gt:         if (file.getLength() <= 0) {
context: /*
   * This library is part of OpenCms -
   * the Open Source Content Management System
   *
   * Copyright (c) Alkacon Software GmbH & Co. KG (http://www.alkacon.com)
   *
   * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
   * Lesser General Public License for more details.
   *
   * For further information about Alkacon Software GmbH & Co. KG, please see the
   * company website: http://www.alkacon.com
   *
   * For further information about OpenCms, please see the
   * project website: http://www.opencms.org
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   */
  
  package org.opencms.search.documents;
  
  import org.opencms.file.CmsFile;
  import org.opencms.file.CmsObject;
  import org.opencms.file.CmsResource;
  import org.opencms.main.CmsException;
  import org.opencms.main.CmsLog;
  import org.opencms.search.I_CmsSearchDocument;
  import org.opencms.search.I_CmsSearchIndex;
  import org.opencms.search.extractors.I_CmsExtractionResult;
  
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  
  import org.apache.commons.logging.Log;
  
  /**
   * Base document factory class for a VFS <code>{@link org.opencms.file.CmsResource}</code>,
   * just requires a specialized implementation of
   * <code>{@link I_CmsDocumentFactory#extractContent(CmsObject, CmsResource, I_CmsSearchIndex)}</code>
   * for text extraction from the binary document content.<p>
   *
   * @since 6.0.0
   */
  public abstract class A_CmsVfsDocument implements I_CmsDocumentFactory {
  
      /**
       * Generic type name used as default for all types that are globally unconfigured.
       * Note that any special xml content is already configured if xmlcontent is configured.
       */
      public static final String DEFAULT_ALL_UNCONFIGURED_TYPES = "__unconfigured__";
      /** Generic type name used as default for all types. */
      public static final String DEFAULT_ALL_TYPES = "__all__";
      /** The log object for this class. */
      private static final Log LOG = CmsLog.getLog(A_CmsVfsDocument.class);
  
      /** Name of the document type. */
      protected String m_name;
  
      /** The cache used for storing extracted documents. */
      private CmsExtractionResultCache m_cache;
  
      /**
       * Creates a new instance of this lucene document factory.<p>
       *
       * @param name name of the documenttype
       */
      public A_CmsVfsDocument(String name) {
  
          m_name = name;
      }
  
      /**
       * Creates a document factory lookup key for the given resource type name / MIME type configuration.<p>
       *
       * If the given <code>mimeType</code> is <code>null</code>, this indicates that the key should
       * match all VFS resource of the given resource type regardless of the MIME type.<p>
       *
       * @param type the resource type name to use
       * @param mimeType the MIME type to use
       *
       * @return a document factory lookup key for the given resource id / MIME type configuration
       */
      public static String getDocumentKey(String type, String mimeType) {
  
          StringBuffer result = new StringBuffer(16);
          result.append(I_CmsSearchDocument.VFS_DOCUMENT_KEY_PREFIX);
          result.append('_');
          result.append(type);
          if (mimeType != null) {
              result.append(':');
              result.append(mimeType);
          }
          return result.toString();
      }
  
      /**
       * Generates a new lucene document instance from contents of the given resource for the provided index.<p>
       *
       * @see org.opencms.search.documents.I_CmsDocumentFactory#createDocument(CmsObject, CmsResource, I_CmsSearchIndex)
       */
      public I_CmsSearchDocument createDocument(CmsObject cms, CmsResource resource, I_CmsSearchIndex index)
      throws CmsException {
  
          // extract the content from the resource
          I_CmsExtractionResult content = null;
  
          if (index.isExtractingContent()) {
              // do full text content extraction only if required
  
              // check if caching is enabled for this document type
              CmsExtractionResultCache cache = getCache();
              String cacheName = null;
              if ((cache != null) && (resource.getSiblingCount() > 1)) {
                  // hard drive based caching only makes sense for resources that have siblings,
                  // because the index will also store the content as a blob
                  cacheName = cache.getCacheName(
                      resource,
                      isLocaleDependend() ? index.getLocaleForResource(cms, resource, null) : null,
                      getName());
                  content = cache.getCacheObject(cacheName);
              }
  
              if (content == null) {
                  // extraction result has not been found in the cache
                  // use the currently indexed content, if it is still up to date.
                  content = index.getContentIfUnchanged(resource);
              }
  
              if (content == null) {
                  // extraction result has not been attached to the resource
                  try {
                      content = extractContent(cms, resource, index);
                      if (LOG.isDebugEnabled()) {
                          LOG.debug("Extracting content for '" + resource.getRootPath() + "' successful.");
                      }
                      if ((cache != null) && (resource.getSiblingCount() > 1)) {
                          // save extracted content to the cache
                          cache.saveCacheObject(cacheName, content);
                      }
                  } catch (CmsIndexNoContentException e) {
                      // there was no content found for the resource
                      LOG.info(
                          Messages.get().getBundle().key(Messages.ERR_TEXT_EXTRACTION_1, resource.getRootPath())
                              + " "
                              + e.getMessage());
                  } catch (Throwable e) {
                      // text extraction failed for document - continue indexing meta information only
                      LOG.error(
                          Messages.get().getBundle().key(Messages.ERR_TEXT_EXTRACTION_1, resource.getRootPath()),
                          e);
                  }
              }
          }
  
          // create the Lucene document according to the index field configuration
          return index.getFieldConfiguration().createDocument(cms, resource, index, content);
      }
  
      /**
       * @see org.opencms.search.documents.I_CmsDocumentFactory#getCache()
       */
      public CmsExtractionResultCache getCache() {
  
          return m_cache;
      }
  
      /**
       * @see org.opencms.search.documents.I_CmsDocumentFactory#getDocumentKeys(java.util.List, java.util.List)
       */
      public List<String> getDocumentKeys(List<String> resourceTypes, List<String> mimeTypes) throws CmsException {
  
          List<String> keys = new ArrayList<String>();
  
          try {
              for (Iterator<String> i = resourceTypes.iterator(); i.hasNext();) {
  
                  String typeName = i.next();
                  if (typeName.equals("*")) {
                      typeName = DEFAULT_ALL_UNCONFIGURED_TYPES;
                  }
                  if (typeName.equals("**")) {
                      typeName = DEFAULT_ALL_TYPES;
                  }
                  for (Iterator<String> j = mimeTypes.iterator(); j.hasNext();) {
                      keys.add(getDocumentKey(typeName, j.next()));
                  }
                  if (mimeTypes.isEmpty()) {
                      keys.add(getDocumentKey(typeName, null));
                  }
              }
          } catch (Exception exc) {
              throw new CmsException(Messages.get().container(Messages.ERR_CREATE_DOC_KEY_0), exc);
          }
  
          return keys;
      }
  
      /**
       * @see org.opencms.search.documents.I_CmsDocumentFactory#getName()
       */
      public String getName() {
  
          return m_name;
      }
  
      /**
       * @see org.opencms.search.documents.I_CmsDocumentFactory#setCache(org.opencms.search.documents.CmsExtractionResultCache)
       */
      public void setCache(CmsExtractionResultCache cache) {
  
          m_cache = cache;
      }
  
      /**
       * Logs content extraction for the specified resource and index.<p>
       *
       * @param resource the resource to log content extraction for
       * @param index the search index to log content extraction for
       */
      protected void logContentExtraction(CmsResource resource, I_CmsSearchIndex index) {
  
          if (LOG.isDebugEnabled()) {
              LOG.debug(
                  Messages.get().getBundle().key(
                      Messages.LOG_EXTRACT_CONTENT_2,
                      resource.getRootPath(),
                      index.getName()));
          }
      }
  
      /**
       * Upgrades the given resource to a {@link CmsFile} with content.<p>
       *
       * @param cms the current users OpenCms context
       * @param resource the resource to upgrade
       *
       * @return the given resource upgraded to a {@link CmsFile} with content
       *
       * @throws CmsException if the resource could not be read
       * @throws CmsIndexNoContentException if the resource has no content
       */
      protected CmsFile readFile(CmsObject cms, CmsResource resource) throws CmsException, CmsIndexNoContentException {
  
          CmsFile file = cms.readFile(resource);
  