Oracle interMedia Java Classes for Servlets and JSP API Reference: Class OrdHttpResponseHandler

The OrdHttpResponseHandler class facilitates the retrieval of multimedia data from an Oracle database and its delivery to a browser or other HTTP client from a Java Servlet.

The following example illustrates how to use the OrdHttpResponseHandler class to retrieve an image from a database and deliver it to a browser:

If you wish to retrieve from an OrdDoc object a text-based document with a charset other than ISO-8859-1 (also called Latin-1) and deliver that document to a browser, then your application must specify the charset name in the HTTP Content-Type header.

If the charset specification is included in the MIME type attribute in the OrdDoc object, then your application need only call the sendDoc() method to retrieve the document and deliver it to the browser. For example, for an HTML page written in Japanese, the MIME type might be stored in the OrdDoc object as:

    text/html; charset=Shift_JIS

In this case, calling sendDoc() will send the appropriate Content-Type header allowing the browser to display the page correctly.

However, if the MIME type in the OrdDoc object does not include the charset specification, then you must call one of the sendResponse methods and specify the MIME type explicitly. For example, if the MIME type for an HTML page written in Japanese is stored in the OrdDoc object as:

    text/html

and the charset name is specified in a separate column, then the application must append the charset specification to the MIME type before calling a sendResponse method. For example:

  OraclePreparedStatement stmt =
      (OraclePreparedStatement)conn.prepareStatement(
          "select doc, charset from documents where id = ?" );
  stmt.setString( 1, request.getParameter("id") );
  OracleResultSet rset = (OracleResultSet)stmt.executeQuery();
  if ( rset.next() )
  {
      OrdDoc doc = (OrdDoc)rset.getORAData( 1, OrdDoc.getORADataFactory() );
      String charset = rset.getString( 2 );
      String mimeType = doc.getMimeType() + "; charset=" + charset;
      OrdHttpResponseHandler handler =
                      new OrdHttpResponseHandler( request, response );
      handler.sendResponse( mimeType, doc.getContentLength(),
                            doc.getContent(), doc.getUpdateTime() );
  }
  else
  {
      response.setStatus( response.SC_NOT_FOUND );
  }
  rset.close();
  stmt.close();

Field Summary
`static int`	`DEFAULT_BUFFER_SIZE` The OrdHttpResponseHandler class uses a default buffer size of 32768 to retrieve LOB data from the database and deliver it to the client.

Constructor Summary
`OrdHttpResponseHandler()` Creates an OrdHttpResponseHandler object to handle the response to a multimedia retrieval request.
`OrdHttpResponseHandler(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response)` Creates an OrdHttpResponseHandler object to handle the response to a multimedia retrieval request and specifies the HttpServletRequest and HttpServletResponse objects for the response handler.

Method Summary
`void`	`sendAudio(oracle.ord.im.OrdAudio media)` Retrieves an audio clip from an OrdAudio object and delivers it to the browser.
`void`	`sendDoc(oracle.ord.im.OrdDoc media)` Retrieves media data from an OrdDoc object and delivers it to the browser.
`void`	`sendImage(oracle.ord.im.OrdImage media)` Retrieves an image from an OrdImage object and delivers it to the browser.
`void`	`sendResponse()` Retrieves contents from the interMedia object (OrdImage, OrdAudio, OrdVideo or OrdDoc) from the database and delivers it to the browser.
`void`	`sendResponse(java.lang.String contentType, int length, oracle.sql.BFILE bfile, java.sql.Timestamp lastModified)` Builds an HTTP response header, then retrieves the contents of the BFILE from the database and delivers it to the browser.
`void`	`sendResponse(java.lang.String contentType, int length, oracle.sql.BLOB blob, java.sql.Timestamp lastModified)` Builds an HTTP response header, then retrieves the contents of the BLOB from the database and delivers it to the browser.
`void`	`sendResponse(java.lang.String contentType, int length, java.io.InputStream in, java.sql.Timestamp lastModified)` Builds an HTTP response header, then retrieves the contents from the InputStream and delivers it to the browser.
`void`	`sendResponseBody(int length, oracle.sql.BFILE bfile)` Retrieves the contents of a BFILE from the database and delivers it as the response body to the client.
`void`	`sendResponseBody(int length, oracle.sql.BLOB blob)` Retrieves the contents of a BLOB from the database and delivers it as the response body to the client.
`void`	`sendResponseBody(int length, java.io.InputStream in)` Retrieves the contents from the InputStream and delivers it to the client.
`void`	`sendVideo(oracle.ord.im.OrdVideo media)` Retrieves a video clip from an OrdVideo object and delivers it to the browser.
`void`	`setBufferSize(int bufferSize)` Sets the buffer size for LOB read and response write operations.
`void`	`setEncodeHtml(boolean doEncode)` Enable encoding of special characters from the response stream with text/html mimetype.
`void`	`setHeader(java.lang.String name, int value)` Set the response header with Int value.
`void`	`setHeader(java.lang.String name, long date)` Set the response header with Date value.
`void`	`setHeader(java.lang.String name, java.lang.String value)` Set the response header with String value.
`void`	`setMedia(oracle.ord.im.OrdAudio media)` Set the media object to be delivered.
`void`	`setMedia(oracle.ord.im.OrdDoc media)` Set the media object to be delivered.
`void`	`setMedia(oracle.ord.im.OrdImage media)` Set the media object to be delivered.
`void`	`setMedia(oracle.ord.im.OrdVideo media)` Set the media object to be delivered.
`void`	`setServletRequest(javax.servlet.http.HttpServletRequest request)` Specifies the HttpServletRequest object for this response handler.
`void`	`setServletResponse(javax.servlet.http.HttpServletResponse response)` Specifies the HttpServletResponse object for this response handler.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_BUFFER_SIZE

public static final int DEFAULT_BUFFER_SIZE

The OrdHttpResponseHandler class uses a default buffer size of 32768 to retrieve LOB data from the database and deliver it to the client. This value can be overridden using the setBufferSize() method.

Constructor Detail

OrdHttpResponseHandler

public OrdHttpResponseHandler()

Creates an OrdHttpResponseHandler object to handle the response to a multimedia retrieval request. The application must subsequently specify the HttpServletResponse object by calling setServletResponse(), and can optionally specify the HttpServletRequest object by calling setServletRequest().

OrdHttpResponseHandler

public OrdHttpResponseHandler(javax.servlet.http.HttpServletRequest request,
                              javax.servlet.http.HttpServletResponse response)

Creates an OrdHttpResponseHandler object to handle the response to a multimedia retrieval request and specifies the HttpServletRequest and HttpServletResponse objects for the response handler.

Parameters:: request - an object of type HttpServletRequest.; response - an object of type HttpServletResponse.

Method Detail

setServletRequest

public void setServletRequest(javax.servlet.http.HttpServletRequest request)

Specifies the HttpServletRequest object for this response handler. You must call this method if you did not specify the HttpServletRequest object in the constructor and you want to call any of the send methods other than the sendResponseBody methods. You do not need to call this method if you call only the sendResponseBody methods.

Parameters:: request - an object of type HttpServletRequest.

setServletResponse

public void setServletResponse(javax.servlet.http.HttpServletResponse response)

Specifies the HttpServletResponse object for this response handler. You must call this method before calling any of the send methods if you did not specify the HttpServletResponse object in the constructor

Parameters:: response - an object of type HttpServletResponse.

sendImage

public void sendImage(oracle.ord.im.OrdImage media)
               throws javax.servlet.ServletException,
                      java.sql.SQLException,
                      java.io.IOException

Retrieves an image from an OrdImage object and delivers it to the browser. This method supports browser content caching by supporting the If-Modified-Since and Last-Modified headers.

Parameters:: image - an object of type oracle.ord.im.OrdImage.
Throws:: java.lang.IllegalStateException - if HttpServletRequest or HttpServletResponse has not been specified; OrdHttpResponseException - if the source type is not recognized.; javax.servlet.ServletException - if an error occurs accessing the binary output stream.; java.sql.SQLException - if an error occurs obtaining an InputStream to read the image data.; java.io.IOException - if an error occurs reading the image data.

sendAudio

public void sendAudio(oracle.ord.im.OrdAudio media)
               throws javax.servlet.ServletException,
                      java.sql.SQLException,
                      java.io.IOException

Retrieves an audio clip from an OrdAudio object and delivers it to the browser. This method supports browser content caching by supporting the If-Modified-Since and Last-Modified headers.

Parameters:: audio - an object of type oracle.ord.im.OrdAudio.
Throws:: java.lang.IllegalStateException - if HttpServletRequest or HttpServletResponse has not been specified; OrdHttpResponseException - if the source type is not recognized.; javax.servlet.ServletException - if an error occurs accessing the binary output stream.; java.sql.SQLException - if an error occurs obtaining an InputStream to read the audio data.; java.io.IOException - if an error occurs reading the audio data.

sendVideo

public void sendVideo(oracle.ord.im.OrdVideo media)
               throws javax.servlet.ServletException,
                      java.sql.SQLException,
                      java.io.IOException

Retrieves a video clip from an OrdVideo object and delivers it to the browser. This method supports browser content caching by supporting the If-Modified-Since and Last-Modified headers.

Parameters:: video - an object of type oracle.ord.im.OrdVideo.
Throws:: java.lang.IllegalStateException - if HttpServletRequest or HttpServletResponse has not been specified; OrdHttpResponseException - if the source type is not recognized.; javax.servlet.ServletException - if an error occurs accessing the binary output stream.; java.sql.SQLException - if an error occurs obtaining an InputStream to read the video data.; java.io.IOException - if an error occurs reading the video data.

sendDoc

public void sendDoc(oracle.ord.im.OrdDoc media)
             throws javax.servlet.ServletException,
                    java.sql.SQLException,
                    java.io.IOException

Retrieves media data from an OrdDoc object and delivers it to the browser. This method supports browser content caching by supporting the If-Modified-Since and Last-Modified headers.

Parameters:: doc - an object of type oracle.ord.im.OrdDoc.
Throws:: java.lang.IllegalStateException - if HttpServletRequest or HttpServletResponse has not been specified; OrdHttpResponseException - if the source type is not recognized.; javax.servlet.ServletException - if an error occurs accessing the binary output stream.; java.sql.SQLException - if an error occurs obtaining an InputStream to read the media data.; java.io.IOException - if an error occurs reading the media data.

sendResponse

public void sendResponse(java.lang.String contentType,
                         int length,
                         oracle.sql.BLOB blob,
                         java.sql.Timestamp lastModified)
                  throws javax.servlet.ServletException,
                         java.sql.SQLException,
                         java.io.IOException

Builds an HTTP response header, then retrieves the contents of the BLOB from the database and delivers it to the browser. This method supports browser content caching by supporting the If-Modified-Since and Last-Modified headers.

Parameters:: contentType - a String that specifies the content's MIME type.; length - an int that specifies the length of the data.; blob - an oracle.sql.BLOB from which the multimedia data is retrieved.; lastModified - a java.sql.Timestamp that specifies the date/time when the data was last modified, or null if no last modified date/time is available.
Throws:: java.lang.IllegalStateException - if HttpServletRequest or HttpServletResponse has not been specified.; java.lang.IllegalArgumentException - if the length is negative.; javax.servlet.ServletException - if an error occurs accessing the binary output stream.; java.sql.SQLException - if an error occurs obtaining an InputStream to read the multimedia data.; java.io.IOException - if an error occurs reading the multimedia data.

sendResponse

public void sendResponse(java.lang.String contentType,
                         int length,
                         oracle.sql.BFILE bfile,
                         java.sql.Timestamp lastModified)
                  throws javax.servlet.ServletException,
                         java.sql.SQLException,
                         java.io.IOException

Builds an HTTP response header, then retrieves the contents of the BFILE from the database and delivers it to the browser. This method supports browser content caching by supporting the If-Modified-Since and Last-Modified headers.

Parameters:: contentType - a String that specifies the content's MIME type.; length - an int that specifies the length of the data.; bfile - an oracle.sql.BFILE from which the multimedia data is retrieved.; lastModified - a java.sql.Timestamp that specifies the date/time when the data was last modified, or null if no last modified date/time is available.
Throws:: java.lang.IllegalStateException - if HttpServletRequest or HttpServletResponse has not been specified.; java.lang.IllegalArgumentException - if the length is negative.; javax.servlet.ServletException - if an error occurs accessing the binary output stream.; java.sql.SQLException - if an error occurs obtaining an InputStream to read the multimedia data.; java.io.IOException - if an error occurs reading the multimedia data.

sendResponse

public void sendResponse(java.lang.String contentType,
                         int length,
                         java.io.InputStream in,
                         java.sql.Timestamp lastModified)
                  throws javax.servlet.ServletException,
                         java.io.IOException

Builds an HTTP response header, then retrieves the contents from the InputStream and delivers it to the browser. This method supports browser content caching by supporting the If-Modified-Since and Last-Modified headers.

Parameters:: contentType - a String that specifies the content's MIME type.; length - an int that specifies the length of the data.; in - an InputStream from which the multimedia data is retrieved.; lastModified - a java.sql.Timestamp that specifies the date/time when the data was last modified, or null if no last modified date/time is available.
Throws:: java.lang.IllegalStateException - if HttpServletRequest or HttpServletResponse has not been specified.; java.lang.IllegalArgumentException - if the length is negative.; javax.servlet.ServletException - if an error occurs accessing the binary output stream.; java.io.IOException - if an error occurs reading the multimedia data.

sendResponseBody

public void sendResponseBody(int length,
                             oracle.sql.BLOB blob)
                      throws javax.servlet.ServletException,
                             java.sql.SQLException,
                             java.io.IOException

Retrieves the contents of a BLOB from the database and delivers it as the response body to the client. The caller is responsible for building the HTTP header.

Parameters:: length - an int that specifies the length of the data.; blob - an oracle.sql.BLOB from which the content is retrieved.
Throws:: java.lang.IllegalStateException - if HttpServletRequest has not been specified.; java.lang.IllegalArgumentException - if the length is negative.; javax.servlet.ServletException - if an error occurs accessing the binary output stream.; java.sql.SQLException - if an error occurs obtaining an InputStream to read the multimedia data.; java.io.IOException - if an error occurs reading the multimedia data.

sendResponseBody

public void sendResponseBody(int length,
                             oracle.sql.BFILE bfile)
                      throws javax.servlet.ServletException,
                             java.sql.SQLException,
                             java.io.IOException

Retrieves the contents of a BFILE from the database and delivers it as the response body to the client. The caller is responsible for building the HTTP header.

Parameters:: length - an int that specifies the length of the data.; bfile - an oracle.sql.BFILE from which the content is retrieved.
Throws:: java.lang.IllegalStateException - if HttpServletRequest has not been specified.; java.lang.IllegalArgumentException - if the length is negative.; javax.servlet.ServletException - if an error occurs accessing the binary output stream.; java.sql.SQLException - if an error occurs obtaining an InputStream to read the multimedia data.; java.io.IOException - if an error occurs reading the multimedia data.

sendResponseBody

public void sendResponseBody(int length,
                             java.io.InputStream in)
                      throws javax.servlet.ServletException,
                             java.io.IOException

Retrieves the contents from the InputStream and delivers it to the client. The caller is responsible for building the HTTP header.

Parameters:: length - content length.; in - an InputStream from which the multimedia data is retrieved.
Throws:: java.lang.IllegalStateException - if HttpServletRequest has not been specified.; java.lang.IllegalArgumentException - if the length is negative.; javax.servlet.ServletException - if an error occurs accessing the binary output stream.; java.io.IOException - if an error occurs reading the multimedia data.

setBufferSize

public void setBufferSize(int bufferSize)
                   throws java.lang.IllegalArgumentException

Sets the buffer size for LOB read and response write operations.

Parameters:: bufferSize - an int that specifies the buffer size.
Throws:: java.lang.IllegalArgumentException - if the buffer size is negative or zero.

setMedia

public void setMedia(oracle.ord.im.OrdImage media)

Set the media object to be delivered. If the media object has already been set, the new object overwrites the previous one. This method has to be called before sendResponse() method in order to deliver the data in the response body.

Parameters:: media - an object of type oracle.ord.im.OrdImage.

setMedia

public void setMedia(oracle.ord.im.OrdAudio media)

Parameters:: media - an object of type oracle.ord.im.OrdAudio.

setMedia

public void setMedia(oracle.ord.im.OrdVideo media)

Parameters:: media - an object of type oracle.ord.im.OrdVideo.

setMedia

public void setMedia(oracle.ord.im.OrdDoc media)

Parameters:: media - an object of type oracle.ord.im.OrdDoc.

setHeader

public void setHeader(java.lang.String name,
                      java.lang.String value)

Set the response header with String value. If the header has already been set, the new value overwrites the previous value.

Parameters:: name - the name of the header.; value - the value of the header.

setHeader

public void setHeader(java.lang.String name,
                      long date)

Set the response header with Date value. If the header has already been set, the new value overwrites the previous value.

Parameters:: name - the name of the header.; date - the date value of the header.

setHeader

public void setHeader(java.lang.String name,
                      int value)

Set the response header with Int value. If the header has already been set, the new value overwrites the previous value.

Parameters:: name - the name of the header.; value - the int value of the header.

sendResponse

public void sendResponse()
                  throws javax.servlet.ServletException,
                         java.sql.SQLException,
                         java.io.IOException

Retrieves contents from the interMedia object (OrdImage, OrdAudio, OrdVideo or OrdDoc) from the database and delivers it to the browser. The media object that is to be delivered is determined by the setMedia() method. This method supports browser content caching by supporting the If-Modified-Since and Last-Modified headers.

Throws:: java.lang.IllegalStateException - if HttpServletRequest or HttpServletResponse has not been specified; OrdHttpResponseException - if the source type is not recognized.; javax.servlet.ServletException - if an error occurs accessing the binary output stream.; java.sql.SQLException - if an error occurs obtaining an InputStream to read the media data.; java.io.IOException - if an error occurs reading the media data.

setEncodeHtml

public void setEncodeHtml(boolean doEncode)

Enable encoding of special characters from the response stream with text/html mimetype. When enabled, the special characters (! " % & ' ( ) ; < >) are replaced with HTML numeric encoding during the delivery in order to prevent cross-site scripting. By default, html encoding is disabled.

Parameters:: doEncode - a boolean that specifies whether to encode the response output stream.

Overview

Class

Tree

Deprecated

Index

Help

Oracle interMedia Java Classes for Servlets and JSP API Reference
10g Release 1 (10.1)
Part No. B12249-01

PREV CLASS NEXT CLASS

FRAMES NO FRAMES

SUMMARY: INNER | FIELD | CONSTR | METHOD

DETAIL: FIELD | CONSTR | METHOD

oracle.ord.im Class OrdHttpResponseHandler

DEFAULT_BUFFER_SIZE

OrdHttpResponseHandler

OrdHttpResponseHandler

setServletRequest

setServletResponse

sendImage

sendAudio

sendVideo

sendDoc

sendResponse

sendResponse

sendResponse

sendResponseBody

sendResponseBody

sendResponseBody

setBufferSize

setMedia

setMedia

setMedia

setMedia

setHeader

setHeader

setHeader

sendResponse

setEncodeHtml

oracle.ord.im
Class OrdHttpResponseHandler