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Java Servlet. Catch full OData URL [duplicate]

This question already has answers here:
Servlet and path parameters like /xyz/{value}/test, how to map in web.xml?
(7 answers)
Closed 2 years ago.
I am trying to catch OData call in Java with WebServlet.
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
#WebServlet("/someservice/UserSet")
public class UserSetServlet extends HttpServlet {
#Override
protected void doGet(final HttpServletRequest request, final HttpServletResponse response) throws IOException {
//some functionality
}
}
When I call simply "http://somdomain.com/someservice/UserSet", then I get to service, but when I call "http://somdomain.com/someservice/UserSet("SOME_ID")", then I receive 404, that service is not found
Does someone know how I can configure Servlet for catching entire OData Request?
Thanks a lot!

Thanks to all answers. Solution - nohow. I starting migration to Spring Framework.

Servlet error HTTP Status 404 – Not Found Java Tomcat

I know that there were similar problems already, but non of the solutions worked for me. I checked the directories and I edited my `web.xml file a couple of times but it still does not work.
I am writing a simple servlet in Java running on Tomcat and I am getting the error:
HTTP Status 404 – Not Found
Type Status Report
Message /WorkshopForm/MainWorkshopForm
Description The origin server did not find a current representation
for the target resource or is not willing to disclose that one exists.
My servlet class is:
package workshop;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.Servlet;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
#WebServlet(description = "This registration form", urlPatterns = {
"/WorkshopForm" })
public class WorkshopForm {
public class MyServlet extends HttpServlet implements Servlet {
private static final long serialVersionUID = 13425L;
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String participantName = request.getParameter("participantName");
String participantSurname = request.getParameter("participantSurname");
String participantEmail = request.getParameter("participantEmail");
PrintWriter writer = response.getWriter();
writer.println("Welcome" + participantName + " " + participantSurname + " " + participantEmail);
}
}
}
My web.xml:
Tree in Eclipse:
Is it a problem with the web.xml file? I am thinking that maybe I have some mismatch with names or paths but I tried to solved it already and no idea why it is not working.

The URL pattern /WorkshopForm matches only the exact URL path /WorkshopForm. If you want the servlet to also handle longer paths like /WorkshopForm/MainWorkshopForm, you need to change the URL pattern to /WorkshopForm/*. Then you can call request.getPathInfo() in your servlet code to obtain the variable part of the path.
Another alternative is to use some JAX-RS framework to handle the mapping from URL paths to Java methods that handle individual paths.

cq5 can't create servlet resource

I create a servlet in my CQ5 application:
import java.io.IOException;
import javax.servlet.ServletException;
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.SlingAllMethodsServlet;
#SlingServlet(
label = "Example Servlet",
paths = {"/bin/project/signin"},
methods = {"GET"},
extensions = {"html"},
metatype = false
)
public class SignInServlet extends SlingAllMethodsServlet {
private static final long serialVersionUID = 796802690004962223L;
#Override
protected void doGet(SlingHttpServletRequest request,
SlingHttpServletResponse response) throws ServletException,
IOException {
doPost(request, response);
}
#Override
protected void doPost(SlingHttpServletRequest request,
SlingHttpServletResponse response) throws ServletException,
IOException {
response.setContentType("text/plain");
response.getOutputStream().print("Sigin Servlet");
}
}
i try to call it via rest-client but it return:
No resource found for url: http://localhost:4502/bin/project/signin
I also open Sling Resource Resolver at Felix side to test if it available. But i received:
NonExistingResource, path=/bin/project/signin
/bin/ already config in Apache Sling Servlet/Script Resolver and Error Handler at Fellix

In the #SlingServlet annotation you've declared that this servlet supports only requests with .html extension, so you should hit following URL:
http://localhost:4502/bin/project/signin.html
If you don't want to use the extension, remove appropriate parameter from the servlet annotation.

Two ways to help debug this type of situation —
The ServletResolver will allow you to check which Servlet a given GET or POST request will resolve against.
If you find the request you made that generated the 404 in the Recent Requests tab, it should tell you exactly what properties it has found by Sling when trying to resolve it.
E.g. in your case, I presume the 404 is giving something like:
LOG Resource Path Info: SlingRequestPathInfo: \
path='/bin/project/signin', \
selectorString='null', \
extension='null', \
suffix='null'
Comparing this against the settings in your annotation, there's an extension='null' here that wouldn't match against your servlet — which is binding only against a 'html' extension, as Tomek rightly says above.

Getting HTTP Status 404 error when trying to run servlet [duplicate]

This question already has answers here:
Servlet returns "HTTP Status 404 The requested resource (/servlet) is not available"
(19 answers)
Closed 6 years ago.
I have a problem with my simple servlet that I am trying to run, Hello.java. I made it in eclipse, then placed the file it in the webapps/ServletTest/WEB-INF/classes folder and compiled it, creating the file Hello.class in the same folder. I then modified my web.xml file to map the servlet and tried to run it through the following address
http://localhost:8080/ServletTest/Hello
However, this did not work, giving the following error
HTTP Status 404 -
type Status report
message
description The requested resource is not available.
Apache Tomcat/7.0.42
The mapping in the web.xml file looks like this:
<servlet>
<servlet-name>Hello</servlet-name>
<servlet-class>Main.Hello</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Hello</servlet-name>
<url-pattern>/Hello</url-pattern>
</servlet-mapping>
The code of the servlet:
package Main;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
#WebServlet("/Hello")
public class Hello extends HttpServlet {
private static final long serialVersionUID = 1L;
public Hello() {
super();
}
protected void doGet(HttpServletRequest request, HttpServletResponse
response) throws ServletException, IOException {
PrintWriter out = response.getWriter();
response.setContentType("text/html");
String path = request.getContextPath();
String ip = request.getRemoteAddr();
out.print("<html>" +
"<title>Hello</title>" +
"Hello World"+ "<br>" +
"Your ip is: " + ip + "<br>" +
"Your path is: " + path
+ "</html>");
}
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
}
}

The compiled Hello.class file should be in the folder
webapps/ServletTest/WEB-INF/classes/Main
since it's declared to be in package Main.
Also, you can see Tomcat's startup logs in /logs/catalina.out or /logs/catalina.log, depending.
Also, Suresh is right in the comments, use either a <servlet> declaration or #WebServlet. Don't use both.

Try to delete web.xml.
Annotation #WebServlet("/Hello") is enough for Tomcat 7+

If the root folder not having proper permission you will face this issue. So please check the root folder property and remove read only permission and add user to full access permission in security tab.

Does RequestDispatcher work over multiple webapps in one servlet container?

Does RequestDispatcher work over multiple webapps ?
I'm asking because I had a single webapp working fine that uses RequestDispatcher rather than redirects so state isnt lost when displaying error and feedback messages.
However I now need to split some functionality between two webapps, so initial call is made from a webpage hosted on webapp1, calls webapp2 which eventually returns user to a page hosted on webapp1.
Clearly if webapps and webapp2 were on different websites using RequestDispatcher would not be possible but is it if both webapps are deployed within the same instance of a servlet container (tomcat 7)
Update
Got the request dispatcher part to work as explained in answer but am unable to retrieve data put in my webapp2 which iss why Im using it
i.e
webapp2 called , does some processing and then dispatches to a jsp on webapp1
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
HttpSession userSession = request.getSession(true);
String emailAddress = ......
String nextPage = /finish.jsp
userSession.setAttribute("DATA", emailAddress);
ServletContext otherContext = getServletContext().getContext("/webapp1");
otherContext.getRequestDispatcher(nextPage).forward(request, response);
}
webapp2 jsp file contains
...
<p>Email(<%=((String)session.getAttribute("DATA"))%>)</p>
...
but always displays null
Update 2 **
Im wondering if Im misunderstanding what crossContext="true" actually does . Does it make the same HttpSession availble in different webapps, or does it just make the ServletContext from one webap availble to another and hence allow one webapp to see the HttpSessions of another webapp ?
Im starting to think what Im doing is a bad idea as Ive always been keen to use vanilla servlet setups and never want to tie myself to a particular implementation. I think it might help if I explain why I flet the need to split the webapps in the first place.
I had a one webapp (webapp1), that was a website about a product I develop and code for purchasing that product using Google Checkout (now Google Wallet).
I then added created a new webapp for a new product (webapp2).
I then tried to add Google Checkout for new product into webapp2, but realised I couldnt do this easily because Google Checkout requires me to provide it with a url which it can call by application once it has processed payment so that I can then send
user a license. The url was already set to a servlet in webapp1, but
it wouldn't make sense for webapp1 to process payment s for product 2.
One option was to merge webpp1 and webapp2 into one webapp, but this goes against my general view of keeping things modular, it
would also mean evey time I would want to make chnages for one
product Id have to redeploy everything. It also meant big
modifications to webapp1 which I really didnt want to modify as it
was working and stable.
The alternative was to create webapp3 and then google url can point to this, and use this for processing purchases of product 1
and product 2 which is what Ive done. But the problem is when
purchasing product 1 the starting page is in webapp1 , and once
purchase has taken place I want to go back to a page in webapp1, but
only webapp3 has the details of the user who has just made the
purchase which I wanted to display on on the page in webapp1.

This is due to security reasons by default not possible. You need to configure Tomcat first to enable exposing the ServletContext of the current webapp to other webapps. This is to be done by setting the crossContext attribute of context.xml to true.
<Context ... crossContext="true">
Once done that, then you can use ServletContext#getContext() to obtain the other servlet context by its context path and finally use the RequestDispatcher as obtained by ServletContext#getRequestDispatcher() the usual way.
E.g.
ServletContext otherContext = getServletContext().getContext("/otherContext");
otherContext.getRequestDispatcher("/WEB-INF/some.jsp").forward(request, response);

Yes.
The first thing you need to do is get hold of a ServletContext for the other webapp. You do that with ServletContext::getContext on your own ServletContext, passing the context path of the other webapp.
Then, you simply do ServletContext::getRequestDispatcher as normal on the foreign context.
I haven't actually tried this, but i 100% guarantee that it will work.

I am not sure about different servlet container. But it works for same container by using
getServletContext().getContext() method.
First you need to make changes in below file
(Windows) C:\Program Files\Apache Software Foundation\Tomcat 7.0\conf\context.xml
Set value of crossContext to true.
context.xml
<Context crossContext="true">
<!-- Default set of monitored resources -->
<WatchedResource>WEB-INF/web.xml</WatchedResource>
<!-- Uncomment this to disable session persistence across Tomcat restarts -->
<!--
<Manager pathname="" />
-->
<!-- Uncomment this to enable Comet connection tacking (provides events
on session expiration as well as webapp lifecycle) -->
<!--
<Valve className="org.apache.catalina.valves.CometConnectionManagerValve" />
-->
</Context>
Please note that crossContext="true".
Suppose you have two web applications with name InterServletComm1 and InterServletComm2
having servlets Servlet1 and Servlet1 in each web application respectively. Then the code in each servlets goes as follows:
Servlet1.java
package interServletComm1;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class Servlet1
*/
#WebServlet("/Servlet1")
public class Servlet1 extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* #see HttpServlet#HttpServlet()
*/
public Servlet1() {
super();
// TODO Auto-generated constructor stub
}
/**
* #see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
response.setContentType("text/html");
PrintWriter pw = response.getWriter();
request.setAttribute("name", "WebApp1");
ServletContext context = getServletContext().getContext("/InterServletComm2");
RequestDispatcher rd = context.getRequestDispatcher("/Servlet2");
rd.forward(request, response);
}
/**
* #see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}
}
Servlet2.java
package interServletComm2;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class Servlet2
*/
#WebServlet("/Servlet2")
public class Servlet2 extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* #see HttpServlet#HttpServlet()
*/
public Servlet2() {
super();
// TODO Auto-generated constructor stub
}
/**
* #see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
response.setContentType("text/html");
PrintWriter pw = response.getWriter();
String name = (String) request.getAttribute("name");
pw.println("This is web application 2.");
pw.println("<br>The value received from web application one is: " + name);
}
/**
* #see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}
}
Above code sends attribute name from InterServletComm1 and it is received in InterServletComm2.
Please let me know if this answer is not clear.