As mentioned in Restlet docs it has feature called "tunneling". Does this feature exist in RESTEasy too?
Servlet below supports "tunneling" by delegating "method" parameter from request.
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher;
public class TunnelingDispatcher extends HttpServletDispatcher {
#Override
protected void service(HttpServletRequest httpServletRequest,
HttpServletResponse httpServletResponse) throws ServletException,
IOException {
String method = httpServletRequest.getParameter("method");
if (method == null) {
method = httpServletRequest.getMethod();
} else {
method = method.toUpperCase();
}
service(method, httpServletRequest, httpServletResponse);
}
}
Related
In NetBeans / Java - exception breakpoint (for Throwable) does not catch exceptions (RuntimeException in code of library for servlet). If you search tediously, you can find a purple stop line but without looking into the state of variables, etc. VS.NET does not have such ailments - it stops where you need it and everything is clear.
Is this a NetBeans problem or Java? How to get rid of breakpoint problems?
In here example would give you basic understanding of Exception Handling in Servlet
Actually putting a break point you can not catch a servlet exception because of it is happening before reaching the end point then you have to do something like this
When a servlet generates an error developers can handle those exceptions in various ways
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("/SampleExceptionHandler")
public class SampleExceptionHandler extends HttpServlet {
private static final long serialVersionUID = 1L;
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
exceptionProcessor(request, response);
}
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
exceptionProcessor(request, response);
}
private void exceptionProcessor(HttpServletRequest request,
HttpServletResponse response) throws IOException {
// Analyze the servlet exception
Throwable throwable = (Throwable) request
.getAttribute("javax.servlet.error.exception");
Integer statusCode = (Integer) request
.getAttribute("javax.servlet.error.status_code");
String servletName = (String) request
.getAttribute("javax.servlet.error.servlet_name");
if (servletName == null) {
servletName = "Unknown";
}
String requestUri = (String) request
.getAttribute("javax.servlet.error.request_uri");
if (requestUri == null) {
requestUri = "Unknown";
}
}
}
I'm attempting to create a login process using JSPs and linking them to my MySQL database. The issue I have encountered is an internal error (500) in my browser after I click "login".
I have setup my web.xml for the servlet ValidateLogin.java and I know that is not the issue. Can someone please help me here? I'll place down my code below that involves my HtmlServlet Request and Response.
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.ResultSet;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class ValidateLogin extends HttpServlet {
Connection connect;
ResultSet result;
String username, password, query;
DatabaseConnection database_connection;
protected void processRequest(HttpServletRequest request,HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UF-8");
PrintWriter out = response.getWriter();
try {
// Code Here...
#Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
#Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
#Override
public String getServletInfo() {
return "Short description";
}
}
Nevermind, I worked out the issue...
Change code from to...
//FROM
response.setContentType("text/html;charset=UF-8");
//TO
response.setContentType("text/html");
I'm Implementing a geoserver's OWS. I want to a specific method of the OWS get a ModelAndView as following:
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.servlet.ModelAndView;
public class HelloWorld {
public HelloWorld() {
// Do nothing
}
public ModelAndView sayHello(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException, Exception {
ModelAndView m = new ModelAndView("index");
return m;
}
}
How can I do this?
I have a Java servlet and entity manager factory
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
try (PrintWriter out = response.getWriter()) {
this.setLevels(request);
if i use the line, then servlet does not work
//this.emf = Persistence.createEntityManagerFactory("projectPU");
servlet method continue...
out.println("this is a html content ....");
}
}
how to use Persistence.createEntityManagerFactory("projectPU") in servlet? Thanks.
Hej,
if you do not want to use any frameworks, as suggested above, you can do it for example like that:
I created a class called DataBroker, this is the class which contains the EntityManager and can persist entities or send queries againt the database.
import javax.persistence.EntityManager;
import javax.persistence.Persistence;
public class DataBroker<T> {
private EntityManager em;
public DataBroker() {
if(em == null) {
em = Persistence.createEntityManagerFactory("ProjectPU").createEntityManager();
}
}
public void saveInput(T t) {
em.merge(t);
}
}
And now, for example a PersonServlet:
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import de.professional_webworkx.database.DataBroker;
import de.professional_webworkx.model.Person;
#WebServlet(urlPatterns = {"/personServlet"})
public class PersonServlet extends HttpServlet {
/**
*
*/
private static final long serialVersionUID = 318982491390578805L;
private DataBroker<Person> dataBroker = new DataBroker<>();
public PersonServlet() {
super();
}
protected void processRequest(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// do something with the user input from the jsp file
}
#Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
processRequest(req, resp);
}
#Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
processRequest(req, resp);
}
}
But it's right, these frameworks handle all this for you and you can be focused on your business logic or what else ;)
Patrick
I just starting learning about servlets yersterday so I'm a newbie. I read a tutorial and made the following program to track the use of a link:
package red;
import java.io.IOException;
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("/Redirection")
public class Redirection extends HttpServlet {
private static final long serialVersionUID = 1L;
private String referrer;
private String target;
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
try {
getURLs(request);
}
catch(Exception e)
{
response.sendError(500, "Target parameter not specified");
return;
}
response.sendRedirect(target);
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doGet(request, response);
}
public void getURLs(HttpServletRequest request)
{
referrer = request.getParameter("referrer");
if(referrer == null || 0 == referrer.length())
{
referrer = new String("");
}
target = request.getParameter("target");
if(target == null || target.equals(""))
{
throw new IllegalArgumentException();
}
}
}
But when I teste it(Eclipse with Tomcat) i get this:
HTTP Status 500 - Target parameter not specified
How do I specify a target parameter in eclipse so I can run this program ?
Sorry for the beginner question.
Well you don't really know what's going on here. Maybe you're getting a different exception - you're giving that error message whatever goes wrong. You should log exactly what's being thrown. You also shouldn't generally catch Exception yourself - catch more specific exceptions.
Anyway, normally to include that sort of parameter, you'd just put it in the URL:
/Redirect?target=x&referrer=y