Re: Blob manipulation

[Quoted] [Quoted] "Aviran Levy" <avlevy2k_at_hotmail.com> ÓÏÏÂÝÉÌ/ÓÏÏÂÝÉÌÁ × ÎÏ×ÏÓÔÑÈ ÓÌÅÄÕÀÝÅÅ: [Quoted] news:ZfAB7.133$0N4.17635_at_news.shore.net...
> Hi,
> From a java application I'm trying to do:
> ...
> Blob b = rs.getBlob("ZIP_FILE");
> b.setBytes(1,byteArray);
> ...
> but apparently I get a runtime exception since my oracle jdbc driver
doesn't
> have implementation for the setBytes method. I probably need a newer
oracle
> jdbc driver. Is anyone know where can I find one?
> Is anyone having that problem too?
> My goal is to store a zip file on the Oracle server and manipulate it from
> the java application (avoiding calls for store procedures). If anyone
knows
> a better way to do that then please... I'll appreciate any help about it.
> Note: to use setBytes you have to use JDK1.4
> Thanks,
> -- Avi

1. Begin by using SQL statements to create the BLOB entry in the table. Use the empty_blob syntax to create the BLOB locator.

        stmt.execute ("INSERT INTO my_blob_table VALUES ('row1', empty_blob())");

2. Get the BLOB locator from the table.

    BLOB blob;
    cmd = "SELECT * FROM my_blob_table WHERE X='row1'";     ResultSet rest = stmt.executeQuery(cmd);     BLOB blob = ((OracleResultSet)rset).getBLOB(2);

3. Declare a file handler for the john.gif file, then print the length of [Quoted] the file. This value will be used later

    to ensure that the entire file is read into the BLOB. Next, create a [Quoted] FileInputStream object to read the

    contents of the GIF file, and an OutputStream object to retrieve the [Quoted] BLOB as a stream.

       File binaryFile = new File("YOUR_ZIP_FILE");
       System.out.println("john.gif length = " + binaryFile.length());
       FileInputStream instream = new FileInputStream(binaryFile);
       OutputStream outstream = blob.getBinaryOutputStream();

4. Call getBufferSize() to retrieve the ideal buffer size (according to calculations by the JDBC driver) to use in

    writing to the BLOB, then create the buffer byte array.

      int size = blob.getBufferSize();
      byte[] buffer = new byte[size];
      int length = -1;

5. Use the read() method to read the GIF file to the byte array buffer, then [Quoted] [Quoted] use the write() method to write it to

    the BLOB. When you finish, close the input and output streams.

    while ((length = instream.read(buffer)) != -1)       outstream.write(buffer, 0, length);     instream.close();
    outstream.close();

This fragment is from "Oracle8i JDBC Developer's Guide and Reference" charpter 7 "Working with LOBs and BFILEs"

Sergey M.

P.S. Knowledge is of two kinds. We know a subject ourselves, or we know where we can find information upon it. --Samuel Johnson Received on Thu Oct 25 2001 - 11:24:06 CEST