########## @@ -0,0 +1,138 @@ +/* + * 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.jackrabbit.oak.query; + +import java.util.Locale; + +/** + * Formatter for JCR queries in order to make them easier to read. Formatting is + * done on a best-effort basis. + * + * Warning: Care was taken to not add newlines inside string literals and so on, + * but there is still no guarantee that the formatted query is semantically + * equal to the original one. It is recommended to run queries that are returned + * by these methods. + */ +public class QueryFormatter { + + /** + * Detect whether the query is an XPath query. + * + * @param query the query + * @param language the language, if known, or null + * @return true if xpath + */ + public static boolean isXPath(String query, String language) { + if (language != null) { + return "xpath".equals(language); + } + query = query.trim().toLowerCase(Locale.ENGLISH); + // explain queries + if (query.startsWith("explain")) { + query = query.substring("explain".length()).trim(); + if (query.startsWith("measure")) { + query = query.substring("explain".length()).trim(); + } + } + // union queries + while (query.startsWith("(")) { + query = query.substring("(".length()).trim(); + } + if (query.startsWith("select")) { + return false; + } + return true; + } + + /** + * Format the query into a more human-readable way, by adding newlines. + * Warning: newlines are also added inside e.g. string literals. + * + * @param query the query (may not be null) + * @param language the query language, or null if unknown + * @return the formatted query + */ + public static String format(String query, String language) { + boolean xpath = isXPath(query, language); + if (xpath) { + return formatXPath(query); + } else { + return formatSQL(query); + } + } + + private static String formatXPath(String query) { + StringBuilder buff = new StringBuilder(query); + for (int i = 0; i < buff.length(); i++) { + char c = buff.charAt(i); + if (c == '\'' || c == '"') { + while (++i < buff.length() && buff.charAt(i) != c) { + // skip + } + } else if (c =='[') { + buff.insert(i + 1, "\n "); + i += 3; + } else if (c <= ' ') { + String sub = buff.substring(i, Math.min(i + 10, buff.length())); + if (sub.startsWith(" and ") + || sub.startsWith(" or ") + || sub.startsWith(" order by ") + || sub.startsWith(" option(")) { + buff.setCharAt(i, '\n'); + buff.insert(i + 1, " "); + // just skip over the whitespace - but that's OK + i += 2; + } + } + } + return buff.toString(); + } + + private static String formatSQL(String query) { + StringBuilder buff = new StringBuilder(query); + for (int i = 0; i < buff.length(); i++) { + char c = buff.charAt(i); + if (c == '\'' || c == '"') { + while (++i < buff.length() && buff.charAt(i) != c) { + // skip + } Review Comment: See the docs at https://jackrabbit.apache.org/oak/docs/query/grammar-sql2.html#static_operand and https://jackrabbit.apache.org/oak/docs/query/grammar-xpath.html#static_operand -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
