Calling another java class from a servlet

I am trying to write a web based form handling system (for a college project)
I have a servlet that responds to a user request for a form. I have another java program (HTMOut) that parses the xml file for the form and produces HTML output. When I call the HTMOut from the servlet it crashes the webserver (Tomcat). But if I call HTMOut from an ordinary java class it runs fine. If I call another test program from my servlet that works too.
Any ideas?

where does your HTMOut output? A file or a stream? I think it is better that HTMOut can output to a stream you can set externally.

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Calling another java class from a java class

Hi Friends,
I have a class tht works in 2 modes,depending upon which mode i am passing (gui or text) on the command line eg:
java myclass [mode]
I want to call this command from another java class,and i wrote this code:
try
         Process theProcess =
            Runtime.getRuntime().exec("java myclass "+args[0]);
      catch(IOException e)
         System.err.println("Error on exec() method");
         e.printStackTrace();
      }When i pass "gui" it works fine,but when i pass"text", the class completes and nothing shows up on the command prompt window,so can please somebody tell me how to make this work.
Thanks

As aniseed just pointed out, you could do something like this:
import javax.swing.*;
class Test extends JFrame {
     public Test(String title) {
          this.setTitle(title);
          this.pack();
          this.setSize(300, 300);
          this.setLocationRelativeTo(null);
          this.setDefaultCloseOperation(EXIT_ON_CLOSE);
     public static void main(String[] argv) { new Test(argv[0]).setVisible(true); }
public class Test2 {
     public static void main(String[] argv) {
          Test.main(argv);
}Run it by executing this command:
java Test2 "Title of Frame"See if that's not what you're looking for ...

How to call a Java class from another java class ??

Hi ..... can somebody plz tell me
How to call a Java Class from another Java Class assuming both in the same Package??
I want to call the entire Java Class (not any specific method only........I want all the functionalities of that class)
Please provide me some slotuions!!
Waiting for some fast replies!!
Regards
Smita Mohanty

Hi Smita,
you just need to create an object of that class,thats it. Then you will be able to execute each and every method.
e.g.
you have developed A.java and B.java, both are in same package.
in implementaion of B.java
class B
            A obj = new A();
             //to access A's methods
             A.method();
            // to access A's variable
            //either
           A.variable= value.
           //or
           A.setvariable() or A.getvariable()

How do you call a java class from the main method in another class?

Hi all,
How do you call a java class from the main() method in another class? Assuming the two class are in the same package.
Thanks
SI
Edited by: okun on May 16, 2010 8:40 PM
Edited by: okun on May 16, 2010 8:41 PM
Edited by: okun on May 16, 2010 8:47 PM

georgemc wrote:
To answer your impending question, either the method you're calling has to be static, or you need an instance of that other class to invoke it against. Prefer the latterAnd to your impending question after that: no, don't use the Singleton pattern.

How can I call a java class from within my program?

I was wondering if there's a platform independent way to call a java class from my program.

Here's my scenario. I'm working on a platform independent, feature rich, object-oriented command prompt program. The way I'm designing it is that users can drop classes they write into my bin directory and gain access to the class through my program. For example, they drop a class named Network.class in the bin directory. They would type Network network at my command prompt and gain access to all the methods available in that class. They can then type system.echo network.ipaddress() at my prompt and get the system's ip address. I have it designed that there's a server running in the background and the clients connect to my port. Once connected the end-user can enter their user name and password and gain access to the system. When they type a command they actually call another java program which connects to my server using a seperate thread. They can then communicate back and forth. I have it set that everything has a process id and it's used to keep track of who called what program. Once the program is done it disconnects and closes. Rather than getting into the nitty gritty (I didn't want to get into heavy detail, I know how everything will work) I'm really interested in finding out how I can call a java program from my program. I don't want it to be part of the app in any way.

I want to call External Java class from the PL/SQL

Hi,
I am using Oracle Apps R11i (11.5.7), I wanted to call external Java class from the PL/SQL. This external Java class is residing in another application server.
How do I do this.
I know one way. Develop C routine in Oracle Apps to call external java class and call this C routine from the PL/SQL.
Is there any simple method available? or any other method?
Thanks in advance.
-Venkat

First of all, this is a Java application you're talking about, right (i.e. it has a main() function)? It's not just a class that you're trying to instantiate is it? If it's an application, you obviously have to start a new virtual machine to run it (rather than using the virtual machine built into the database like stored java). I'm a little leary of your mention of an "application server" as this would more commonly mean that a virtual machine is already over there running with access to this class. In which case, you'd typically interface with SOAP or some other RPC API.
All that aside, as long as you have physical disc access (through NFS or whatever) to the class file, you could use a java wrapper class with a system call to do this. In fact, there is a thread in just the last day or so on this very forum that has the code to do just that (see " Invoking OS Commands from PL/SQL"). However, it's worth noting that the virtual machine will be running on the database server in this case and not the application server.

Calling a Java Class from PL/SQL

Hai,
I need a technique of calling a class file and invoke its
methods written in Java by PL/SQL for my intranet development.
PLease let me know if you have really experienced and won.
Thanks
JOhnson

First, to call a Java class from PL/SQL the class needs to be
deployed to the database. you can check the 8i documentation for
the instructions for loading Java into the database(LoadJava).
The document contains information on how to load the Java and
call it from PL/SQL. The following links should help.
Loading Java:
http://otn.oracle.com/docs/products/oracle8i/doc_library/817_doc/
java.817/a83728/03write6.htm
Invoking a Java Method in the database:
http://otn.oracle.com/docs/products/oracle8i/doc_library/817_doc/
java.817/a83728/04jserv2.htm
Gary (JDev Team)

Calling my Java class from JSP page

Hello, I am trying to call my Java class from my JSP page passing parameters to it and getting back a collection of result sets. Can someone tell me what I might be doing wrong:
JSP code to call Java class:
<%
String strEssUser = "test";
String strProcessingMonth = "JUL";
String strProcessingYear = "2002";
strQueryList=new ListReturn(strEssUser.toString(), strProcessingMonth.toString(), strProcessingYear.toString());
%>
I get this error when I try to run this JSP page using tomcat:
C:\Program Files\Apache Tomcat 4.0\work\Standalone\localhost\em\jsp\Test_0005fSummarySBU_0005fscreen$jsp.java:77: Class org.apache.jsp.ListReturn not found.
strQueryList=new ListReturn(strEssUser.toString(), strProcessingMonth.toString(), strProcessingYear.toString());
I'm not sure if this problem is the way I am calling the Java class, or if I have a problem in the Java code itself. Can anyone help?

Ok, I get a very strange error now:
org.apache.jasper.JasperException: Unable to compile class for JSPerror: An error has occurred in the compiler; please file a bug report (http://java.sun.com/cgi-bin/bugreport.cgi).
What is this??? Anyone?

How to: Calling a java class from asp?

Hello all i have a problem to call a Java class from a asp
Here what I do:
[JavaSays.java]
package JavaCom;
public class JavaSays
public String Hello()
return "Hello world" ;
then
javareg /register /class:JavaCom.JavaSays /progid:JavaCom.JavaSays
md c:\winnt\Java\TrustLib\JavaCom
copy JavaSays.class c:\winnt\Java\TrustLib\JavaCom
--Asp
--TestJavaCom.asp
<html>
<body>
<h1>Simple Test</h1>
<% Set ObjPrueba = Server.CreateObject("JavaCom.JavaSays") %>
<%= ObjPrueba.SimpleFn(5) %>
<hr>
</body>
</html>
when i try to run my asp
it tell me that:
Error type : Server Objetc, ASP 0177 (0x80040111)
ClassFactory can not find the class
any idea???
thanks.

I think the OP wants to use a class file as a COM object. I've never done that, but this URL:
http://support.microsoft.com/default.aspx?scid=KB;EN-US;q167941&
seems to indicate that you should have placed the class file into the c:\winnt\Java\TrustLib\ sub directory before you ran the JAvaReg bat file - I would re-run JavaReg and bounce IIS and associated services and see if that works out.
Good Luck
Lee

Calling a java class from asp

Hello all i have a problem to call a Java class from a asp
Here what I do:
[JavaSays.java]
package JavaCom;
public class JavaSays
public String Hello()
return "Hello world" ;
then
javareg /register /class:JavaCom.JavaSays /progid:JavaCom.JavaSays
md c:\winnt\Java\TrustLib\JavaCom
copy JavaSays.class c:\winnt\Java\TrustLib\JavaCom
--Asp
--TestJavaCom.asp
<html>
<body>
<h1>Simple Test</h1>
<% Set ObjPrueba = Server.CreateObject("JavaCom.JavaSays") %>
<%= ObjPrueba.SimpleFn(5) %>
<hr>
</body>
</html>
when i try to run my asp
it tell me that:
Error type : Server Objetc, ASP 0177 (0x80040111)
ClassFactory can not find the class
any idea???
thanks.

any idea???Yes, you are in the wrong forum, this is a Java forum, you have an ASP question, so i suggest you visit an ASP forum/site

Is there an easy way to call a java class from an applet?

Does anyone know of an easy way to call a server based java class from an applet? Has anyone done it or came across it? If yes how/where?
Cheers, Chris.

I'm not sure about the issue. Are you talking about "servelets"? "RMI"? Take a look at those issues.

Can we call a custom class from a servlet

Hi
Can we call a java class (not a delivered class by java) in a servlet. I am trying to call API.class which is written by me in a servlet. It is not giving an error at the import stage. But when i am trying to initialize the class object it is throwing up the following error:
Error 500--Internal Server Error
java.lang.NoClassDefFoundError: psft/pt8/joa/API
     at knet.Creditcall.(NBKServlet2.java:61)
     at knet.NBKServlet2.doGet(NBKServlet2.java:49)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:740)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:865)
     at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:120)
     at weblogic.servlet.internal.ServletContextImpl.invokeServlet(ServletContextImpl.java:915)
     at weblogic.servlet.internal.ServletContextImpl.invokeServlet(ServletContextImpl.java:879)
     at weblogic.servlet.internal.ServletContextManager.invokeServlet(ServletContextManager.java:269)
     at weblogic.socket.MuxableSocketHTTP.invokeServlet(MuxableSocketHTTP.java:365)
     at weblogic.socket.MuxableSocketHTTP.execute(MuxableSocketHTTP.java:253)
     at weblogic.kernel.ExecuteThread.run(ExecuteThread.java, Compiled Code)

Did you deploy your class with the web app? You can do this by placing your classes in a jar, and put that jar into the WEB-INF/lib folder or by copying your classes into WEB-INF/classes.

Calling a java class from abap/bsp

Hello,
I am still learning ABAP. I need to call a java class (a chart drawing library) from ABAP or from a BSP. What is the best way to do that ?
Basically I would create an object, pass data from a database and then get some binary data from that object (an image).
Hope you can help me
Sincerely,
Olivier Matt

/people/gregor.wolf3/blog/2004/08/26/setup-and-test-sap-java-connector-outbound-connection
check the above link and this forum too
Call Java Class and Methods from ABAP

Calling Custom Java Class from WCC?

How do I call a custom Java class from WCC when a certain metadata field is set to 'On' and at the time of check-in?
Thank you,
Randy

Randy,
You would only use the Intradoc classes if running as a service, service handler, filter or class alias as a component within WebCenter Content. In this case, since it is running inside WebCenter Content, you do not need to bundle the Intradoc classes since they are already on the classpath.
If you are trying to code something that will not run inside WebCenter Content, you want to use RIDC: http://jonathanhult.com/blog/2012/12/ridc-examples/
Jonathan
http://jonathanhult.com

Calling a java class from a java web service

I have deployed a web service to weblogic 8.1 SP5 and now i want to call a simple java class from that web service.How can i do it.

Hi jazz123,
There's an example in the [*Java Web Services Tutorial*|http://java.sun.com/webservices/docs/2.0/tutorial/doc/] : see Chapter 1: Building Web Services with JAX-WS - A Simple JAX-WS Client.

Calling another java class from a servlet

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