Palin old java class Servlet Communication issue

I am sending data to servlet and able to get back data to plain old java class using url.openConnection mechanism.But I want to redirect another jsp page after servlet get data from java calss.
Can any one help me please
Regards
Madhu

What alternative could there be?
You're calling a webserver which just happens to be running a Java process to generate its output.
You don't have to know that, that's the whole point in using servlets...
So no, there's no way (and if there is it's a terrible breach in the security of your server).

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Accessing ServletContext from Java class Data Control

I'm writing some business service classes as plain old java classes that will be bound to a JSP using ADF and STRUTS. The business logic requires the real path of the servlet context to access a file. How do I call servletContext.getRealPath("/WEB-INF/test.xml")?
I know this is mixing web tier code into model code, but I don't know any other way to do this.
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Ok, it looks like I'll have to define my own action class and pass the pathname on to the data control class.

How to hot deploy java class?

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Does this work ??
I was unable to achieve hot deployment using REDEPLOY file.
Sheng Sheen <[email protected]> wrote in message
news:[email protected]..
You need to create a REDEPLOY file and touch the file.
From the documentations:
Dynamic Redeployment of Exploded Applications
You can also dynamically redeploy applications or application components
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"Alex" <[email protected]> wrote in message
news:[email protected]..
I write some java class and put them into the weblogic\class folder to
replace the old java class files.
When I run the program, the server still run the old java class.
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The server must restart, when I want to run new java class?
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Communication between 2 servlets/java classes.

Hi,
Ive a problem. Not sure if its a simple one.
I have a web app with servlets (say Servlet1, Servlet2, etc.) in it. I use a SQL query in Servlet1 and fetch an employees information (say empinfo) from the database. This is a string value. Now, I need to pass this empinfo to Servlet2.
I might sound dumb till here but please continue till the end to know what I still have to say
1.     I tried using getters and setters. Servlet2 has the empinfo value I need. This is the first time Servlet2 is accessed.
2.     But, think that Servlet1 is transferring the control to an html page. And, this html page submits its parameters (say manager) to Servlet2. And, when this html passes its control to Servlet2, the empinfo value I need is gone because I used empinfo as a class member/global.
3.     So, when the control enters the Servlet2 the second time everything is lost and this is when I need the empinfo value.
4.     I cannot make the empinfo value in Servlet2 static because it keeps changing.
Note: I tried with all these: httpsession, reflection, etc. but nothing seems to fulfill my task.
Actually, Servlet2 lets the users to download the empinfo when a link on the html page (which sends the parameters to this servlet) is clicked.
I used httpsession to store this empinfo in Servlet1 and used to grab the value in Servlet2.
Then, I ran this app on my localhost. Then:
Step1: I opened up one browser and when I clicked the link on html, I checked the empinfo value. It was fine.
Step2: I opened up another browser and when clicked the link on html, I checked the empinfo value. It worked again.
Step3: Now, I went back to the html page in the browser1 and clicked the link and checked to see the empinfo value and now it has the value of that in browser2.
The empinfo always had the latest value. Previous values are overwritten.
If I could find a way to cache the Servlet1 object to use it in Servlet2 then I think my job is half done because even if I let Servlet2 keep a reference of the Servlet1, the html page is ruining the desired result.
If anyone can let me know how to do this with normal Java classes even that works for me.
Thanks in advance.

Thanks for the reply.
Actually, when I used the session the IE browser behaved properly and its the FireFox that was weird.
I think this is because Firefox uses single cookie for many instances of itself.
Thanks again.

Standard Java class communicating with a servlet

Hey,
I am trying to access a standard java classes member via a servlet class however the data is never received even though the member is visible on compilation. is there something Im doing wrong ?
public class Start {
//lots of stuff
     static List<Plug> plugList = Collections.synchronizedList(new LinkedList<Plug>());
//lots more stuff
public class wah extends HttpServlet{
        public void doGet( HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException{
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Don't post all your code. Instead, make a simplified version of the code that demonstrates what your problem is and that we could compile and see what is going on. Make it as simple as possible but still demonstrating the problem.
Who knows, when you make the SSCCP (small, self contained, compileable program) you will find your mistake as well.
But without seeing any code all I can say is that the date you are accessing in the list has not been made available when you try to get it from the servlet. Perhaps the servlet call is blocking the other threads from accessing the list to put data into it, perhaps the other threads haven't begun working yet, perhaps the list you give to the servlet isn't the same list (but instead a copy of the list) that the data is being entered into, or many other reasons.
One thing I would assume you need to do, since the Servlet is the data consumer, you need to make sure the data has been entered before the servlet tries to read it. The best way to do that is to put a wait() in the servlet code so that it knows it can't do anything until the producers are finished. Then the producers would add a notify() to tell the servlet to go ahead and display the data.
So some modification might be:
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//lots of stuff
     static List<Plug> plugList = Collections.synchronizedList(new LinkedList<Plug>());
        //marker to let servlet know that it can consume data
        private static boolean done = false;
        //producers call this method when list is ready for use
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How to convert old Java Servlets to OSGi "Servlet" Bundles

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import java.io.IOException;
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import org.apache.felix.scr.annotations.sling.SlingServlet;
import org.apache.sling.api.SlingHttpServletRequest;
import org.apache.sling.api.SlingHttpServletResponse;
import org.apache.sling.api.servlets.SlingSafeMethodsServlet;
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    // @Reference
    // private Repository repository;
    private static final long serialVersionUID = 6239754936223276983L;
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        response.getWriter().print("whatever");

Issue with Java Class based DataControls.

Hi,
I'm actually working with JDev 11.1.1.3.0.
And we got a requirement to build a search page which should create a dynamic query. And we are not using ADF BC in this project.
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=======
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You could try the following to see where the class was loaded from.
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Hello,
I try to call a servlet from java class
but is dose not work
what should be the problem
   public void callServlet()
          try
                        // xxservlet is the servlet name
               URL url = new URL("http://www.mydomain.com/xxservlet");
               URLConnection hpCon = url.openConnection();
               hpCon.setDoOutput(true);
               OutputStreamWriter out = new OutputStreamWriter(hpCon.getOutputStream());
               out.write("This Is a Test");
               out.flush();
               out.close();
          }catch(Exception ex){ex.printStackTrace();}
// My Servlet is in package servlets
public class XXServlet extends HttpServlet
    public void service(HttpServletRequest req, HttpServletResponse resp) {
        try {
             ServletInputStream sin = req.getInputStream();
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                ServletInputStream sin = req.getInputStream();
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// web.xml
<servlet>
       <servlet-name>xxservlet</servlet-name>
       <servlet-class>servlets.XXServlet</servlet-class>
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</servlet-mapping>
}regards
Edited by: the_Orient on Mar 30, 2009 3:16 AM

I have start servlet from brwoser only to test that servlet works fine
A gain what I need
I want to call a servlet from a javs class
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URLConnection hpCon = url.openConnection();
hpCon.setDoOutput(true);
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out.flush();
out.close();// Servlet
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problem file can not be created
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}I hope that is clear

Importing java class in servlet

hi,
i need to import a java class file in a servlet. how do i do that.
also, when i remove the following lines, the import & the line following line,
//JavaClass class=new JavaClass();
msgsend class=new msgsend();
it compiles ok, else i get the error,
out.println cannot resolve symbol.
the code of the servlet is as follows:
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpServlet;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import java.sql.*;
import java.io.*;
import java.util.*;
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out.println("<head>");
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out.println("</head>");
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out.println("</B><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><pagebreak>");
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pls help,
thanx,
ashna

You have to do like the others import. You have to put import and the complete path(with all the packages).
For example:
import mypackage.msgsend;
and if you wouls like to import all the classes of a package use:
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I have a normal java-class that is working with request/response Objects. From within this class I want to call a local servlet, let it do some work with the request and the response and then return it to the class.
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The getServlet()-method is not working any more.
Maybe somebody has an idea.
Thanks a lot,
Matthias

Hi,
I have a normal java-class that is working with
request/response Objects. From within this class I
want to call a local servlet, let it do some work with
the request and the response and then return it to the
class.
I guess the RequestDispatcher can only be called from
within a Servlet, but my class is not a servlet.
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URL url = new URL(ServletPath);
URLConnection connet = url.openConnection();
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Thnks

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Hi guys..!
I have a java class that I would like to import or use in my servlet class....does any of you knows how to do that...?? and in which directory should I put the java class..??
Any help will be appreciated...
Thanks,

Same way you would import any other class into any other class. With an "import" statement. There is nothing special about servlets in this case, and there is nothing special about the fact that the class was written by you. The only requirement is that imported classes must be in a package.

Palin old java class Servlet Communication issue

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