Toplink 9.0.4.6, Batching and CLOBS

Question

Hello,
New to this forum, new to Java and very new to Toplink. So, please forgive me if I ask a stupid question or two.
I have written a java program whose purpose is to migrate data from one schema to another. For the most part, it works well, except for a few issues.
The legacy table contains a number of varchar(4000) fields (Oracle 9i), and the equivelant fields in the new schema (Oracle 10g) are CLOB fields. I ran my migration code a few times, and found it a bit too slow for my liking. In an effort to speed it up, I did the following:
1. Turned on batching in the connection to the database
2. Refactored java code to allow for batching commits to the database
After doing this, migration code runs a lot faster, but, now I have an issue with writing from the Varchar(4000) fields to CLOB fields. To be specific, about half the records that are migrated wind up with either null values in the corresponding CLOB fields, or a series of spaces - but not the text that should be there. To reiterate, in some cases the data seems to migrate fine, in others, well, not so fine or not at all.
My question is this: is this a known issue? If so, how do I fix it? Before I started batching my commits, things seemed to be going well.
Not sure what else to include here, other than the following, which you may find useful:
Sessions.xml settings:
UseNativeSequencing = True
ShouldBindAllParamters = True
UsesStringBinding = True
UsesStreamsForBinding = True
UsesBatchWriting = True
UsesJDBCBatchWriting = True
Actually, not sure if you need this information or not. Should you need further information, please do not hesitate to ask. Apologies again for my glaring lack of expertise in these matters, and any help would be greatly appreciated.
Thanks!

Answer 1

Hi,
I am going to use the following codes which I read from the ADF Developer Guide for SRDemo (with a little bit of adjustment):
public void fileUploaded(ValueChangeEvent event) {
InputStream in;
FileOutputStream out;
// Set fileUPloadLoc to "SRDemo.FILE_UPLOADS_DIR" context init parameter
String fileUploadLoc =
FacesContext.getCurrentInstance().getExternalContext().getInitParameter("SRDemo.FILE_UPLOADS_DIR");
if (fileUploadLoc == null) {
// Backup value if context init parameter not set.
fileUploadLoc = "/tmp/srdemo_fileuploads";
//get svrId and append to file upload location
Integer svrId =
(Integer)JSFUtils.getManagedBeanValue("userState.currentSvrId");
fileUploadLoc += "/sr_" + svrId + "_uploadedfiles";
// Create upload directory if it does not exists.
boolean exists = (new File(fileUploadLoc)).exists();
if (!exists) {
(new File(fileUploadLoc)).mkdirs();
UploadedFile file = (UploadedFile)event.getNewValue();
if (file != null && file.getLength() > 0) {
FacesContext context = FacesContext.getCurrentInstance();
FacesMessage message =
new FacesMessage(JSFUtils.getStringFromBundle("srmain.srfileupload.success") +
" " + file.getFilename() + " (" +
file.getLength() + " bytes)");
context.addMessage(event.getComponent().getClientId(context),
message);
try {
out = new FileOutputStream(fileUploadLoc + "/" + file.getFilename());
in = file.getInputStream();
for (int bytes = 0; bytes < file.getLength(); bytes++) {
out.write(in.read());
in.close();
out.close();
} catch (IOException e) {
e.printStackTrace();
} else {
// need to check for null value here as otherwise closing
// the dialog after a failed upload attempt will lead to
// a nullpointer exception
String filename = file != null ? file.getFilename() : null;
String byteLength = file != null ? "" + file.getLength() : "0";
FacesContext context = FacesContext.getCurrentInstance();
FacesMessage message =
new FacesMessage(FacesMessage.SEVERITY_WARN, JSFUtils.getStringFromBundle("srmain.srfileupload.error") +
" " + filename + " (" + byteLength +
" bytes)", null);
context.addMessage(event.getComponent().getClientId(context),
message);
Two questions:
One, I am going to read in the file as a byte[], from my readings, I know that I would have to use a custom UploadedFileProcessor to save files to the Database. How can I save that file as a blob into the Database? Can you let me know of some code samples? I am working with ADF Faces and TopLink, not Business Component.
Two, regarding your reply on 1/16, could you explain how do I map my byte[] to a blob?
Appreciate your assistance.
Lin