| /* |
| * 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; |
| |
| import org.jetbrains.annotations.NotNull; |
| |
| /** |
| * 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 NOT 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) { |
| // the language is case sensitive |
| return "xpath".equals(language); |
| } |
| // the query is not, at least SQL is not |
| 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("measure".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 before |
| * keywords such as "where", "and", and "or". |
| * |
| * @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(@NotNull 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 =='[') { |
| if (i + 1 < buff.length() && buff.charAt(i + 1) > ' ') { |
| buff.insert(i + 1, "\n "); |
| i += 3; |
| } |
| } else if (c == '\n') { |
| // already formatted |
| while (++i < buff.length() && buff.charAt(i) == ' ') { |
| // skip |
| } |
| i--; |
| } 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 |
| } |
| } else if (c == '\n') { |
| // already formatted |
| while (++i < buff.length() && buff.charAt(i) == ' ') { |
| // skip |
| } |
| i--; |
| } else if (c == ' ') { |
| String sub = buff.substring(i, Math.min(i + 10, buff.length())); |
| if (startsWithIgnoreCase(sub, " and ") |
| || startsWithIgnoreCase(sub, " or ") |
| || startsWithIgnoreCase(sub, " union ") |
| || startsWithIgnoreCase(sub, " from ") |
| || startsWithIgnoreCase(sub, " where ") |
| || startsWithIgnoreCase(sub, " order by ") |
| || startsWithIgnoreCase(sub, " 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 boolean startsWithIgnoreCase(String s, String prefix) { |
| return s.regionMatches(true, 0, prefix, 0, prefix.length()); |
| } |
| |
| } |