| 1 | /* |
| 2 | * Copyright 2006-2007 the original author or authors. |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package org.springframework.batch.item.xml; |
| 18 | |
| 19 | import java.io.BufferedWriter; |
| 20 | import java.io.File; |
| 21 | import java.io.FileOutputStream; |
| 22 | import java.io.IOException; |
| 23 | import java.io.OutputStreamWriter; |
| 24 | import java.io.UnsupportedEncodingException; |
| 25 | import java.io.Writer; |
| 26 | import java.nio.channels.Channels; |
| 27 | import java.nio.channels.FileChannel; |
| 28 | import java.util.List; |
| 29 | import java.util.Map; |
| 30 | |
| 31 | import javax.xml.stream.FactoryConfigurationError; |
| 32 | import javax.xml.stream.XMLEventFactory; |
| 33 | import javax.xml.stream.XMLEventWriter; |
| 34 | import javax.xml.stream.XMLOutputFactory; |
| 35 | import javax.xml.stream.XMLStreamException; |
| 36 | import javax.xml.transform.Result; |
| 37 | |
| 38 | import org.apache.commons.logging.Log; |
| 39 | import org.apache.commons.logging.LogFactory; |
| 40 | import org.springframework.batch.item.ExecutionContext; |
| 41 | import org.springframework.batch.item.ItemStreamException; |
| 42 | import org.springframework.batch.item.ItemWriter; |
| 43 | import org.springframework.batch.item.WriteFailedException; |
| 44 | import org.springframework.batch.item.file.ResourceAwareItemWriterItemStream; |
| 45 | import org.springframework.batch.item.util.ExecutionContextUserSupport; |
| 46 | import org.springframework.batch.item.util.FileUtils; |
| 47 | import org.springframework.batch.item.xml.stax.NoStartEndDocumentStreamWriter; |
| 48 | import org.springframework.batch.support.transaction.TransactionAwareBufferedWriter; |
| 49 | import org.springframework.beans.factory.InitializingBean; |
| 50 | import org.springframework.core.io.Resource; |
| 51 | import org.springframework.dao.DataAccessResourceFailureException; |
| 52 | import org.springframework.oxm.Marshaller; |
| 53 | import org.springframework.oxm.XmlMappingException; |
| 54 | import org.springframework.util.Assert; |
| 55 | import org.springframework.util.ClassUtils; |
| 56 | import org.springframework.util.CollectionUtils; |
| 57 | import org.springframework.util.StringUtils; |
| 58 | |
| 59 | /** |
| 60 | * An implementation of {@link ItemWriter} which uses StAX and |
| 61 | * {@link Marshaller} for serializing object to XML. |
| 62 | * |
| 63 | * This item writer also provides restart, statistics and transaction features |
| 64 | * by implementing corresponding interfaces. |
| 65 | * |
| 66 | * The implementation is *not* thread-safe. |
| 67 | * |
| 68 | * @author Peter Zozom |
| 69 | * @author Robert Kasanicky |
| 70 | * |
| 71 | */ |
| 72 | public class StaxEventItemWriter<T> extends ExecutionContextUserSupport implements |
| 73 | ResourceAwareItemWriterItemStream<T>, InitializingBean { |
| 74 | |
| 75 | private static final Log log = LogFactory.getLog(StaxEventItemWriter.class); |
| 76 | |
| 77 | // default encoding |
| 78 | private static final String DEFAULT_ENCODING = "UTF-8"; |
| 79 | |
| 80 | // default encoding |
| 81 | private static final String DEFAULT_XML_VERSION = "1.0"; |
| 82 | |
| 83 | // default root tag name |
| 84 | private static final String DEFAULT_ROOT_TAG_NAME = "root"; |
| 85 | |
| 86 | // restart data property name |
| 87 | private static final String RESTART_DATA_NAME = "position"; |
| 88 | |
| 89 | // restart data property name |
| 90 | private static final String WRITE_STATISTICS_NAME = "record.count"; |
| 91 | |
| 92 | // file system resource |
| 93 | private Resource resource; |
| 94 | |
| 95 | // xml marshaller |
| 96 | private Marshaller marshaller; |
| 97 | |
| 98 | // encoding to be used while reading from the resource |
| 99 | private String encoding = DEFAULT_ENCODING; |
| 100 | |
| 101 | // XML version |
| 102 | private String version = DEFAULT_XML_VERSION; |
| 103 | |
| 104 | // name of the root tag |
| 105 | private String rootTagName = DEFAULT_ROOT_TAG_NAME; |
| 106 | |
| 107 | // namespace prefix of the root tag |
| 108 | private String rootTagNamespacePrefix = ""; |
| 109 | |
| 110 | // namespace of the root tag |
| 111 | private String rootTagNamespace = ""; |
| 112 | |
| 113 | // root element attributes |
| 114 | private Map<String, String> rootElementAttributes = null; |
| 115 | |
| 116 | // TRUE means, that output file will be overwritten if exists - default is |
| 117 | // TRUE |
| 118 | private boolean overwriteOutput = true; |
| 119 | |
| 120 | // file channel |
| 121 | private FileChannel channel; |
| 122 | |
| 123 | // wrapper for XML event writer that swallows StartDocument and EndDocument |
| 124 | // events |
| 125 | private XMLEventWriter eventWriter; |
| 126 | |
| 127 | // XML event writer |
| 128 | private XMLEventWriter delegateEventWriter; |
| 129 | |
| 130 | // current count of processed records |
| 131 | private long currentRecordCount = 0; |
| 132 | |
| 133 | private boolean saveState = true; |
| 134 | |
| 135 | private StaxWriterCallback headerCallback; |
| 136 | |
| 137 | private StaxWriterCallback footerCallback; |
| 138 | |
| 139 | private Writer bufferedWriter; |
| 140 | |
| 141 | private boolean transactional = true; |
| 142 | |
| 143 | private boolean forceSync; |
| 144 | |
| 145 | public StaxEventItemWriter() { |
| 146 | setName(ClassUtils.getShortName(StaxEventItemWriter.class)); |
| 147 | } |
| 148 | |
| 149 | /** |
| 150 | * Set output file. |
| 151 | * |
| 152 | * @param resource the output file |
| 153 | */ |
| 154 | public void setResource(Resource resource) { |
| 155 | this.resource = resource; |
| 156 | } |
| 157 | |
| 158 | /** |
| 159 | * Set Object to XML marshaller. |
| 160 | * |
| 161 | * @param marshaller the Object to XML marshaller |
| 162 | */ |
| 163 | public void setMarshaller(Marshaller marshaller) { |
| 164 | this.marshaller = marshaller; |
| 165 | } |
| 166 | |
| 167 | /** |
| 168 | * headerCallback is called before writing any items. |
| 169 | */ |
| 170 | public void setHeaderCallback(StaxWriterCallback headerCallback) { |
| 171 | this.headerCallback = headerCallback; |
| 172 | } |
| 173 | |
| 174 | /** |
| 175 | * footerCallback is called after writing all items but before closing the |
| 176 | * file |
| 177 | */ |
| 178 | public void setFooterCallback(StaxWriterCallback footerCallback) { |
| 179 | this.footerCallback = footerCallback; |
| 180 | } |
| 181 | |
| 182 | /** |
| 183 | * Flag to indicate that writes should be deferred to the end of a |
| 184 | * transaction if present. Defaults to true. |
| 185 | * |
| 186 | * @param transactional the flag to set |
| 187 | */ |
| 188 | public void setTransactional(boolean transactional) { |
| 189 | this.transactional = transactional; |
| 190 | } |
| 191 | |
| 192 | /** |
| 193 | * Flag to indicate that changes should be force-synced to disk on flush. |
| 194 | * Defaults to false, which means that even with a local disk changes could |
| 195 | * be lost if the OS crashes in between a write and a cache flush. Setting |
| 196 | * to true may result in slower performance for usage patterns involving |
| 197 | * many frequent writes. |
| 198 | * |
| 199 | * @param forceSync the flag value to set |
| 200 | */ |
| 201 | public void setForceSync(boolean forceSync) { |
| 202 | this.forceSync = forceSync; |
| 203 | } |
| 204 | |
| 205 | /** |
| 206 | * Get used encoding. |
| 207 | * |
| 208 | * @return the encoding used |
| 209 | */ |
| 210 | public String getEncoding() { |
| 211 | return encoding; |
| 212 | } |
| 213 | |
| 214 | /** |
| 215 | * Set encoding to be used for output file. |
| 216 | * |
| 217 | * @param encoding the encoding to be used |
| 218 | */ |
| 219 | public void setEncoding(String encoding) { |
| 220 | this.encoding = encoding; |
| 221 | } |
| 222 | |
| 223 | /** |
| 224 | * Get XML version. |
| 225 | * |
| 226 | * @return the XML version used |
| 227 | */ |
| 228 | public String getVersion() { |
| 229 | return version; |
| 230 | } |
| 231 | |
| 232 | /** |
| 233 | * Set XML version to be used for output XML. |
| 234 | * |
| 235 | * @param version the XML version to be used |
| 236 | */ |
| 237 | public void setVersion(String version) { |
| 238 | this.version = version; |
| 239 | } |
| 240 | |
| 241 | /** |
| 242 | * Get the tag name of the root element. |
| 243 | * |
| 244 | * @return the root element tag name |
| 245 | */ |
| 246 | public String getRootTagName() { |
| 247 | return rootTagName; |
| 248 | } |
| 249 | |
| 250 | /** |
| 251 | * Set the tag name of the root element. If not set, default name is used |
| 252 | * ("root"). Namespace URI and prefix can also be set optionally using the |
| 253 | * notation: |
| 254 | * |
| 255 | * <pre> |
| 256 | * {uri}prefix:root |
| 257 | * </pre> |
| 258 | * |
| 259 | * The prefix is optional (defaults to empty), but if it is specified then |
| 260 | * the uri must be provided. In addition you might want to declare other |
| 261 | * namespaces using the {@link #setRootElementAttributes(Map) root |
| 262 | * attributes}. |
| 263 | * |
| 264 | * @param rootTagName the tag name to be used for the root element |
| 265 | */ |
| 266 | public void setRootTagName(String rootTagName) { |
| 267 | this.rootTagName = rootTagName; |
| 268 | } |
| 269 | |
| 270 | /** |
| 271 | * Get the namespace prefix of the root element. Empty by default. |
| 272 | * |
| 273 | * @return the rootTagNamespacePrefix |
| 274 | */ |
| 275 | public String getRootTagNamespacePrefix() { |
| 276 | return rootTagNamespacePrefix; |
| 277 | } |
| 278 | |
| 279 | /** |
| 280 | * Get the namespace of the root element. |
| 281 | * |
| 282 | * @return the rootTagNamespace |
| 283 | */ |
| 284 | public String getRootTagNamespace() { |
| 285 | return rootTagNamespace; |
| 286 | } |
| 287 | |
| 288 | /** |
| 289 | * Get attributes of the root element. |
| 290 | * |
| 291 | * @return attributes of the root element |
| 292 | */ |
| 293 | public Map<String, String> getRootElementAttributes() { |
| 294 | return rootElementAttributes; |
| 295 | } |
| 296 | |
| 297 | /** |
| 298 | * Set the root element attributes to be written. If any of the key names |
| 299 | * begin with "xmlns:" then they are treated as namespace declarations. |
| 300 | * |
| 301 | * @param rootElementAttributes attributes of the root element |
| 302 | */ |
| 303 | public void setRootElementAttributes(Map<String, String> rootElementAttributes) { |
| 304 | this.rootElementAttributes = rootElementAttributes; |
| 305 | } |
| 306 | |
| 307 | /** |
| 308 | * Set "overwrite" flag for the output file. Flag is ignored when output |
| 309 | * file processing is restarted. |
| 310 | * |
| 311 | * @param overwriteOutput |
| 312 | */ |
| 313 | public void setOverwriteOutput(boolean overwriteOutput) { |
| 314 | this.overwriteOutput = overwriteOutput; |
| 315 | } |
| 316 | |
| 317 | public void setSaveState(boolean saveState) { |
| 318 | this.saveState = saveState; |
| 319 | } |
| 320 | |
| 321 | /** |
| 322 | * @throws Exception |
| 323 | * @see org.springframework.beans.factory.InitializingBean#afterPropertiesSet() |
| 324 | */ |
| 325 | public void afterPropertiesSet() throws Exception { |
| 326 | Assert.notNull(marshaller); |
| 327 | if (rootTagName.contains("{")) { |
| 328 | rootTagNamespace = rootTagName.replaceAll("\\{(.*)\\}.*", "$1"); |
| 329 | rootTagName = rootTagName.replaceAll("\\{.*\\}(.*)", "$1"); |
| 330 | if (rootTagName.contains(":")) { |
| 331 | rootTagNamespacePrefix = rootTagName.replaceAll("(.*):.*", "$1"); |
| 332 | rootTagName = rootTagName.replaceAll(".*:(.*)", "$1"); |
| 333 | } |
| 334 | } |
| 335 | } |
| 336 | |
| 337 | /** |
| 338 | * Open the output source |
| 339 | * |
| 340 | * @see org.springframework.batch.item.ItemStream#open(ExecutionContext) |
| 341 | */ |
| 342 | public void open(ExecutionContext executionContext) { |
| 343 | |
| 344 | Assert.notNull(resource, "The resource must be set"); |
| 345 | |
| 346 | long startAtPosition = 0; |
| 347 | boolean restarted = false; |
| 348 | |
| 349 | // if restart data is provided, restart from provided offset |
| 350 | // otherwise start from beginning |
| 351 | if (executionContext.containsKey(getKey(RESTART_DATA_NAME))) { |
| 352 | startAtPosition = executionContext.getLong(getKey(RESTART_DATA_NAME)); |
| 353 | restarted = true; |
| 354 | } |
| 355 | |
| 356 | open(startAtPosition, restarted); |
| 357 | |
| 358 | if (startAtPosition == 0) { |
| 359 | try { |
| 360 | if (headerCallback != null) { |
| 361 | headerCallback.write(delegateEventWriter); |
| 362 | } |
| 363 | } |
| 364 | catch (IOException e) { |
| 365 | throw new ItemStreamException("Failed to write headerItems", e); |
| 366 | } |
| 367 | } |
| 368 | |
| 369 | } |
| 370 | |
| 371 | /** |
| 372 | * Helper method for opening output source at given file position |
| 373 | */ |
| 374 | private void open(long position, boolean restarted) { |
| 375 | |
| 376 | File file; |
| 377 | FileOutputStream os = null; |
| 378 | FileChannel fileChannel = null; |
| 379 | |
| 380 | try { |
| 381 | file = resource.getFile(); |
| 382 | FileUtils.setUpOutputFile(file, restarted, false, overwriteOutput); |
| 383 | Assert.state(resource.exists(), "Output resource must exist"); |
| 384 | os = new FileOutputStream(file, true); |
| 385 | fileChannel = os.getChannel(); |
| 386 | channel = os.getChannel(); |
| 387 | setPosition(position); |
| 388 | } |
| 389 | catch (IOException ioe) { |
| 390 | throw new DataAccessResourceFailureException("Unable to write to file resource: [" + resource + "]", ioe); |
| 391 | } |
| 392 | |
| 393 | XMLOutputFactory outputFactory = createXmlOutputFactory(); |
| 394 | |
| 395 | if (outputFactory.isPropertySupported("com.ctc.wstx.automaticEndElements")) { |
| 396 | // If the current XMLOutputFactory implementation is supplied by |
| 397 | // Woodstox >= 3.2.9 we want to disable its |
| 398 | // automatic end element feature (see: |
| 399 | // http://jira.codehaus.org/browse/WSTX-165) per |
| 400 | // http://jira.springframework.org/browse/BATCH-761). |
| 401 | outputFactory.setProperty("com.ctc.wstx.automaticEndElements", Boolean.FALSE); |
| 402 | } |
| 403 | if (outputFactory.isPropertySupported("com.ctc.wstx.outputValidateStructure")) { |
| 404 | // On restart we don't write the root element so we have to disable |
| 405 | // structural validation (see: |
| 406 | // http://jira.springframework.org/browse/BATCH-1681). |
| 407 | outputFactory.setProperty("com.ctc.wstx.outputValidateStructure", Boolean.FALSE); |
| 408 | } |
| 409 | |
| 410 | try { |
| 411 | final FileChannel channel = fileChannel; |
| 412 | Writer writer = new BufferedWriter(new OutputStreamWriter(os, encoding)) { |
| 413 | @Override |
| 414 | public void flush() throws IOException { |
| 415 | super.flush(); |
| 416 | if (forceSync) { |
| 417 | channel.force(false); |
| 418 | } |
| 419 | } |
| 420 | }; |
| 421 | if (transactional) { |
| 422 | bufferedWriter = new TransactionAwareBufferedWriter(writer, new Runnable() { |
| 423 | public void run() { |
| 424 | closeStream(); |
| 425 | } |
| 426 | }); |
| 427 | } |
| 428 | else { |
| 429 | bufferedWriter = writer; |
| 430 | } |
| 431 | delegateEventWriter = createXmlEventWriter(outputFactory, bufferedWriter); |
| 432 | eventWriter = new NoStartEndDocumentStreamWriter(delegateEventWriter); |
| 433 | if (!restarted) { |
| 434 | startDocument(delegateEventWriter); |
| 435 | } |
| 436 | } |
| 437 | catch (XMLStreamException xse) { |
| 438 | throw new DataAccessResourceFailureException("Unable to write to file resource: [" + resource + "]", xse); |
| 439 | } |
| 440 | catch (UnsupportedEncodingException e) { |
| 441 | throw new DataAccessResourceFailureException("Unable to write to file resource: [" + resource |
| 442 | + "] with encoding=[" + encoding + "]", e); |
| 443 | } |
| 444 | |
| 445 | } |
| 446 | |
| 447 | /** |
| 448 | * Subclasses can override to customize the writer. |
| 449 | * @param outputFactory |
| 450 | * @param writer |
| 451 | * @return an xml writer |
| 452 | * @throws XMLStreamException |
| 453 | */ |
| 454 | protected XMLEventWriter createXmlEventWriter(XMLOutputFactory outputFactory, Writer writer) |
| 455 | throws XMLStreamException { |
| 456 | return outputFactory.createXMLEventWriter(writer); |
| 457 | } |
| 458 | |
| 459 | /** |
| 460 | * Subclasses can override to customize the factory. |
| 461 | * @return a factory for the xml output |
| 462 | * @throws FactoryConfigurationError |
| 463 | */ |
| 464 | protected XMLOutputFactory createXmlOutputFactory() throws FactoryConfigurationError { |
| 465 | return XMLOutputFactory.newInstance(); |
| 466 | } |
| 467 | |
| 468 | /** |
| 469 | * Subclasses can override to customize the event factory. |
| 470 | * @return a factory for the xml events |
| 471 | * @throws FactoryConfigurationError |
| 472 | */ |
| 473 | protected XMLEventFactory createXmlEventFactory() throws FactoryConfigurationError { |
| 474 | XMLEventFactory factory = XMLEventFactory.newInstance(); |
| 475 | return factory; |
| 476 | } |
| 477 | |
| 478 | /** |
| 479 | * Subclasses can override to customize the stax result. |
| 480 | * @return a result for writing to |
| 481 | * @throws Exception |
| 482 | */ |
| 483 | protected Result createStaxResult() throws Exception { |
| 484 | return StaxUtils.getResult(eventWriter); |
| 485 | } |
| 486 | |
| 487 | /** |
| 488 | * Writes simple XML header containing: |
| 489 | * <ul> |
| 490 | * <li>xml declaration - defines encoding and XML version</li> |
| 491 | * <li>opening tag of the root element and its attributes</li> |
| 492 | * </ul> |
| 493 | * If this is not sufficient for you, simply override this method. Encoding, |
| 494 | * version and root tag name can be retrieved with corresponding getters. |
| 495 | * |
| 496 | * @param writer XML event writer |
| 497 | * @throws XMLStreamException |
| 498 | */ |
| 499 | protected void startDocument(XMLEventWriter writer) throws XMLStreamException { |
| 500 | |
| 501 | XMLEventFactory factory = createXmlEventFactory(); |
| 502 | |
| 503 | // write start document |
| 504 | writer.add(factory.createStartDocument(getEncoding(), getVersion())); |
| 505 | |
| 506 | // write root tag |
| 507 | writer.add(factory.createStartElement(getRootTagNamespacePrefix(), getRootTagNamespace(), getRootTagName())); |
| 508 | if (StringUtils.hasText(getRootTagNamespace())) { |
| 509 | if (StringUtils.hasText(getRootTagNamespacePrefix())) { |
| 510 | writer.add(factory.createNamespace(getRootTagNamespacePrefix(), getRootTagNamespace())); |
| 511 | } |
| 512 | else { |
| 513 | writer.add(factory.createNamespace(getRootTagNamespace())); |
| 514 | } |
| 515 | } |
| 516 | |
| 517 | // write root tag attributes |
| 518 | if (!CollectionUtils.isEmpty(getRootElementAttributes())) { |
| 519 | |
| 520 | for (Map.Entry<String, String> entry : getRootElementAttributes().entrySet()) { |
| 521 | String key = entry.getKey(); |
| 522 | if (key.startsWith("xmlns")) { |
| 523 | String prefix = ""; |
| 524 | if (key.contains(":")) { |
| 525 | prefix = key.substring(key.indexOf(":") + 1); |
| 526 | } |
| 527 | writer.add(factory.createNamespace(prefix, entry.getValue())); |
| 528 | } |
| 529 | else { |
| 530 | writer.add(factory.createAttribute(key, entry.getValue())); |
| 531 | } |
| 532 | } |
| 533 | |
| 534 | } |
| 535 | |
| 536 | /* |
| 537 | * This forces the flush to write the end of the root element and avoids |
| 538 | * an off-by-one error on restart. |
| 539 | */ |
| 540 | writer.add(factory.createIgnorableSpace("")); |
| 541 | writer.flush(); |
| 542 | |
| 543 | } |
| 544 | |
| 545 | /** |
| 546 | * Writes the EndDocument tag manually. |
| 547 | * |
| 548 | * @param writer XML event writer |
| 549 | * @throws XMLStreamException |
| 550 | */ |
| 551 | protected void endDocument(XMLEventWriter writer) throws XMLStreamException { |
| 552 | |
| 553 | // writer.writeEndDocument(); <- this doesn't work after restart |
| 554 | // we need to write end tag of the root element manually |
| 555 | |
| 556 | String nsPrefix = !StringUtils.hasText(getRootTagNamespacePrefix()) ? "" : getRootTagNamespacePrefix() + ":"; |
| 557 | try { |
| 558 | bufferedWriter.write("</" + nsPrefix + getRootTagName() + ">"); |
| 559 | } |
| 560 | catch (IOException ioe) { |
| 561 | throw new DataAccessResourceFailureException("Unable to close file resource: [" + resource + "]", ioe); |
| 562 | } |
| 563 | } |
| 564 | |
| 565 | /** |
| 566 | * Flush and close the output source. |
| 567 | * |
| 568 | * @see org.springframework.batch.item.ItemStream#close() |
| 569 | */ |
| 570 | public void close() { |
| 571 | |
| 572 | XMLEventFactory factory = createXmlEventFactory(); |
| 573 | try { |
| 574 | delegateEventWriter.add(factory.createCharacters("")); |
| 575 | } |
| 576 | catch (XMLStreamException e) { |
| 577 | log.error(e); |
| 578 | } |
| 579 | |
| 580 | try { |
| 581 | if (footerCallback != null) { |
| 582 | footerCallback.write(delegateEventWriter); |
| 583 | } |
| 584 | delegateEventWriter.flush(); |
| 585 | endDocument(delegateEventWriter); |
| 586 | } |
| 587 | catch (IOException e) { |
| 588 | throw new ItemStreamException("Failed to write footer items", e); |
| 589 | } |
| 590 | catch (XMLStreamException e) { |
| 591 | throw new ItemStreamException("Failed to write end document tag", e); |
| 592 | } |
| 593 | finally { |
| 594 | |
| 595 | try { |
| 596 | eventWriter.close(); |
| 597 | } |
| 598 | catch (XMLStreamException e) { |
| 599 | log.error("Unable to close file resource: [" + resource + "] " + e); |
| 600 | } |
| 601 | finally { |
| 602 | try { |
| 603 | bufferedWriter.close(); |
| 604 | } |
| 605 | catch (IOException e) { |
| 606 | log.error("Unable to close file resource: [" + resource + "] " + e); |
| 607 | } |
| 608 | finally { |
| 609 | if (!transactional) { |
| 610 | closeStream(); |
| 611 | } |
| 612 | } |
| 613 | } |
| 614 | } |
| 615 | } |
| 616 | |
| 617 | private void closeStream() { |
| 618 | try { |
| 619 | channel.close(); |
| 620 | } |
| 621 | catch (IOException ioe) { |
| 622 | log.error("Unable to close file resource: [" + resource + "] " + ioe); |
| 623 | } |
| 624 | } |
| 625 | |
| 626 | /** |
| 627 | * Write the value objects and flush them to the file. |
| 628 | * |
| 629 | * @param items the value object |
| 630 | * @throws IOException |
| 631 | * @throws XmlMappingException |
| 632 | */ |
| 633 | public void write(List<? extends T> items) throws XmlMappingException, Exception { |
| 634 | |
| 635 | currentRecordCount += items.size(); |
| 636 | |
| 637 | for (Object object : items) { |
| 638 | Assert.state(marshaller.supports(object.getClass()), |
| 639 | "Marshaller must support the class of the marshalled object"); |
| 640 | Result result = createStaxResult(); |
| 641 | marshaller.marshal(object, result); |
| 642 | } |
| 643 | try { |
| 644 | eventWriter.flush(); |
| 645 | } |
| 646 | catch (XMLStreamException e) { |
| 647 | throw new WriteFailedException("Failed to flush the events", e); |
| 648 | } |
| 649 | |
| 650 | } |
| 651 | |
| 652 | /** |
| 653 | * Get the restart data. |
| 654 | * |
| 655 | * @see org.springframework.batch.item.ItemStream#update(ExecutionContext) |
| 656 | */ |
| 657 | public void update(ExecutionContext executionContext) { |
| 658 | |
| 659 | if (saveState) { |
| 660 | Assert.notNull(executionContext, "ExecutionContext must not be null"); |
| 661 | executionContext.putLong(getKey(RESTART_DATA_NAME), getPosition()); |
| 662 | executionContext.putLong(getKey(WRITE_STATISTICS_NAME), currentRecordCount); |
| 663 | } |
| 664 | } |
| 665 | |
| 666 | /* |
| 667 | * Get the actual position in file channel. This method flushes any buffered |
| 668 | * data before position is read. |
| 669 | * |
| 670 | * @return byte offset in file channel |
| 671 | */ |
| 672 | private long getPosition() { |
| 673 | |
| 674 | long position; |
| 675 | |
| 676 | try { |
| 677 | eventWriter.flush(); |
| 678 | position = channel.position(); |
| 679 | if (bufferedWriter instanceof TransactionAwareBufferedWriter) { |
| 680 | position += ((TransactionAwareBufferedWriter) bufferedWriter).getBufferSize(); |
| 681 | } |
| 682 | } |
| 683 | catch (Exception e) { |
| 684 | throw new DataAccessResourceFailureException("Unable to write to file resource: [" + resource + "]", e); |
| 685 | } |
| 686 | |
| 687 | return position; |
| 688 | } |
| 689 | |
| 690 | /** |
| 691 | * Set the file channel position. |
| 692 | * |
| 693 | * @param newPosition new file channel position |
| 694 | */ |
| 695 | private void setPosition(long newPosition) { |
| 696 | |
| 697 | try { |
| 698 | channel.truncate(newPosition); |
| 699 | channel.position(newPosition); |
| 700 | } |
| 701 | catch (IOException e) { |
| 702 | throw new DataAccessResourceFailureException("Unable to write to file resource: [" + resource + "]", e); |
| 703 | } |
| 704 | |
| 705 | } |
| 706 | |
| 707 | } |