1/* 2 * Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 27package java.util.logging; 28 29import java.nio.charset.Charset; 30import java.time.Instant; 31import java.time.format.DateTimeFormatter; 32import java.util.*; 33 34/** 35 * Format a LogRecord into a standard XML format. 36 * <p> 37 * The DTD specification is provided as Appendix A to the 38 * Java Logging APIs specification. 39 * <p> 40 * The XMLFormatter can be used with arbitrary character encodings, 41 * but it is recommended that it normally be used with UTF-8. The 42 * character encoding can be set on the output Handler. 43 * 44 * @implSpec Since JDK 9, instances of {@linkplain LogRecord} contain 45 * an {@link LogRecord#getInstant() Instant} which can have nanoseconds below 46 * the millisecond resolution. 47 * The DTD specification has been updated to allow for an optional 48 * {@code <nanos>} element. By default, the XMLFormatter will compute the 49 * nanosecond adjustment below the millisecond resolution (using 50 * {@code LogRecord.getInstant().getNano() % 1000_000}) - and if this is not 0, 51 * this adjustment value will be printed in the new {@code <nanos>} element. 52 * The event instant can then be reconstructed using 53 * {@code Instant.ofEpochSecond(millis/1000L, (millis % 1000L) * 1000_000L + nanos)} 54 * where {@code millis} and {@code nanos} represent the numbers serialized in 55 * the {@code <millis>} and {@code <nanos>} elements, respectively. 56 * <br> 57 * The {@code <date>} element will now contain the whole instant as formatted 58 * by the {@link DateTimeFormatter#ISO_INSTANT DateTimeFormatter.ISO_INSTANT} 59 * formatter. 60 * <p> 61 * For compatibility with old parsers, XMLFormatters can 62 * be configured to revert to the old format by specifying a 63 * {@code <xml-formatter-fully-qualified-class-name>.useInstant = false} 64 * {@linkplain LogManager#getProperty(java.lang.String) property} in the 65 * logging configuration. When {@code useInstant} is {@code false}, the old 66 * formatting will be preserved. When {@code useInstant} is {@code true} 67 * (the default), the {@code <nanos>} element will be printed and the 68 * {@code <date>} element will contain the {@linkplain 69 * DateTimeFormatter#ISO_INSTANT formatted} instant. 70 * <p> 71 * For instance, in order to configure plain instances of XMLFormatter to omit 72 * the new {@code <nano>} element, 73 * {@code java.util.logging.XMLFormatter.useInstant = false} can be specified 74 * in the logging configuration. 75 * 76 * @since 1.4 77 */ 78 79public class XMLFormatter extends Formatter { 80 private final LogManager manager = LogManager.getLogManager(); 81 private final boolean useInstant; 82 83 /** 84 * Creates a new instance of XMLFormatter. 85 * 86 * @implSpec 87 * Since JDK 9, the XMLFormatter will print out the record {@linkplain 88 * LogRecord#getInstant() event time} as an Instant. This instant 89 * has the best resolution available on the system. The {@code <date>} 90 * element will contain the instant as formatted by the {@link 91 * DateTimeFormatter#ISO_INSTANT}. 92 * In addition, an optional {@code <nanos>} element containing a 93 * nanosecond adjustment will be printed if the instant contains some 94 * nanoseconds below the millisecond resolution. 95 * <p> 96 * This new behavior can be turned off, and the old formatting restored, 97 * by specifying a property in the {@linkplain 98 * LogManager#getProperty(java.lang.String) logging configuration}. 99 * If {@code LogManager.getLogManager().getProperty( 100 * this.getClass().getName()+".useInstant")} is {@code "false"} or 101 * {@code "0"}, the old formatting will be restored. 102 */ 103 public XMLFormatter() { 104 useInstant = (manager == null) 105 || manager.getBooleanProperty( 106 this.getClass().getName()+".useInstant", true); 107 } 108 109 // Append a two digit number. 110 private void a2(StringBuilder sb, int x) { 111 if (x < 10) { 112 sb.append('0'); 113 } 114 sb.append(x); 115 } 116 117 // Append the time and date in ISO 8601 format 118 private void appendISO8601(StringBuilder sb, long millis) { 119 GregorianCalendar cal = new GregorianCalendar(); 120 cal.setTimeInMillis(millis); 121 sb.append(cal.get(Calendar.YEAR)); 122 sb.append('-'); 123 a2(sb, cal.get(Calendar.MONTH) + 1); 124 sb.append('-'); 125 a2(sb, cal.get(Calendar.DAY_OF_MONTH)); 126 sb.append('T'); 127 a2(sb, cal.get(Calendar.HOUR_OF_DAY)); 128 sb.append(':'); 129 a2(sb, cal.get(Calendar.MINUTE)); 130 sb.append(':'); 131 a2(sb, cal.get(Calendar.SECOND)); 132 } 133 134 // Append to the given StringBuilder an escaped version of the 135 // given text string where XML special characters have been escaped. 136 // For a null string we append "<null>" 137 private void escape(StringBuilder sb, String text) { 138 if (text == null) { 139 text = "<null>"; 140 } 141 for (int i = 0; i < text.length(); i++) { 142 char ch = text.charAt(i); 143 if (ch == '<') { 144 sb.append("<"); 145 } else if (ch == '>') { 146 sb.append(">"); 147 } else if (ch == '&') { 148 sb.append("&"); 149 } else { 150 sb.append(ch); 151 } 152 } 153 } 154 155 /** 156 * Format the given message to XML. 157 * <p> 158 * This method can be overridden in a subclass. 159 * It is recommended to use the {@link Formatter#formatMessage} 160 * convenience method to localize and format the message field. 161 * 162 * @param record the log record to be formatted. 163 * @return a formatted log record 164 */ 165 @Override 166 public String format(LogRecord record) { 167 StringBuilder sb = new StringBuilder(500); 168 sb.append("<record>\n"); 169 170 final Instant instant = record.getInstant(); 171 172 sb.append(" <date>"); 173 if (useInstant) { 174 // If useInstant is true - we will print the instant in the 175 // date field, using the ISO_INSTANT formatter. 176 DateTimeFormatter.ISO_INSTANT.formatTo(instant, sb); 177 } else { 178 // If useInstant is false - we will keep the 'old' formating 179 appendISO8601(sb, instant.toEpochMilli()); 180 } 181 sb.append("</date>\n"); 182 183 sb.append(" <millis>"); 184 sb.append(instant.toEpochMilli()); 185 sb.append("</millis>\n"); 186 187 final int nanoAdjustment = instant.getNano() % 1000_000; 188 if (useInstant && nanoAdjustment != 0) { 189 sb.append(" <nanos>"); 190 sb.append(nanoAdjustment); 191 sb.append("</nanos>\n"); 192 } 193 194 sb.append(" <sequence>"); 195 sb.append(record.getSequenceNumber()); 196 sb.append("</sequence>\n"); 197 198 String name = record.getLoggerName(); 199 if (name != null) { 200 sb.append(" <logger>"); 201 escape(sb, name); 202 sb.append("</logger>\n"); 203 } 204 205 sb.append(" <level>"); 206 escape(sb, record.getLevel().toString()); 207 sb.append("</level>\n"); 208 209 if (record.getSourceClassName() != null) { 210 sb.append(" <class>"); 211 escape(sb, record.getSourceClassName()); 212 sb.append("</class>\n"); 213 } 214 215 if (record.getSourceMethodName() != null) { 216 sb.append(" <method>"); 217 escape(sb, record.getSourceMethodName()); 218 sb.append("</method>\n"); 219 } 220 221 sb.append(" <thread>"); 222 sb.append(record.getThreadID()); 223 sb.append("</thread>\n"); 224 225 if (record.getMessage() != null) { 226 // Format the message string and its accompanying parameters. 227 String message = formatMessage(record); 228 sb.append(" <message>"); 229 escape(sb, message); 230 sb.append("</message>"); 231 sb.append("\n"); 232 } 233 234 // If the message is being localized, output the key, resource 235 // bundle name, and params. 236 ResourceBundle bundle = record.getResourceBundle(); 237 try { 238 if (bundle != null && bundle.getString(record.getMessage()) != null) { 239 sb.append(" <key>"); 240 escape(sb, record.getMessage()); 241 sb.append("</key>\n"); 242 sb.append(" <catalog>"); 243 escape(sb, record.getResourceBundleName()); 244 sb.append("</catalog>\n"); 245 } 246 } catch (Exception ex) { 247 // The message is not in the catalog. Drop through. 248 } 249 250 Object parameters[] = record.getParameters(); 251 // Check to see if the parameter was not a messagetext format 252 // or was not null or empty 253 if (parameters != null && parameters.length != 0 254 && record.getMessage().indexOf('{') == -1 ) { 255 for (Object parameter : parameters) { 256 sb.append(" <param>"); 257 try { 258 escape(sb, parameter.toString()); 259 } catch (Exception ex) { 260 sb.append("???"); 261 } 262 sb.append("</param>\n"); 263 } 264 } 265 266 if (record.getThrown() != null) { 267 // Report on the state of the throwable. 268 Throwable th = record.getThrown(); 269 sb.append(" <exception>\n"); 270 sb.append(" <message>"); 271 escape(sb, th.toString()); 272 sb.append("</message>\n"); 273 StackTraceElement trace[] = th.getStackTrace(); 274 for (StackTraceElement frame : trace) { 275 sb.append(" <frame>\n"); 276 sb.append(" <class>"); 277 escape(sb, frame.getClassName()); 278 sb.append("</class>\n"); 279 sb.append(" <method>"); 280 escape(sb, frame.getMethodName()); 281 sb.append("</method>\n"); 282 // Check for a line number. 283 if (frame.getLineNumber() >= 0) { 284 sb.append(" <line>"); 285 sb.append(frame.getLineNumber()); 286 sb.append("</line>\n"); 287 } 288 sb.append(" </frame>\n"); 289 } 290 sb.append(" </exception>\n"); 291 } 292 293 sb.append("</record>\n"); 294 return sb.toString(); 295 } 296 297 /** 298 * Return the header string for a set of XML formatted records. 299 * 300 * @param h The target handler (can be null) 301 * @return a valid XML string 302 */ 303 @Override 304 public String getHead(Handler h) { 305 StringBuilder sb = new StringBuilder(); 306 String encoding; 307 sb.append("<?xml version=\"1.0\""); 308 309 if (h != null) { 310 encoding = h.getEncoding(); 311 } else { 312 encoding = null; 313 } 314 315 if (encoding == null) { 316 // Figure out the default encoding. 317 encoding = java.nio.charset.Charset.defaultCharset().name(); 318 } 319 // Try to map the encoding name to a canonical name. 320 try { 321 Charset cs = Charset.forName(encoding); 322 encoding = cs.name(); 323 } catch (Exception ex) { 324 // We hit problems finding a canonical name. 325 // Just use the raw encoding name. 326 } 327 328 sb.append(" encoding=\""); 329 sb.append(encoding); 330 sb.append("\""); 331 sb.append(" standalone=\"no\"?>\n"); 332 333 sb.append("<!DOCTYPE log SYSTEM \"logger.dtd\">\n"); 334 sb.append("<log>\n"); 335 return sb.toString(); 336 } 337 338 /** 339 * Return the tail string for a set of XML formatted records. 340 * 341 * @param h The target handler (can be null) 342 * @return a valid XML string 343 */ 344 @Override 345 public String getTail(Handler h) { 346 return "</log>\n"; 347 } 348} 349