I have a JSP page which displays a success message on successful deletion of an item.
However, if the page is refreshed, I want the message to not be displayed. I tried all I could do but it just doesn't happen.
I am setting the attribute in a Struts 2 class in request scope. I am retrieving the same attribute in my JSP page using request.getattribute(). After the if statement, I am trying to set the same attribute to null. But the success message remains after refreshing the page which I don't want.
Please help!
If you refresh the page, (from the browser I assume) you are actually sending the same request to server again. Which means, it will execute whatever it executes, put again that attribute on request, and you will get it back in the JSP page.
If you want to avoid that, you should have a way to tell, on the server side, that the operation has been already executed in order not to put the attribute on the request( for example, if you insert something, always check before if is not inserted already, and if so, just don't put that attribute on the request).
Related
I have a search.jsp page that has some html content and a form. When the form is submitted, there is a servlet handle the form data and forward the results to the search.jsp page. However, the url in the browser after processing the form is changed to the servlet name:
http://localhost:8080/MyProject/SearchServlet
not the search.jsp page:
http://localhost:8080/MyProject/Search.jsp
How I can change the url to the search.jsp? In other words, I just want to refresh the search.jsp page to display the results in the same page. How I can do that?
You cannot do that by forwarding the request: you need to "tell" the browser to generate a new http request by using the response.sendRedirect() method.
Now the question is why do you want the url bar to display the name of the Jsp?
Hiding the real destination path is a desired feature when forwarding requests: users do not need to know the server side redirects (that's how they are also called) happening in your web app.
Think about it: to carry out its tasks a servlet potentially can forward the request a number of times before getting to the final destination: you don't want the url bar to change each and every single time.
Give a fancier name to your servlet like: "Search" rather than "SearchServlet" so that users will know they are on the search page of your web application and not in the "SearchServlet" page.
In addition to that, if you visit any professional website, you will hardly ever see the .jsp or .html or .php extension on the address bar. While that is not a requirement or specification and you are free to do so, I believe the first approach is best practice (it looks even better to me honestly). There is even a folder WEB-INF whose purpose is to hide your .jsp pages from direct access via url bar.
What I like doing is having a servlet as the landing-welcome page of the web app, that will be responsible to forward and redirect requests based on the user input and the inner working of the application.
Now back to your final request (pun intended)
"In other words, I just want to refresh the search.jsp page to display the results in the same page. How I can do that?"
What I would do is:
redirect the user to the "Search" servlet from the welcome/home servlet.
In the doGet method of the Search servlet I would forward the request to the search.jsp page (you could set attributes before forwarding if you need to).
In the search.jsp I would set the action attribute of the form to "Search" (the name of the servlet) and the method to POST.
In the doPost method of the Search servlet you would implement whatever logic you wish to implement and finally forward the request to the search.jsp
After hitting the search button (and even after the submit button is clicked) what the user will see on the address bar is simply
http://localhost:8080/MyProject/Search
Hope that makes sense.
Are you using the same search.jsp for searching and well as showing the result? It is possible to use the same jsp to perform both the functions but it's easier and desirable to make another jsp which will only show the results.
If you are not able to see the results on search.jsp then make sure that you are setting the proper response in the Servlet class before forwarding it to the jsp and also whether you are reading the response sent by the Servlet class properly in the jsp.
If you want, the page to not refresh at all, then go for AJAX.
Hi I have jsp page That is having some text fields,I will fill that text fields and I will submit that form to server side.If any error comes in the server side I will redirect to the same page with error message Now I want that text field to remain as it is but in my case it is clearing.How to make the text field as same.
The two options available to you are:
Don't reload the page. Instead submit the data via AJAX or validate it by javascript. That way you don't ever have to touch the data in the form. Make sure your javascript highlights the fields that have errors in some way.
The endpoint that you're POSTing your data to needs to be able to recognise that the data is invalid and include that data when returning the user to the same page. I'm not familiar with jsp, but generally you'd do that by including variables in your template for your form that could contain the data, and passing empty strings on the first load of the page. If the page is then shown to the user again after a failed form validation, pass back the POST data that you received in your form request.
There are two option, you can dispatch the request/response to the same page instead of redirect, but you need to add an attribute and recover it in the JSP, or you can add the attribute in the session , recover the value to de text field and remove it using (if you are using JSTL)
Hi I have one jsp page and I have to update two html select boxes with the data of an inf file. On selecting the first combo(initially also not loading the second combo), the second will have to change accordingly. Since java script variable is not accessible from java, I had sent the value of first combo to an another jsp by ajax. And then return it to first jsp itself.Plaese help me.
Maybe I'm getting it wrong but looking at your code it seems that you are doing AJAX request on selectbox change event, but you are not doing anything with the response.
So basically what happens is you are doing an initial render to your jsp and everything is fine. Now you are changing selectbox option and AJAX request is sent to dummy.jsp. dummy.jsp is receiving it and redirecting the maker of the request to User.jsp. User.jsp-s content is sent back but nothing is done on the client side AJAX call with this response.
What you should do is have your logic at dummy.jsp(or even better at some servlet) which based on your AJAX call request parameters returns for example a JSON with data that you can process in jQuery.ajax success event. In there you can use this JSON to readjust your selectboxes and other data with javascript.
Check the examples at the end of jQuery.ajax manual: http://api.jquery.com/jquery.ajax/
I have a JSP page to search customers. This page calls the controller, which execute a method to return a list of customers and after forward to the origin URL;
I used to forward : request.getRequestDispatcher(urlOrigin).forward(request, response);
(note 1: request.getHeader("Referer") was used to get complete origin URL )
(note 2: There a method to split the complete origin URL and get name page )
Since it, I have the following url in the browsear :
(http://domain/ProjetoT/mvc)
Its the url of my controller
If I search a customer again won't work, because the controller url will be recognized as origin url.
I Tried use : response.Sendredirect(urlOrigin);
But I lost my object and the list of customers didn't rendered.
Anyone can help me please?
Thanks!
Instead of intially accessing the JSP page directly in the browser, you could access it through the same controller used to process the search. To do that you would have to program your controller to detect if you are in initial display mode or if you are in "submit" mode. This is typically done by checking the presence of a parameter that is sent in the submit.
So in initial display mode, your controller would just forward to the JSP without any further processing, while in submit mode it would do what it is currently doing. This way you would be using the same URL for both the initial display and the submit and the problem you described should go away (that is, if I understand your question correctly).
I want to forward from one page to another but with the same I want url to be changed. Suppose user is here http://mywebsite/register and when he completes his registration process then I want this in his address bar http://mywebsite/home
Is it possible without using sendRedirect , I mean by the way server side forwarding only? or any other way around to this problem?
You could just let the HTML form submit to that URL directly.
<form action="http://mywebsite/home">
But this makes no sense. You'll also run into problems when redisplaying the same form with validation messages in case of validation failure. You'd need to redirect back to the original page if you intend to keep the original URL and you'd need to fiddle with storing messages in the session scope instead of the request scope because a redirect basically creates a brand new request. You'll without a redirect also run in "double submit" problem whenever the enduser presses F5 after submitting the form.
Just let the servlet redirect the successful POST request to the desired URL. That's the canonical approach. Even more, this is a recommend "design pattern": the POST-Redirect-GET pattern.
AFAIK there's no way around a redirect since the browser has to update the url at some point. And if you'd update the url after the forwarded to page has been loaded it would issue a refresh and the page would be loaded again (which might result in an endless loop).
Why don't you want to use a redirect in that case?