Calling Servlet from a java class

Hi,
I don�t know what I�m doing wrong...
I try to call a servlet located in a tomcat webserver, from a class, and capture its output. I use an URLConnection object... Everything is all right when I want to get an html page, but, it reports an IOException (FileNotFoundException) when the requested resource is a servlet.
This servlet is working correctly.
Can�t I use an URLConnection to access servlets?
Cheers

try setting up the user agent property of HTTP protocol to a browsers,its worth a shot.
Cheers
Khalid

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Calling servlet from a java program

Hi
I need to call a servlet's doPost() method from a java program. I have a specific situation, where I need to call servlet from a java program. DUring this call I need to pass a file and two string to the servlet. Servelt after receiving the file and string uploads the file to the server at a specified location. I am stuck up as how to call servlet from a java program instead of a HTML or JSP.
Can anyone help me to start with this.
any suggestion is welcome.

You have to establish a URLConnection with servlet from your java program.
URL servletURL = new URL("http://localhost:8080/Myservlet?str1=abc&str2=def");
URLConnection servletConnection = servletURL.openConnection();you can get the objectOutputStream
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oos.writeObject(your file object);-------------------------------------------------
In the servlet u can get the strings using request.getParameter("str1");
In the servlet u can get the strings using request.getParameter("str2");
file = new ObjectInputStream (request.getInputStream()).readObject()a lot of resources are available on this ...
hope this helps :)

Calling Servlet from a java prog?

Hi all,
I am calling servlet from a java prog (Java Agent in Lotus Notes) by using URL and URLConnection object. how can i trigger the Servlet By using doPost method .I have to send some parameter also.
Thanx
Muthu

you need to open a connection to the servlet. Then you must call getInputStream() and getOutputStream() and use them in any way you see fit. I was trying this before and could not get POST to work unless I openned the input stream from the servlet. Strange... but doGet worked without openning the input stream???
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Call Bean from normal java class

Dear Friends,
Is it ok to call an entity bean or session bean frm normal Java class.
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Is there a special way to lookup the beans from normal java classes.
Thanking You,
Chamal.

it is ok and very commonly done.
Note that the simple java program must be running in the same local network. You cannot have the java program and EJBs distributed over internet. (I m not certain of it, but mostly I shoudl be correct. If you have the resources, try it out and let me know)
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2. Another EJB
3. a simple java program.
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sample code (this method is being called from the main method of a simple java program. it is self explanatory):
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How choose between post and get when calling a servlet from a java class ??

Hi !!
I have an urgent question : in fact some java programs that call servlets are published on the web, and the principle is to make an url.openconnection() to reach the servlet.
What I don't understand is how we choose if we want to call the get or the post method on the servlet ?????
please answer very fast.....
thanks...

from the URL documentation of openConnection():
"If for the URL's protocol (such as HTTP or JAR), there exists a public, specialized URLConnection subclass belonging to one of the following packages or one of their subpackages: java.lang, java.io, java.util, java.net, the connection returned will be of that subclass. For example, for HTTP an HttpURLConnection will be returned, and for JAR a JarURLConnection will be returned."
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Calling a servlet from a Java Stored Procedure

Hey,
I'm trying to call a servlet from a Java Stored Procedure and I get an error.
When I try to call the JSP-class from a main-method, everything works perfectly.
Java Stored Procedure:
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String servletURL = "http://127.0.0.1:7001/servletname";
URL url = new URL(servletURL);
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public void doGet(HttpServletRequest request, HttpServletResponse response)
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Integer id = new Integer(10);
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Grant:
call dbms_java.grant_permission( 'JAVA_USER', 'SYS:java.net.SocketPermission','localhost', 'resolve');
call dbms_java.grant_permission( 'JAVA_USER','SYS:java.net.SocketPermission', '127.0.0.1:7001', 'connect,resolve');
Package:
CREATE OR REPLACE PACKAGE pck_jsp AS
PROCEDURE callServlet();
END pck_jsp;
CREATE OR REPLACE PACKAGE BODY pck_jsp AS
PROCEDURE callServlet()
AS LANGUAGE JAVA
NAME 'JSP.callServlet()';
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Architecture:
AS: BEA WebLogic 8.1.2
DB: Oracle 9i DB 2.0.4
Exception:
java.io.StreamCorruptedException: InputStream does not contain a serialized object
at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java)
at java.io.ObjectInputStream.<init>(ObjectInputStream.java)
The Servlet and the class work together perfectly, only when I make the call from
within the database things go wrong.
Can anybody help me.
Thank in advance,
Bart Laeremans
... Desperately seeking knowledge ...

Look at HttpCallout.java in the following code sample
http://www.oracle.com/technology/sample_code/tech/java/jsp/samples/jwcache/Readme.html
Kuassi

Is it possible to call a method in a servlet from a java script ?

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You can
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How can I call a pop up window from a java class ?

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user504072 wrote:
It was possible to do it in ASP .NET even from the server side with the method Page.ClientScript. What do you think what Page.ClientScript stands for?
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How to call a Java class from another java class ??

Hi ..... can somebody plz tell me
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Calling another java class from a java class

Hi Friends,
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As aniseed just pointed out, you could do something like this:
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java Test2 "Title of Frame"See if that's not what you're looking for ...

Calling servlets from main()?

Hi
I would like to know that while calling servlets from another class having main(), how can we set the type of request i.e. put, post or get?
Thanks

use the method - setRequestMethod( "POST") of HttpURLConnection for setting the method to POST.Similarly for other methods..
You could find [url http://java.sun.com/developer/JDCTechTips/2004/tt0210.html#2]this useful

Wot all ways are there to call servlet from jsp

hi all
i want to know wot all methods are available
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thanx

hi all
i want to know wot all methods are available
so that i can call servlet from jsp
the one which i know is using RequestDispatcher
wot are others ?
thanxhi here are few ways... to call servlet from jsp...
these are just generic syntax.
Form:
<form action="ServletPath">
Link:
Directives & Action tags :
<%@ page import="ServletPath" %>
     <%@ taglib uri="ServletPth" %>
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     <jsp:forward page="ServletPath">
     <jsp:useBean class="ServletPath"> (Not sure about this useBean)
hope you got your answer.
regards,
immu

How to call Servlet from jsp page and how to run this app using tomcat..?

Hi ,
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well....my problem is as follows:
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plz help me.

How to execute a jsp instruction from a java class?

How to execute a jsp instruction from a java class?
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I'll detail my problem:
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<tag class>Tag1<.....
The java file Tag1 has method:
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I think that I have to pass the object global as a parameter to the class Tag1. How to do that?
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The output is <%= hello world %> not hello world.
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Calling JPA from a Java Stored Procedure

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Hi Johnny:
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Best regards, Marcelo

Calling Servlet from a java class

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