How to use

loadAttachmentContent

method

in

com.xpn.xwiki.store.XWikiAttachmentStoreInterface

public void loadContent(XWikiContext context) throws XWikiException
{
  if (this.attachment_content == null) {
    try {
      context.getWiki().getAttachmentStore().loadAttachmentContent(this, context, true);
    } catch (Exception ex) {
      LOG.warn(String.format("Failed to load content for attachment [%s@%s]. "
        + "This attachment is broken, please consider re-uploading it. " + "Internal error: %s",
        getFilename(), (this.doc != null) ? this.doc.getFullName() : "<unknown>", ex.getMessage()));
    }
  }
}

@Override
public XWikiAttachment next()
{
  Object[] item = this.data.next();
  try {
    XWikiDocument doc =
      new XWikiDocument(HibernateAttachmentsReader.this.resolver.resolve(String.valueOf(item[0])));
    XWikiAttachment att = new XWikiAttachment(doc, String.valueOf(item[1]));
    HibernateAttachmentsReader.this.store.loadAttachmentContent(att,
      HibernateAttachmentsReader.this.context.get(), true);
    HibernateAttachmentsReader.this.archiveStore.loadArchive(att,
      HibernateAttachmentsReader.this.context.get(), true);
    HibernateAttachmentsReader.this.logger.debug("Loaded [{}] from the database", att.getReference());
    return att;
  } catch (Exception ex) {
    HibernateAttachmentsReader.this.logger.error("Failed to read attachment from the database store: {}",
      ex.getMessage(), ex);
  }
  return null;
}

@Override
public XWikiAttachment next()
{
  Object[] item = this.data.next();
  try {
    XWikiDocument doc =
      new XWikiDocument(HibernateAttachmentsReader.this.resolver.resolve(String.valueOf(item[0])));
    XWikiAttachment att = new XWikiAttachment(doc, String.valueOf(item[1]));
    HibernateAttachmentsReader.this.store.loadAttachmentContent(att,
      HibernateAttachmentsReader.this.context.get(), true);
    HibernateAttachmentsReader.this.archiveStore.loadArchive(att,
      HibernateAttachmentsReader.this.context.get(), true);
    HibernateAttachmentsReader.this.logger.debug("Loaded [{}] from the database", att.getReference());
    return att;
  } catch (Exception ex) {
    HibernateAttachmentsReader.this.logger.error("Failed to read attachment from the database store: {}",
      ex.getMessage(), ex);
  }
  return null;
}

  @Override
  public boolean storeEntity(XWikiAttachment entity)
  {
    if (entity == null) {
      return true;
    }
    XWikiAttachment existing =
      new XWikiAttachment(entity.getDoc(), entity.getFilename());
    try {
      this.store.loadAttachmentContent(existing, this.context.get(), false);
      // If loading succeeded, then the attachment already exists on the filesystem;
      // keep using the existing attachment version and discard the database one
      this.logger.debug("Skipped importing already existing attachment [{}]", entity.getReference());
      return true;
    } catch (XWikiException e) {
      // No such attachment on the filesystem, continue storing it
    }
    try {
      this.store.saveAttachmentContent(entity, false, this.context.get(), false);
      // The archive is also automatically stored by the call above, no need to explicitly store the archive
      this.logger.debug("Imported attachment [{}] into the filesystem store", entity.getReference());
      return true;
    } catch (XWikiException ex) {
      this.logger.error("Failed to store attachment into the filesystem store: {}", ex.getMessage(), ex);
      return false;
    }
  }
}

  @Override
  public boolean storeEntity(XWikiAttachment entity)
  {
    if (entity == null) {
      return true;
    }
    XWikiAttachment existing =
      new XWikiAttachment(entity.getDoc(), entity.getFilename());
    try {
      this.store.loadAttachmentContent(existing, this.context.get(), false);
      // If loading succeeded, then the attachment already exists on the filesystem;
      // keep using the existing attachment version and discard the database one
      this.logger.debug("Skipped importing already existing attachment [{}]", entity.getReference());
      return true;
    } catch (XWikiException e) {
      // No such attachment on the filesystem, continue storing it
    }
    try {
      this.store.saveAttachmentContent(entity, false, this.context.get(), false);
      // The archive is also automatically stored by the call above, no need to explicitly store the archive
      this.logger.debug("Imported attachment [{}] into the filesystem store", entity.getReference());
      return true;
    } catch (XWikiException ex) {
      this.logger.error("Failed to store attachment into the filesystem store: {}", ex.getMessage(), ex);
      return false;
    }
  }
}

public void loadAttachmentContent(XWikiAttachment attachment, XWikiContext context) throws XWikiException
{
  String database = context.getDatabase();
  try {
    // We might need to switch database to
    // get the translated content
    if (getDatabase() != null) {
      context.setDatabase(getDatabase());
    }
    context.getWiki().getAttachmentStore().loadAttachmentContent(attachment, context, true);
  } finally {
    if (database != null) {
      context.setDatabase(database);
    }
  }
}