001 /** 002 * ======================================== 003 * JFreeReport : a free Java report library 004 * ======================================== 005 * 006 * Project Info: http://reporting.pentaho.org/ 007 * 008 * (C) Copyright 2000-2007, by Object Refinery Limited, Pentaho Corporation and Contributors. 009 * 010 * This library is free software; you can redistribute it and/or modify it under the terms 011 * of the GNU Lesser General Public License as published by the Free Software Foundation; 012 * either version 2.1 of the License, or (at your option) any later version. 013 * 014 * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; 015 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 016 * See the GNU Lesser General Public License for more details. 017 * 018 * You should have received a copy of the GNU Lesser General Public License along with this 019 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, 020 * Boston, MA 02111-1307, USA. 021 * 022 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 023 * in the United States and other countries.] 024 * 025 * ------------ 026 * $Id: CSVQuoter.java 2725 2007-04-01 18:49:29Z taqua $ 027 * ------------ 028 * (C) Copyright 2000-2005, by Object Refinery Limited. 029 * (C) Copyright 2005-2007, by Pentaho Corporation. 030 */ 031 032 package org.jfree.report.util; 033 034 /** 035 * The <code>CSVQuoter</code> is a helper class to encode a string for the CSV file 036 * format. 037 * 038 * @author Thomas Morgner. 039 */ 040 public class CSVQuoter 041 { 042 /** 043 * The separator used in the CSV file. 044 */ 045 private char separator; 046 /** 047 * The quoting character or a single quote. 048 */ 049 private char quate; 050 /** 051 * The double quote. This is a string containing the quate two times. 052 */ 053 private String doubleQuate; 054 055 /** 056 * Creates a new CSVQuoter, which uses a comma as the default separator. 057 */ 058 public CSVQuoter () 059 { 060 this(',', '"'); 061 } 062 063 /** 064 * Creates a new <code>CSVQuoter</code>, which uses the defined separator. 065 * 066 * @param separator the separator. 067 * @throws NullPointerException if the given separator is <code>null</code>. 068 */ 069 public CSVQuoter (final char separator) 070 { 071 this(separator, '"'); 072 } 073 074 /** 075 * Creates a new CSVQuoter with the given separator and quoting character. 076 * 077 * @param separator the separator 078 * @param quate the quoting character 079 */ 080 public CSVQuoter (final char separator, final char quate) 081 { 082 this.separator = separator; 083 this.quate = quate; 084 this.doubleQuate = "" + quate + quate; 085 } 086 087 /** 088 * Encodes the string, so that the string can safely be used in CSV files. If the string 089 * does not need quoting, the original string is returned unchanged. 090 * 091 * @param original the unquoted string. 092 * @return The quoted string 093 */ 094 public String doQuoting (final String original) 095 { 096 if (isQuotingNeeded(original)) 097 { 098 final StringBuffer retval = new StringBuffer(); 099 retval.append(quate); 100 applyQuote(retval, original); 101 retval.append(quate); 102 return retval.toString(); 103 } 104 else 105 { 106 return original; 107 } 108 } 109 110 /** 111 * Decodes the string, so that all escape sequences get removed. If the string was not 112 * quoted, then the string is returned unchanged. 113 * 114 * @param nativeString the quoted string. 115 * @return The unquoted string. 116 */ 117 public String undoQuoting (final String nativeString) 118 { 119 if (isQuotingNeeded(nativeString)) 120 { 121 final StringBuffer b = new StringBuffer(nativeString.length()); 122 final int length = nativeString.length() - 1; 123 int start = 1; 124 125 int pos = start; 126 while (pos != -1) 127 { 128 pos = nativeString.indexOf(doubleQuate, start); 129 if (pos == -1) 130 { 131 b.append(nativeString.substring(start, length)); 132 } 133 else 134 { 135 b.append(nativeString.substring(start, pos)); 136 start = pos + 1; 137 } 138 } 139 return b.toString(); 140 } 141 else 142 { 143 return nativeString; 144 } 145 } 146 147 /** 148 * Tests, whether this string needs to be quoted. A string is encoded if the string 149 * contains a newline character, a quote character or the defined separator. 150 * 151 * @param str the string that should be tested. 152 * @return true, if quoting needs to be applied, false otherwise. 153 */ 154 private boolean isQuotingNeeded (final String str) 155 { 156 if (str.indexOf(separator) != -1) 157 { 158 return true; 159 } 160 if (str.indexOf('\n') != -1) 161 { 162 return true; 163 } 164 if (str.indexOf(quate, 1) != -1) 165 { 166 return true; 167 } 168 return false; 169 } 170 171 /** 172 * Applies the quoting to a given string, and stores the result in the StringBuffer 173 * <code>b</code>. 174 * 175 * @param b the result buffer 176 * @param original the string, that should be quoted. 177 */ 178 private void applyQuote (final StringBuffer b, final String original) 179 { 180 // This solution needs improvements. Copy blocks instead of single 181 // characters. 182 final int length = original.length(); 183 184 for (int i = 0; i < length; i++) 185 { 186 final char c = original.charAt(i); 187 if (c == quate) 188 { 189 b.append(doubleQuate); 190 } 191 else 192 { 193 b.append(c); 194 } 195 } 196 } 197 198 /** 199 * Gets the separator used in this quoter and the CSV file. 200 * 201 * @return the separator (never <code>null</code>). 202 */ 203 public char getSeparator () 204 { 205 return separator; 206 } 207 208 /** 209 * Returns the quoting character. 210 * 211 * @return the quote character. 212 */ 213 public char getQuate () 214 { 215 return quate; 216 } 217 }