Re: JDBC + PostgreSQL + LargeObjects

Thank you very much! now it works perfectly! w00t!

On Mon, 18 Feb 2002 15:37:59 -0500
Marc Lavergne <mlavergne-pub(at)richlava(dot)com> wrote:

> I would just change this:
>
> ...
> int i=0;
> for(i=0; i<obj.size() ; i++)
> {
> out.write(buf[i]);
> }
> ...
>
> to this:
>
> ...
> out.write(buf);
> out.flush();
> out.close();
> ...
>
> Writing it out 1 byte at a time would be way too inefficient and is
> probably why your CPU pegs.
>
> Cheers,
>
> Marc
>
>
> Paulo Delgado wrote:
>
> > Ok folks, now it works! thank you all! (i'm using a servlet to avoid the white spaces)
> > Now i have another problem, when the servlet is writing the bytes to the outputstream, the cpu load increases to 100%, i guess the problem is in the for() block, should i look for another way of doing this? or use perl? or what?
> >
> > check it out:
> >
> > import javax.servlet.*;
> > import java.io.*;
> > import javax.servlet.http.*;
> > import java.sql.*;
> > import org.postgresql.largeobject.*;
> >
> > public class show_coctel extends HttpServlet
> > {
> > public void doGet(HttpServletRequest request , HttpServletResponse response) throws ServletException, IOException
> > {
> > ServletOutputStream out = response.getOutputStream();
> > response.setContentType("image/jpeg");
> > try
> > {
> > Class.forName("org.postgresql.Driver");
> > }
> > catch(ClassNotFoundException cnfex)
> > {
> > cnfex.printStackTrace();
> > }
> > try
> > {
> > Connection mycon;
> > mycon= DriverManager.getConnection("jdbc:postgresql://localhost:5432/database", "username" , "password");
> > mycon.setAutoCommit(false);
> >
> > // Get the Large Object Manager to perform operations with
> > LargeObjectManager lobj = ((org.postgresql.Connection)mycon).getLargeObjectAPI();
> > PreparedStatement ps = mycon.prepareStatement("SELECT pic FROM cocteles WHERE month='"+request.getParameter("m")+"' AND year="+request.getParameter("y"));
> > ResultSet rs = ps.executeQuery();
> > if (rs != null) {
> > while(rs.next()) {
> > //open the large object for reading
> > int oid = rs.getInt(1);
> > LargeObject obj = lobj.open(oid , LargeObjectManager.READ);
> >
> > //read the data
> > byte buf[] = new byte[obj.size()];
> > obj.read(buf, 0, obj.size());
> >
> > //do something with the data read here
> > response.setContentLength(obj.size());
> > int i=0;
> > for(i=0; i<obj.size() ; i++)
> > {
> > out.write(buf[i]);
> > }
> > // Close the object
> > obj.close();
> > }
> > rs.close();
> > }
> > ps.close();
> > mycon.close();
> > }
> > catch(SQLException sqex)
> > {
> > out.println(sqex.toString());
> > }
> > }
> > }
> >
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> >
> >
>
>
> --
> 01010101010101010101010101010101010101010101010101
>
> Marc P. Lavergne [wk:650-576-7978 hm:407-648-6996]
> Senior Software Developer
> Global Knowledge Management
> Worldwide Support Technologies
> Openwave Systems Inc.
>
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