Read image from database
Hello, Can anyone tell me how do I read an image from a Blob field in the database? TX YuvalZ - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Read image from database
Zilberstein Yuval wrote: Hello, Can anyone tell me how do I read an image from a Blob field in the database? Not sure how this applies to taglibs, but you could look at: http://java.sun.com/j2se/1.4.2/docs/api/javax/imageio/ImageIO.html#read(java.io.InputStream) TX YuvalZ -- Kris Schneider mailto:[EMAIL PROTECTED] D.O.Tech http://www.dotech.com/ - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Read image from database
Zilberstein Yuval wrote:
Hello,
Can anyone tell me how do I read an image from a Blob field in the
database?
TX
YuvalZ
-
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I haven't put any of this into tags but
My experience is limited to our Oracle system.
I created two classes:
One wraps the Oracle implementation code and avoids the need to
import oracle.sql.BLOB;
import oracle.jdbc.OracleResultSet;
in places that are isolated from driver implementation details
Another converts the BLOB's to and from Image and byte[] so I can
display them.
For the web side, I adapted a servlet to display the image using this
fragment:
byte[] imageData = image.getImageBytes();
if ( imageData != null imageData.length 0){
response.setContentType(image/jpeg);
ServletOutputStream sos =
response.getOutputStream();
sos.write(imageData);
}
I only save a thumbnail in the database as a BLOB so the thumbnail is
the only image being returned in the response stream.
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Re: Read image from database
Don Albertson wrote:
Zilberstein Yuval wrote:
Hello,
Can anyone tell me how do I read an image from a Blob field in the
database?
TX
YuvalZ
-
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
I haven't put any of this into tags but
My experience is limited to our Oracle system. I created two classes:
One wraps the Oracle implementation code and avoids the need to
import oracle.sql.BLOB;
import oracle.jdbc.OracleResultSet;
in places that are isolated from driver implementation details
Another converts the BLOB's to and from Image and byte[] so I can
display them.
For the web side, I adapted a servlet to display the image using this
fragment:
byte[] imageData = image.getImageBytes();
if ( imageData != null imageData.length 0){
response.setContentType(image/jpeg);
ServletOutputStream sos =
response.getOutputStream();
sos.write(imageData);
}
I only save a thumbnail in the database as a BLOB so the thumbnail is
the only image being returned in the response stream.
If you're just serving the images out the database then there's certainly
no need to create an intermediate Image (like my first reply) - just grab
the byte[] and serve it with the proper content type. If the images are
unlikely to change, I'd recommend also setting response headers so that the
client knows it's OK to cache the images and can avoid making additional
requests for them.
--
Kris Schneider mailto:[EMAIL PROTECTED]
D.O.Tech http://www.dotech.com/
-
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Re: Read image from database
Kris Schneider wrote:
Don Albertson wrote:
Zilberstein Yuval wrote:
Hello,
Can anyone tell me how do I read an image from a Blob field in the
database?
TX
YuvalZ
-
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
I haven't put any of this into tags but
My experience is limited to our Oracle system. I created two classes:
One wraps the Oracle implementation code and avoids the need to
import oracle.sql.BLOB;
import oracle.jdbc.OracleResultSet;
in places that are isolated from driver implementation details
Another converts the BLOB's to and from Image and byte[] so I can
display them.
For the web side, I adapted a servlet to display the image using this
fragment:
byte[] imageData = image.getImageBytes();
if ( imageData != null imageData.length 0){
response.setContentType(image/jpeg);
ServletOutputStream sos =
response.getOutputStream();
sos.write(imageData);
}
I only save a thumbnail in the database as a BLOB so the thumbnail is
the only image being returned in the response stream.
If you're just serving the images out the database then there's
certainly no need to create an intermediate Image (like my first
reply) - just grab the byte[] and serve it with the proper content
type. If the images are unlikely to change, I'd recommend also setting
response headers so that the client knows it's OK to cache the images
and can avoid making additional requests for them.
The variable image isn't an Image, it's an instance of a class
that uses a BLOB and return it either as an Image or byte[]. In this
case, no Image is ever created. To the servlet, image is an interface.
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Re: Read image from database
Don Albertson wrote:
Kris Schneider wrote:
Don Albertson wrote:
Zilberstein Yuval wrote:
Hello,
Can anyone tell me how do I read an image from a Blob field in the
database?
TX
YuvalZ
-
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
I haven't put any of this into tags but
My experience is limited to our Oracle system. I created two classes:
One wraps the Oracle implementation code and avoids the need to
import oracle.sql.BLOB;
import oracle.jdbc.OracleResultSet;
in places that are isolated from driver implementation details
Another converts the BLOB's to and from Image and byte[] so I can
display them.
For the web side, I adapted a servlet to display the image using this
fragment:
byte[] imageData = image.getImageBytes();
if ( imageData != null imageData.length 0){
response.setContentType(image/jpeg);
ServletOutputStream sos =
response.getOutputStream();
sos.write(imageData);
}
I only save a thumbnail in the database as a BLOB so the thumbnail is
the only image being returned in the response stream.
If you're just serving the images out the database then there's
certainly no need to create an intermediate Image (like my first
reply) - just grab the byte[] and serve it with the proper content
type. If the images are unlikely to change, I'd recommend also setting
response headers so that the client knows it's OK to cache the images
and can avoid making additional requests for them.
The variable image isn't an Image, it's an instance of a class that
uses a BLOB and return it either as an Image or byte[]. In this case,
no Image is ever created. To the servlet, image is an interface.
I got that. My first response in this thread included an example of
creating a BufferedImage, which is what I was referring to.
--
Kris Schneider mailto:[EMAIL PROTECTED]
D.O.Tech http://www.dotech.com/
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Re: Read image from database
I think this should work :
InputStream input = null;
BufferedInputStream stream = null;
BLOB blob = null;
PrintWriter output = response.getWriter();
if (res.next()) {
blob = ( (OracleResultSet)
rs).getBLOB(COLUMN_NAME);
input = blob.getBinaryStream();
stream = new BufferedInputStream(input);
int length = -1;
while ((length = stream.read()) != -1) {
output.write(length);
}
}
/* flush the contents to the output */
output.flush();
On 4/11/07, Zilberstein Yuval [EMAIL PROTECTED] wrote:
Hello,
Can anyone tell me how do I read an image from a Blob field in the
database?
TX
YuvalZ
-
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
Re: Read image from database
Vikram Reddy wrote:
I think this should work :
InputStream input = null;
BufferedInputStream stream = null;
BLOB blob = null;
PrintWriter output = response.getWriter();
if (res.next()) {
blob = ( (OracleResultSet)
rs).getBLOB(COLUMN_NAME);
input = blob.getBinaryStream();
stream = new BufferedInputStream(input);
int length = -1;
while ((length = stream.read()) != -1) {
output.write(length);
}
}
/* flush the contents to the output */
output.flush();
That's pretty close to the approach that Don posted earlier. Couple of
comments about the code:
The standard ResultSet supports both getBlob(int i) and getBlob(String
colName). The standard Blob supports getBinaryStream(), as well as
getBytes(long pos, int length). I don't see a need to use Oracle-specific APIs.
Not to be picky, but why would you assign the result of
BufferedInputStream.read() to a var called length? It's just the next
byte of data.
Just noticed that you're also reading from an InputStream and writing to a
Writer. I'd recommend using ServletResponse.getOutputStream() instead.
On 4/11/07, Zilberstein Yuval [EMAIL PROTECTED] wrote:
Hello,
Can anyone tell me how do I read an image from a Blob field in the
database?
TX
YuvalZ
--
Kris Schneider mailto:[EMAIL PROTECTED]
D.O.Tech http://www.dotech.com/
-
To unsubscribe, e-mail: [EMAIL PROTECTED]
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