5 Oracle Multimedia Java API Sample Application

5.2.1 Operations in the IMProductDialog Class

This class defines the following methods followed by a description of what each method does:

• The loadMedia( ) method to retrieve the media objects from the database. This method performs a SQL SELECT...FOR UPDATE statement on the PM.ONLINE_MEDIA table where the PRODUCT_ID column is a parameter marker. Then, this class uses the getORAData( ) and getORADataFactory( ) methods to get the media data objects from the result set.

• The displayMedia( ) method to display the media data, which in turn calls the corresponding media display methods displayImage( ), displayAudio( ), displayVideo( ), and displayDoc ( ).

• The displayImage( ) method calls the IMImagePanel.display( ) method to display the image data attributes, display the thumbnail image, and display the full sized image using a media player that supports this MIME type.

• The displayAudio( ) method calls the IMAudioPanel.display( ) method to display the audio data attributes and play the audio stream using a media player that supports this MIME type.

• The displayVideo( ) method calls the IMVideoPanel.display( ) method to display the video data attributes and play the video stream using a media player that supports this MIME type.

• The displayDoc( ) method calls the IMDocPanel.display( ) method to display the testimonial data attributes and play the testimonial data using a media player that supports this MIME type.

The following code example shows the loadMedia( ), displayMedia( ), displayImage( ), displayAudio( ), displayVideo( ), and displayDoc( ) methods, and highlights in bold the SQL query statements and areas in the code where Oracle Multimedia and other Oracle object types and methods are used.

  private void loadMedia() throws SQLException, IOException
  {
    String sQuery = 
      "select product_photo, product_thumbnail, product_audio, product_video, " + 
      "product_testimonials from pm.online_media where product_id = ? for update";

    OracleConnection conn = null;
    OracleResultSet rs = null;
    OraclePreparedStatement pstmt = null;
    boolean isInsertNeeded = false;
    byte[] ctx[] = new byte[1][64];

    try
    {
      conn = IMExample.getDBConnection();

      pstmt = (OraclePreparedStatement)conn.prepareStatement(sQuery);
      pstmt.setInt(1, m_iProdId);
      rs = (OracleResultSet)pstmt.executeQuery();
      if (rs.next() == true)
      {
        m_img = (OrdImage)rs.getORAData(1, OrdImage.getORADataFactory());
        m_imgThumb = (OrdImage)rs.getORAData(2, OrdImage.getORADataFactory());
        m_aud = (OrdAudio)rs.getORAData(3, OrdAudio.getORADataFactory());
        m_vid = (OrdVideo)rs.getORAData(4, OrdVideo.getORADataFactory());
        m_doc = (OrdDoc)rs.getORAData(5, OrdDoc.getORADataFactory());
      }

      displayMedia();

      rs.close();
      pstmt.close();
    }
    finally
    {
      IMUtil.cleanup(rs, pstmt);
    }
  }

  private void displayMedia() throws SQLException, IOException
  {
    displayImage();
    displayAudio();
    displayVideo();
    displayDoc();
  }

  /**   * Add the product photo panel.
   */
  private void displayImage() throws SQLException, IOException
  {
    m_jImgPanel = new IMImagePanel(this, 
        m_img, m_imgThumb, m_iProdId, m_colorFieldBg);
    m_jImgPanel.display();
    m_jImgPanel.getAccessibleContext().setAccessibleName
      ("Product photo panel");
    m_jImgPanel.getAccessibleContext().setAccessibleDescription
      ("Product photo panel with an image icon on the left, " + 
       "image attribute panel in the middle and image control" +
        "panel on the right.");

    m_jMediaPanel.add(m_jImgPanel);

    Component jImgFocus = m_jImgPanel.getFirstFocusComponent();
  }

  /**
   * Add the product audio panel.
   */
  private void displayAudio() throws SQLException, IOException
  {
    m_jAudPanel = new IMAudioPanel(this, m_aud, m_iProdId, m_colorFieldBg);
    m_jAudPanel.display();
    m_jAudPanel.getAccessibleContext().setAccessibleName
      ("Product audio panel");
    m_jAudPanel.getAccessibleContext().setAccessibleDescription(
        "Product audio panel with an audio icon at the left, " + 
        "audio attribute panel in the middle and audio control" +
        "panel at the right.");
    m_jMediaPanel.add(m_jAudPanel);
  }

  /**
   * Add the product video panel.
   */
  private void displayVideo() throws SQLException, IOException
  {
    m_jVidPanel = new IMVideoPanel(this, m_vid, m_iProdId, m_colorFieldBg); 
    m_jVidPanel.display();
    m_jVidPanel.getAccessibleContext().setAccessibleName
      ("Product audio panel");
    m_jVidPanel.getAccessibleContext().setAccessibleDescription(
        "Product audio panel with an video icon at the left, " + 
        "video attribute panel in the middle and video control" +
        "panel at the right.");
    m_jMediaPanel.add(m_jVidPanel);
  }

  /**
   * Add the product testimonials panel.
   */
  private void displayDoc() throws SQLException, IOException
  {
    m_jDocPanel = new IMDocPanel(this, m _doc, m_iProdId, m_colorFieldBg);
    m_jDocPanel.display();
    m_jDocPanel.getAccessibleContext().setAccessibleName
      ("Product testimonials panel");
    m_jDocPanel.getAccessibleContext().setAccessibleDescription(
        "Product testimonials panel with an document icon at the left, " + 
        "testimonials attribute panel in the middle and testimonials control" +
        "panel at the right.");
    m_jMediaPanel.add(m_jDocPanel);
  }

See the following sections, respectively, for code examples of the corresponding m_jXxxPanel.display( ) methods, where Xxx represents the particular media data type, Img, Aud, Vid, or Doc:

• Operations in the IMImagePanel Class

• Operations in the IMAudioPanel Class

• Operations in the IMVideoPanel Class

• Operations in the IMDocPanel Class

5.2.2 Operations in the IMImagePanel Class

This class displays the image panel, the product photo and its attributes, and the thumbnail image, and lists for reading and writing metadata. What follows is a more detailed description of each of the methods that are defined and what each method does:

• The display( ) method, which first calls the insertProperty( ) method, which calls the Oracle Multimedia image object type methods getMimeType( ), getHeight( ), getWidth( ), and getContentlength( ) to get the attributes of the image to display in a table, and lays out the user interface components for reading and writing image metadata.

• For supported formats, the class displays the product photo thumbnail image, which is generated by calling the IMUtil.generateThumbnail( )method to create the thumbnail image from the product photo.

• The addThumbnail( ) method to show the new thumbnail image.

• The changeThumbnail( ) method to change the thumbnail image.

• The saveToFile( ) method to save the photo to a file.

• The deleteMedia( ) method to delete the product photo image and its thumbnail image from the database by setting the image object type columns to empty using the OrdImage.init( ) method.

• The play( ) media method to show the image using a media player.

• The setMedia( ) method to set the photo and thumbnail object.

• The notExist( ) method checks whether the image data exists and returns true if the BLOB is empty or is not associated with an existing BFILE; otherwise, it returns false.

• The getDataInByteArray( ) method retrieves image data into a byte array by calling the Oracle Multimedia importData( ) method first for the BFILE and returns the results of calling the Oracle Multimedia getDataInByteArray( ) method.

• The refreshPanel( ) method refreshes the display when updating the photo image, attributes, and thumbnail image.

• The getFirstFocusComponent( ) method enforces the correct focus order.

• The emptyPanel( ) method clears the icon and attribute panel.

• The showMetadata( ) method to pop up a window for displaying metadata for the selected type.

• The writeMetadata( ) method to display the write metadata dialog.

The following code example includes the display( ), insertProperty( ), notExist( ), getDataInByteArray( ), and refreshPanel( ) methods, and highlights in bold any SQL query statements and areas in the code where Oracle Multimedia and other Oracle object types and methods are used:

  void display() throws IOException, SQLException
  {
    addControlPane();

    if (notExist(m_img))
    {
      // The image does not exist.
      m_hasMedia = false; 
      layoutEmpty(s_sNotExist);
    }
    else
    {
      m_hasMedia = true; 
      // If image exists, try to show the attributes.
      if (insertProperty())
      {
        // Show the thumbnail image.
        // If the thumbnail image does not exist, generate it first.
        if (m_imgThumb != null)
        {
          String sFormat = m_imgThumb.getFormat();

          if (notExist(m_imgThumb) ||
              ( !("JFIF".equalsIgnoreCase(sFormat)) &&
                !("GIFF".equalsIgnoreCase(sFormat))
              ))
          {
            m_imgThumb = IMUtil.generateThumbnail(m_iProdId, m_img, m_imgThumb);
          }

          byte[] thumbnail = getDataInByteArray(m_imgThumb);
          addThumbnail(thumbnail);
        }
        else
        {
          m_imgThumb = IMUtil.generateThumbnail(m_iProdId, m_img, m_imgThumb);
          byte[] thumbnail = getDataInByteArray(m_imgThumb);
          addThumbnail(thumbnail);
        }
      }
    }
  }
.
.
.
  boolean insertProperty() throws SQLException
  {
    boolean isFormatSupported = false;
    String sMimeType = m_img.getMimeType();

    if (sMimeType == null)
      isFormatSupported = IMUtil.setProperties(m_img);
    else
      isFormatSupported = true;

    if (!isFormatSupported)
    {
      layoutEmpty(s_sNotSupported);
    }
    else
    {
      Object[][] data = 
      {
        {"MIME Type",  m_img.getMimeType()},
        {"Height", new Integer(m_img.getHeight()).toString()},
        {"Width",  new Integer(m_img.getWidth()).toString()},
        {"Content Length", new Integer(m_img.getContentLength()).toString()}
      };

      .
      .
      .
    }

    return isFormatSupported;  }
.
.
.
  static boolean notExist(OrdImage img) throws SQLException, IOException
  {
    if (img == null)
      return true;
    else
    {
      if (img.isLocal() && (img.getDataInByteArray() == null))
        return true;
      else if (!img.isLocal() && (":///".equals(img.getSource())))
        return true;
      else
      {
        if (!img.isLocal())
        {
          BFILE bfile = img.getBFILE();
          if (!bfile.fileExists())
            return true;
          else 
            return false;
        }
        else
          return false;
      }
    }
  }
.
.
.
  static byte[] getDataInByteArray(OrdImage img) throws SQLException, IOException
  {
    if (notExist(img))
      return null;
    else
    {
      if (!img.isLocal())
      {
        byte[] ctx[] = new byte[1][4000];
        try
        {
          img.importData(ctx);
        }
        catch (SQLException e)
        {
          new IMMessage(IMConstants.ERROR, "MEDIA_SOURCE_ERR", e);
          return null;
        }
      }
      return img.getDataInByteArray();
    }
  }
.
.
.
  void refreshPanel(boolean isFormatSupported) throws SQLException, IOException
  {
    m_hasMedia = true;
    if (isFormatSupported)
    {
      if (m_jAttrTbl == null)
      {
        m_jAttrPane.remove(m_jEmpty);
        m_jIconPane.remove(m_jIcon);

        byte[] thumbnail = getDataInByteArray(m_imgThumb);
        addThumbnail(thumbnail);

        insertProperty();
      }
      else
      {
        byte[] thumbnail = getDataInByteArray(m_imgThumb);
        changThumbnail(thumbnail);

        m_jAttrTbl.setValueAt(m_img.getMimeType(), 0, 1);
        m_jAttrTbl.setValueAt(new Integer(m_img.getHeight()).toString(), 1, 1);
        m_jAttrTbl.setValueAt(new Integer(m_img.getWidth()).toString(), 2, 1);
        m_jAttrTbl.setValueAt(new Integer(m_img.getContentLength()).toString(),3, 1);
      }
    }
   .
   .
   .
  }

5.2.3 Operations in the IMGetMetadataDialog Class

This class shows a dialog to display detailed information for metadata in a product photograph. This class also defines the displayMetadata( ) method and describes what it does.

The displayMetadata( ) method retrieves metadata from the image by using the Oracle Multimedia OrdImage getMetadata( ) method, and then displays the metadata.

The following code example includes the displayMetadata( ) method, and highlights in bold any SQL query statements and areas in the code where Oracle Multimedia and other Oracle object types and methods are used:

  private void displayMetadata(String sMetaType) 
  {
    XMLDocument doc = null;
    try
    {
      //
      // Retrieves the metadata into an XMLType array
      //
      XMLType xmlList[] = m_img.getMetadata(sMetaType);
 
      if (xmlList.length == 1)
      {
        DOMParser parser = new DOMParser();
        parser.setValidationMode(XMLConstants.NONVALIDATING);
        parser.setPreserveWhitespace(false);
        parser.parse(new StringReader(XMLType.createXML(xmlList[0]).getStringVal()));
        doc = parser.getDocument();
      }
    }
    .
    .
    .
  }

5.2.4 Operations in the IMPutMetadataDialog Class

This class shows a dialog to write metadata into a product photograph. This class also defines the writeMetadata( ) method and describes what it does.

The writeMetadata( ) method writes XMP metadata into the image metadata by using the Oracle Multimedia OrdImage putMetadata( ) method.

The following code example includes the writeMetadata( ) method, and highlights in bold any SQL query statements and areas in the code where Oracle Multimedia and other Oracle object types and methods are used:

  void writeMetadata()
  {
    try
    {
      //
      // Let the StringBuffer to hold the XMP packet
      //
      StringBuffer sb = new StringBuffer(
          "<xmpMetadata xmlns=\"http://xmlns.oracle.com/ord/meta/xmp\" "
          + " xsi:schemaLocation=\"http://xmlns.oracle.com/ord/meta/xmp "
          + " http://xmlns.oracle.com/ord/meta/xmp\" "
          + " xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" > "
          + " <rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\"> "
          + " <rdf:Description about=\"\" xmlns:dc=\"http://purl.org/dc/elements/1.1/\"> "
          );
 
      String str = null;
      if ( (str=m_jTitleField.getText()) != null)
        sb.append("<dc:title>" + str + "</dc:title>");
      if ( (str=m_jCreatorField.getText()) !=null)
        sb.append("<dc:creator>" + str + "</dc:creator>");
      if ( (str=m_jDateField.getText()) !=null)
        sb.append("<dc:date>" + str + "</dc:date>");
      if ( (str=m_jDescriptionField.getText()) !=null)
        sb.append("<dc:description>" + str + "</dc:description>");
      if ( (str=m_jCopyrightField.getText()) !=null)
        sb.append("<dc:rights>" + str + "</dc:rights>");
 
      sb.append("</rdf:Description></rdf:RDF></xmpMetadata>");
 
      XMLType xmp = XMLType.createXML(IMExample.getDBConnection(), sb.toString(),
                "http://xmlns.oracle.com/ord/meta/xmp", true, true);
 
      //
      // Make sure the image data is local
      //
      if (!m_img.isLocal())
      {
        byte[] ctx[] = new byte[1][4000];
        m_img.importData(ctx);
      }
 
      //
      // Call Ordimage.putMetadata
      //
      m_img.putMetadata(xmp, "XMP", "utf-8");
 
      this.dispose();
    }
    .
    .
    .
  }

5.2.5 Operations in the IMVideoPanel Class

This class displays the video panel, the product video, and its attributes. This class is identical in structure and functions similarly to the IMImagePanel class. See Operations in the IMImagePanel Class for descriptions of methods.

The following code example includes the display( ), insertProperty( ), notExist( ), getDataInByteArray( ), and refreshPanel( ) methods, and highlights in bold any SQL query statements and areas in the code where Oracle Multimedia and other Oracle object types and methods are used:

  void display() throws IOException, SQLException
  {
    addControlPane();

    // Set the video icon.
    m_jIcon = new JLabel(new ImageIcon(IMExampleFrame.class.getResource("OrdVideo.gif")));
    m_jIcon.setLabelFor(m_jAttrPane);

      m_jIconPane.add(m_jIcon, BorderLayout.CENTER);

    if (notExist())
    {
      // The video does not exist.
      m_hasMedia = false; 
      layoutEmpty(s_sNotExist);
    }
    else
    {
      m_hasMedia = true; 
      // If the video exists, try to show the attributes.
      insertProperty();
    }
  }
.
.
.
  boolean insertProperty() throws SQLException
  {
    boolean isFormatSupported = false;
    String sMimeType = m_vid.getMimeType();

    if (sMimeType == null)
      isFormatSupported = IMUtil.setProperties(m_vid);
    else
      isFormatSupported = true;

    if (!isFormatSupported)
    {
      layoutEmpty(s_sNotSupported);
    }
    else
    {
      Object[][] data = 
      {
        {"MIME Type",  m_vid.getMimeType()},
        {"Height", new Integer(m_vid.getHeight()).toString()},
        {"Width",  new Integer(m_vid.getWidth()).toString()},
        {"Duration", new Integer(m_vid.getVideoDuration()).toString()},
        {"Content Length", new Integer(m_vid.getContentLength()).toString()}
      };
      .
      .
      .
    }

    return isFormatSupported;  }
.
.
.
  boolean notExist() throws SQLException, IOException
  {
    if (m_vid == null)
      return true;
    else
    {
      if (m_vid.isLocal() && (m_vid.getDataInByteArray() == null))
        return true;
      else if (!m_vid.isLocal() && (":///".equals(m_vid.getSource())))
        return true;
      else
      {
        if (!m_vid.isLocal())
        {
          BFILE bfile = m_vid.getBFILE();
          if (!bfile.fileExists())
            return true;
          else 
            return false;
        }
        else
          return false;
      }
    }
  }
.
.
.
  byte[] getDataInByteArray(OrdVideo vid) throws SQLException, IOException
  {
    if (!m_hasMedia)
      return null;
    else
    {
      if (!vid.isLocal())
      {
        byte[] ctx[] = new byte[1][4000];
        try
        {
          vid.importData(ctx);
        }
        catch (SQLException e)
        {
          new IMMessage(IMConstants.ERROR, "MEDIA_SOURCE_ERR", e);
          return null;
        }
      }
      return vid.getDataInByteArray();
    }
  }
.
.
.
  void refreshPanel(boolean isFormatSupported) throws SQLException, IOException
  {
    m_hasMedia = true;

    if (isFormatSupported)
    {
      if (m_jAttrTbl == null)
      {
        m_jAttrPane.remove(m_jEmpty);
        insertProperty();
      }
      else
      {
        m_jAttrTbl.setValueAt(m_vid.getMimeType(), 0, 1);
        m_jAttrTbl.setValueAt(new Integer(m_vid.getHeight()).toString(), 1, 1);
        m_jAttrTbl.setValueAt(new Integer(m_vid.getWidth()).toString(), 2, 1);
        m_jAttrTbl.setValueAt(new Integer(m_vid.getVideoDuration()).toString(), 3, 1);
        m_jAttrTbl.setValueAt(new Integer(m_vid.getContentLength()).toString(), 4, 1);
      }
    }
        .
        .
        .
  }

5.2.6 Operations in the IMAudioPanel Class

This class displays the audio panel, the product audio, and its attributes. This class is identical in structure and functions similarly to the IMImagePanel class. See Operations in the IMImagePanel Class for descriptions of methods.

The following code example includes the display( ), insertProperty( ), notExist( ), getDataInByteArray( ), and refreshPanel( ) methods, and highlights in bold any SQL query statements and areas in the code where Oracle Multimedia and other Oracle object types and methods are used:

  void display() throws IOException, SQLException
  {
    addControlPane();

    // Set the audio icon.
    m_jIcon = new JLabel(new ImageIcon(IMExampleFrame.class.getResource("OrdAudio.gif")));
    m_jIcon.setLabelFor(m_jAttrPane);

      m_jIconPane.add(m_jIcon, BorderLayout.CENTER);

    if (notExist())
    {
      // The audio does not exist.
      m_hasMedia = false; 
      layoutEmpty(s_sNotExist);
    }
    else
    {
      m_hasMedia = true;

      // If the audio exists, try to show the attributes.
      insertProperty();
    }
  }
.
.
.
  boolean insertProperty() throws SQLException
  {
    boolean isFormatSupported = false;
    String sMimeType = m_aud.getMimeType();

    if (sMimeType == null)
      isFormatSupported = IMUtil.setProperties(m_aud);
    else
      isFormatSupported = true;

    if (!isFormatSupported)
    {
      layoutEmpty(s_sNotSupported);
    }
    else
    {
      Object[][] data = 
      {
        {"MIME Type",  m_aud.getMimeType()},
        {"Duration", new Integer(m_aud.getAudioDuration()).toString()},
        {"Content Length", new Integer(m_aud.getContentLength()).toString()}
      };

      .
      .
      .
    }

    return isFormatSupported;
  }
.
.
.
  boolean notExist() throws SQLException, IOException
  {
    if (m_aud == null)
      return true;
    else
    {
      if (m_aud.isLocal() && (m_aud.getDataInByteArray() == null))
        return true;
      else if (!m_aud.isLocal() && (":///".equals(m_aud.getSource())))
        return true;
      else
      {
        if (!m_aud.isLocal())
        {
          BFILE bfile = m_aud.getBFILE();
          if (!bfile.fileExists())
            return true;
          else 
            return false;
        }
        else
          return false;
      }
    }
  }
.
.
.
  byte[] getDataInByteArray(OrdAudio aud) throws SQLException, IOException
  {
    if (!m_hasMedia)
      return null;
    else
    {
      if (!aud.isLocal())
      {
        byte[] ctx[] = new byte[1][4000];
        try
        {
          aud.importData(ctx);
        }
        catch (SQLException e)
        {
          new IMMessage(IMConstants.ERROR, "MEDIA_SOURCE_ERR", e);
          return null;
        }
      }
      return aud.getDataInByteArray();
    }
  }
.
.
.
  void refreshPanel(boolean isFormatSupported) throws SQLException, IOException
  {
    m_hasMedia = true;
    if (isFormatSupported)
    {
      if (m_jAttrTbl == null)
      {
        m_jAttrPane.remove(m_jEmpty);
        insertProperty();
      }
      else
      {
        m_jAttrTbl.setValueAt(m_aud.getMimeType(), 0, 1);
        m_jAttrTbl.setValueAt(new Integer(m_aud.getAudioDuration()).toString(), 1, 1);
        m_jAttrTbl.setValueAt(new Integer(m_aud.getContentLength()).toString(), 2, 1);
      }
    }
    .
    .
    .
  }

5.2.7 Operations in the IMDocPanel Class

This class displays the doc panel, the product testimonials, and its attributes. This class is identical in structure and functions similarly to the IMImagePanel class. See Operations in the IMImagePanel Class for descriptions of methods.

The following code example includes the display( ), insertProperty( ), notExist( ), getDataInByteArray( ), and refreshPanel( ) methods, and highlights in bold any SQL query statements and areas in the code where Oracle Multimedia and other Oracle object types and methods are used:

  void display() throws IOException, SQLException
  {
    addControlPane();

    // Set the icon.
    m_jIcon = new JLabel(new ImageIcon(
          IMExampleFrame.class.getResource("OrdDoc.gif")
          ));
    m_jIcon.setLabelFor(m_jAttrPane);
      m_jIconPane.add(m_jIcon, BorderLayout.CENTER);

    if (notExist())
    {
      // The doc does not exist.
      m_hasMedia = false; 
      layoutEmpty(s_sNotExist);
    }
    else
    {
      // If the doc exists, show the attribute table.
      m_hasMedia = true; 
      insertProperty();
    }
  }
.
.
.
  boolean insertProperty() throws SQLException
  {
    boolean isFormatSupported = false;
    String sMimeType = m_doc.getMimeType();

    if (sMimeType == null)
      isFormatSupported = IMUtil.setProperties(m_doc);
    else
      isFormatSupported = true;

    if (!isFormatSupported)
    {
      layoutEmpty(s_sNotSupported);
    }
    else
    {
      Object[][] data = 
      {
        {"MIME Type",  m_doc.getMimeType()},
        {"Content Length", new Integer(m_doc.getContentLength()).toString()}
      };

     .
     .
     .
    }

    return isFormatSupported;
  }
.
.
.
  boolean notExist() throws SQLException, IOException
  {
    if (m_doc == null)
      return true;
    else
    {
      if (m_doc.isLocal() && (m_doc.getDataInByteArray() == null))
        return true;
      else if (!m_doc.isLocal() && (":///".equals(m_doc.getSource())))
        return true;
      else
      {
        if (!m_doc.isLocal())
        {
          BFILE bfile = m_doc.getBFILE();
          if (!bfile.fileExists())
            return true;
          else 
            return false;
        }
        else
          return false;
      }
    }
  }
.
.
.
  byte[] getDataInByteArray(OrdDoc doc) throws SQLException, IOException
  {
    if (!m_hasMedia)
      return null;
    else
    {
      if (!doc.isLocal())
      {
        byte[] ctx[] = new byte[1][4000];
        try
        {
          doc.importData(ctx, false);
        }
        catch (SQLException e)
        {
          new IMMessage(IMConstants.ERROR, "MEDIA_SOURCE_ERR", e);
          return null;
        }
      }
      return doc.getDataInByteArray();
    }
  }
.
.
.
  void refreshPanel(boolean isFormatSupported) throws SQLException, IOException
  {
    m_hasMedia = true;
    if (isFormatSupported)
    {
      if (m_jAttrTbl == null)
      {
        m_jAttrPane.remove(m_jEmpty);
        insertProperty();
      }
      else
      {
        m_jAttrTbl.setValueAt(m_doc.getMimeType(), 0, 1);
        m_jAttrTbl.setValueAt(new Integer(m_doc.getContentLength()).toString(), 1, 1);
      }
    }
.
.
.
  }

5.2.8 Operations in the IMLoadFile Class

This class loads a media stream from a file to a database for each of the media object types. First, it checks whether this PRODUCT_ID column exists in the PM.ONLINE_MEDIA table and if not, it inserts a new row into the table. Then, it creates and initializes a new media object for each media object type, updates the media data, that is, loads it into the database if it is not already stored there, and finally, sets the media attributes for each media data object.

In this class, the IMFileLoad( ) method calls the initFileChooser( ) method, then the initFileChooser( ) method calls the loadNewMedia( ) method, which does the row insertion and initializing of the media object type columns, and then calls the updateMedia( ) method to update the media and to set the media attributes.

The following code example includes the loadNewMedia( ) and UpdateMedia( ) methods, and highlights in bold any SQL query statements and areas in the code where Oracle Multimedia and other Oracle object types and methods are used as previously described:

  private void loadNewMedia() 
    throws SQLException, FileNotFoundException, SecurityException, IOException
  {
    boolean isInsertNeeded = false;
    String sQuery = null;
    OracleConnection conn = null;
    OracleResultSet rs = null;
    OraclePreparedStatement pstmt = null;

    try
    {
      conn = IMExample.getDBConnection();

      if (m_obj == null)
      {
        // First, check whether or not this product exists in the 
        // pm.online_media table. If it exists, isInsertNeeded is set to false;
        // or else, isInsertNeeded is set to true.
        sQuery = new String(
            "select product_id from pm.online_media where product_id = ?");
        pstmt = (OraclePreparedStatement) conn.prepareStatement(sQuery);
        pstmt.setInt(1, m_iProdId);
        rs = (OracleResultSet)pstmt.executeQuery();
        if (rs.next() == false)
          isInsertNeeded = true;
        else
          isInsertNeeded = false;
        rs.close();
        pstmt.close();

        if (isInsertNeeded)
        {
          // If this product is not in the pm.online_media table, 
          // insert a row in pm.online_media for this product,
          // and initialize the media object at the same time.
          sQuery = new String(
              "insert into pm.online_media (product_id, product_photo, " + 
              "product_photo_signature, product_thumbnail, product_video, " + 
              "product_audio, product_text, product_testimonials) values (" + 
              "?, ORDSYS.ORDImage.init(), ORDSYS.ORDImageSignature.init(), " +
              "ORDSYS.ORDImage.init(),  ORDSYS.ORDVideo.init(), " +
              "ORDSYS.ORDAudio.init(), null, ORDSYS.ORDDoc.init())");

          pstmt = (OraclePreparedStatement) conn.prepareCall(sQuery);
          pstmt.setInt(1, m_iProdId);
          pstmt.execute();
          pstmt.close();
        }
      }

    if (!isInsertNeeded)
    {
      // Create a new media object.
      switch (m_iTypeIdentifier)
      {
        case IMG_TYPE:
          sQuery = new String(
              "update pm.online_media set " + m_sColName + 
              " = ORDSYS.ORDImage.init() where product_id = ?");
          break;
        case AUD_TYPE:
          sQuery = new String(
              "update pm.online_media set " + m_sColName +
              " = ORDSYS.ORDAudio.init() where product_id = ?");
          break;
        case VID_TYPE:
          sQuery = new String(
              "update pm.online_media set " + m_sColName + 
              " = ORDSYS.ORDVideo.init() where product_id = ?");
          break;
        case DOC_TYPE:
          sQuery = new String(
              "update pm.online_media set " + m_sColName +  
              " = ORDSYS.ORDDoc.init() where product_id = ?"); 
          break;
        default:
          new IMMessage(IMConstants.ERROR, "UNKNOWN_TYPE");
          break;
      }

      pstmt = (OraclePreparedStatement) conn.prepareCall(sQuery);
      pstmt.setInt(1, m_iProdId);
      pstmt.execute();
      pstmt.close();
    }

      // At this point, there is a row in the online_media table
      // for this product and the desired media object is initialized.
      // In the following, we update the media object pointer and 
      // acquire the right to modify it by selecting again from the
      // database.
      //
      sQuery = new String(
          "select " + m_sColName + 
          " from pm.online_media where product_id = ? for update");
      pstmt = (OraclePreparedStatement) conn.prepareStatement(sQuery);
      pstmt.setInt(1, m_iProdId);
      rs = (OracleResultSet)pstmt.executeQuery();
      if (rs.next() == false)
        throw new SQLException();
      else
      {
        switch (m_iTypeIdentifier)
        {
          case IMG_TYPE:
            m_img = (OrdImage)rs.getORAData(1, OrdImage.getORADataFactory());
            break;
          case AUD_TYPE:
            m_aud = (OrdAudio)rs.getORAData(1, OrdAudio.getORADataFactory());
            break;
          case VID_TYPE:
            m_vid = (OrdVideo)rs.getORAData(1, OrdVideo.getORADataFactory());
            break;
          case DOC_TYPE:
            m_doc = (OrdDoc)rs.getORAData(1, OrdDoc.getORADataFactory());
            break;
          default:
            new IMMessage(IMConstants.ERROR, "UNKNOWN_TYPE");
            break;
        }

        // Update the media object.
        updateMedia();
      }

      rs.close();
      pstmt.close();
    }
    finally
    {
      IMUtil.cleanup(rs, pstmt);
    }
  }

  /**
   * Update the media and also set the media properties.
   */
  private void updateMedia()
    throws SQLException, FileNotFoundException, SecurityException, IOException
  {
    String sQuery = null;
    OracleConnection conn = null;
    byte[] ctx[] = new byte[1][64];
    OraclePreparedStatement pstmt = null;

    boolean isFormatSupported = false;

    try
    {
      conn = IMExample.getDBConnection();
      sQuery = new String(
          "update pm.online_media set " + m_sColName + 
          " = ? where product_id = ?");
      pstmt = (OraclePreparedStatement) conn.prepareCall(sQuery);
      pstmt.setInt(2, m_iProdId);

      switch (m_iTypeIdentifier)
      {
        case IMG_TYPE:
          m_img.loadDataFromFile(m_jFileChooser.getText());
          isFormatSupported = IMUtil.setProperties(m_img);
          m_img.setLocal();
          pstmt.setORAData(1, m_img);
          break;
        case AUD_TYPE:
          m_aud.loadDataFromFile(m_jFileChooser.getText());
          isFormatSupported = IMUtil.setProperties(m_aud);
          m_aud.setLocal();
          pstmt.setORAData(1, m_aud);

          // We need to update the media pointer for display,
          // because the input media pointer may be null.
          ((IMAudioPanel)m_parent).setMedia(m_aud);
          ((IMAudioPanel)m_parent).refreshPanel(isFormatSupported);
          break;
        case VID_TYPE:
          m_vid.loadDataFromFile(m_jFileChooser.getText());
          isFormatSupported = IMUtil.setProperties(m_vid);
          m_vid.setLocal();
          pstmt.setORAData(1, m_vid);

          ((IMVideoPanel)m_parent).setMedia(m_vid);
          ((IMVideoPanel)m_parent).refreshPanel(isFormatSupported);
          break;
        case DOC_TYPE:
          m_doc.loadDataFromFile(m_jFileChooser.getText());
          isFormatSupported = IMUtil.setProperties(m_doc);
          m_doc.setLocal();
          pstmt.setORAData(1, m_doc);

          ((IMDocPanel)m_parent).setMedia(m_doc);
          ((IMDocPanel)m_parent).refreshPanel(isFormatSupported);
          break;
        default:
          new IMMessage(IMConstants.ERROR, "UNKNOWN_TYPE");
          break;
      }

      pstmt.execute();
      pstmt.close();

      // Update the thumbnail image.
      if (m_iTypeIdentifier == IMG_TYPE)
      {
        if (isFormatSupported)
          m_imgThumb = IMUtil.generateThumbnail(m_iProdId, m_img, m_imgThumb);

        ((IMImagePanel)m_parent).setMedia(m_img, m_imgThumb);
        ((IMImagePanel)m_parent).refreshPanel(isFormatSupported);
      }
    }
    finally
    {
      IMUtil.cleanup(pstmt);
    }
  }

5.2.9 Operations in the IMUtil Class

This class contains common utilities, such as a generateThumbnail( ) static method, wrapper methods for the setProperties( ) methods for each media object type to separate the exceptions caused by unrecognizable formats, and finally, several cleanup methods.

The following code example includes the generateThumbnail( ) method, and highlights in bold any SQL query statements and areas in the code where Oracle Multimedia and other Oracle object types and methods are used:

static OrdImage generateThumbnail(int iProdId, OrdImage img, OrdImage imgThumb)
  throws SQLException
  {
    String sQuery = null;
    OracleConnection conn = null;
    OracleResultSet rs = null;
    OraclePreparedStatement pstmt = null;

    try
    {
      conn = IMExample.getDBConnection();

      if (imgThumb == null)
      {
        // The thumbnail media pointer is not initialized.
        // Initialize it first.
        sQuery = new String(
            "update pm.online_media set product_thumbnail = " + 
            "ORDSYS.ORDImage.init() where product_id = ?");
        pstmt = (OraclePreparedStatement) conn.prepareCall(sQuery);
        pstmt.setInt(1, iProdId);
        pstmt.execute();
        pstmt.close();

        // Acquire the new pointer and the permission to update.
        sQuery = new String("select product_thumbnail from pm.online_media " +
            "where product_id = ? for update");
        pstmt = (OraclePreparedStatement) conn.prepareStatement(sQuery);
        pstmt.setInt(1, iProdId);
        rs = (OracleResultSet)pstmt.executeQuery();
        if (rs.next() == false)
          throw new SQLException();
        else
          imgThumb = (OrdImage)rs.getORAData(1, OrdImage.getORADataFactory());

        rs.close();
        pstmt.close();
      }

      // Generate the thumbnail image.
      img.processCopy("maxScale=64 64, fileFormat=GIFF", imgThumb);

      // Update the thumbnail image in the database.
      sQuery = new String(
          "update pm.online_media set product_thumbnail = ? where product_id = ?");
      pstmt = (OraclePreparedStatement) conn.prepareCall(sQuery);
      pstmt.setORAData(1, imgThumb);
      pstmt.setInt(2, iProdId);
      pstmt.execute();
      pstmt.close();

      return imgThumb;
    }
    finally
    {
      IMUtil.cleanup(rs, pstmt);
    }
  }