| /* |
| * 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.lucene.analysis.ko.util; |
| |
| import java.util.ArrayList; |
| import java.util.regex.Matcher; |
| import java.util.regex.Pattern; |
| |
| /** Utility class for parsing CSV text */ |
| public final class CSVUtil { |
| private static final char QUOTE = '"'; |
| |
| private static final char COMMA = ','; |
| |
| private static final Pattern QUOTE_REPLACE_PATTERN = Pattern.compile("^\"([^\"]+)\"$"); |
| |
| private static final String ESCAPED_QUOTE = "\"\""; |
| |
| private CSVUtil() {} // no instance!!! |
| |
| /** |
| * Parse CSV line |
| * |
| * @param line line containing csv-encoded data |
| * @return Array of values |
| */ |
| public static String[] parse(String line) { |
| boolean insideQuote = false; |
| ArrayList<String> result = new ArrayList<>(); |
| int quoteCount = 0; |
| StringBuilder sb = new StringBuilder(); |
| for (int i = 0; i < line.length(); i++) { |
| char c = line.charAt(i); |
| |
| if (c == QUOTE) { |
| insideQuote = !insideQuote; |
| quoteCount++; |
| } |
| |
| if (c == COMMA && !insideQuote) { |
| String value = sb.toString(); |
| value = unQuoteUnEscape(value); |
| result.add(value); |
| sb.setLength(0); |
| continue; |
| } |
| |
| sb.append(c); |
| } |
| |
| result.add(sb.toString()); |
| |
| // Validate |
| if (quoteCount % 2 != 0) { |
| return new String[0]; |
| } |
| |
| return result.toArray(new String[0]); |
| } |
| |
| private static String unQuoteUnEscape(String original) { |
| String result = original; |
| |
| // Unquote |
| if (result.indexOf('\"') >= 0) { |
| Matcher m = QUOTE_REPLACE_PATTERN.matcher(original); |
| if (m.matches()) { |
| result = m.group(1); |
| } |
| |
| // Unescape |
| if (result.contains(ESCAPED_QUOTE)) { |
| result = result.replace(ESCAPED_QUOTE, "\""); |
| } |
| } |
| |
| return result; |
| } |
| } |