Servlet Accessibility on browser with servlet running on a different folder

Hello everybody,
I have all these executed on Tomcat Server 4.1 version.
I have a servlet, say HelloServlet. I put it under the examples directory and execute it from the browser there is no problem.
the path : http://localhost:8080/examples/servlet/HelloServlet.
However, if I copy the same servlet to a different folder and try to execute it, I get a HTTP 404 error.
Can I have an idea as to how the servlet that is available in a different folder be executed.
here the url is
http://localhost:8080/docprime/servlet/HelloServlet, wherein docprime refers to my folder where I have the servlet.
Is there anything I should do with the web.xml file or properties file to do anykind of mapping.....etc..
I have been struggling with this since yesterday, but not making any kind or progress..
Kindly help..
Thanks n regards,
Sajiv
Chennai, India.

You would have add the vitual path in your server.xml. You could find this file under toplink config folder. Search for it in the toplink installation folder.
Add a <context> tag with proper inofrmation such as the path etc. Check out the document http://jakarta.apache.org/tomcat/tomcat-4.1-doc/config/context.html.
HTH.

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Sorry, I don't think I can help you without more information.
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import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.http.HttpServlet;
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[email protected]

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First, post your code in tags if you want people to read your code...

Inexplicable delays in browser-to-servlet-to-browser communication

We are seeing some inexplicable "pauses" in the round-trip from
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mg
Mike Gorman, Director of Architecture
YOUcentric, Inc.
Charlotte, NC
704-643-1000 x518
http://www.youcentric.com

If you are using 5.1 and you have ELF turned on (see docs).
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mbg
In article <[email protected]>, [email protected] says...
Here are a few top of the head suggestions:
1. You can log the time when the request is received by the servlet and
when the output stream is closed. That should give you a fair idea of
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2. Try flush() to send stuff to the browser after every few lines of
write(). It helps.
3. IE does wait for the whole HTML to come in before it displays unlike
Netscape which shows the streaming data. So switch browser and check.
4. Make sure you are not using the SingleThread model even though that
does not explain the delay encountered by a single user.
If these do not help, you would need to give more insight into the code.
- Anshum
Mike Gorman wrote:
We are seeing some inexplicable "pauses" in the round-trip from
browser-to-servlet-to-browser communication. The browser and Weblogic
instance are on different machines, so correlating absolute times has
been difficult. So at this point it's hard to tell whether the browser
request is not being received immediately by the servlet, or the servlet
response is not being received immediately by the browser... or perhaps
it is, but maybe the response stream isn't "closing" properly, causing
the browser to think there's still more to come.
If the browser request is not being received immediately by the servlet,
it could be because the execute thread count is so low that the request
is being blocked until a thread is availble to service it. But our
thread count is set to 30 and this is with just a single user hitting
the servlet.
If the servlet response is not being received immediately by the
browser, or is not being closed properly, what could cause that?
Occassionally, I have been able to account for some of the "delay"
time. Our servlet does the usual stuff: writes out to the response
writer and then closes the writer:
PrintWriter writer = response.getWriter();
writer.write( htmlString );
writer.close();
I have seen the writer.close() method taking a long time - over 5
seconds on one occassion! What could it be doing?
==================================================
NewsGroup Rant
==================================================
Rant 1.
The less info you provide about your problem means
the less we can help you. Try to look at the
problem from an external perspective and provide
all the data necessary to put your problem in
perspective.

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</web-app>
Thanks in advance

That web.xml doesn't look right to me.
what's that <database> tag? I would only expect to see a <resource-ref> in the web.xml.
I would not touch the server.xml. Create a context.xml and put it in your META-INF directory. That should look like this:
<?xml version="1.0" encoding="UTF-8"?>
<Context path="/your-path" reloadable="true" crossContext="true">
    <Resource name="jdbc/your-jndi"
              auth="Container"
              type="javax.sql.DataSource"
              username="your-username"
              password="your-password"
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              url="your-url"
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</Context>%

Using Toplink with Servlets in a Clustered application server

I am having some problems with Toplink.
Basically, I have a collection of HttpServlets that manipulate a domain object and its various collections of objects. The general technique is to place the domain object in the HttpSession, and have each Servlet modify this object by retrieving it, modifying it, and storing it when necessary. The problem is that since this application is running in a clustered environment, the object in the session may or may not be the same object returned from Toplink. It may be a serialized clone of the object from another server on the cluster.
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Anyway, my question is, what is the general pattern for handling an object being manipulated on a HttpSession in a clustered environment, where this object(s) may or may not be the actual objects returned from Toplink? My goal is to have a factory return one DatabaseSession per cluster server, and be able to load, store, and manipulate these objects in the HttpSession.
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import java.io.*;
import java.util.*;
import oracle.toplink.expressions.*;
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return new ArrayList(v);
public Customer getCustomerForUpdate(Customer c)
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return (Customer) unit.registerObject(c);
public Form getCustomer(String id)
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Expression exp = builder.get("id").equal(id);
return (Customer) session.readObject(Customer.class, exp);
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unit.deepMergeClone(cust);
unit.commitAndResume();
private synchronized DatabaseSession getDatabaseSession()
if (session == null)
session = project.createDatabaseSession();
session.login();
session.setLog(new PrintWriter(System.out));
session.logMessages();
return session;
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release();
public void release()
unit.release();
session.release();
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Thanks for any help,
Jason Wilson

Hi Jason
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-find the object that they are working with (based on information in the HttpSession)
-if the object is to be edited then a UnitOfWork provides clones of the object (this isolates you from changes that some other user makes to the same object)
-at the end, commit the changes to the object.
When the user makes another request, the object they read will have their changes. So, functionally, this is the same as storing the actual object in the HttpSession, except TopLink can provide proper ACID behavior for any updates that you decide to make. And don't worry about the added "expense" of having to query at the beginning of each servlet request; if you are storing the "id" of the object in your HttpSession, then you a simple cache hit is all that is required to get back the correct object. You don't have to go the database at all.
JIM

Servlet Accessibility on browser with servlet running on a different folder

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