why use<bean:include instead of <jsp:include in struts?
from the documentation for bean:include
Perform an internal dispatch to the specified application component (or external URL) and make the response data from that request available as a bean of type String. This tag has a function similar to that of the standard jsp:include tag, except that the response data is stored in a page scope attribute instead of being written to the output stream. If the current request is part of a session, the generated request for the include will also include the session identifier (and thus be part of the same session).
first hit on google
bean:include works almost like jsp:include except that the result is stored in the page scope. This means that your code on the current page can access the results and manipulate it. See this page.
Related
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)
We have a form with 2 input fields.
These allow a user to type in destinations to plan a flight.
We want to use an external servlet that allows us to use autocompletion on the fields
(e.g. type "LO" and it gets the matches for that - London Heathrow would be at the top)
The servlet can be found at a URL like this: http://www.companyname.com/servlet/ac.json?n=12&q=LO
with "n" being the amount of results it should return, and "q" being the query.
How do I call that servlet from my HTML form, everytime the input field changes?
The servlet is on a different domain than my page, and I have absolutely no other access than calling it with the URL I posted.
The response from the servlet will always be a JSON string like this:
[{"type":"airport","city":"Cape Town","airport":"International","iata":"CPT","country":"South Africa","locationId":"airport_CPT"},
{"type":"city","city":"Chicago, IL","airport":"All Airports","iata":"CHI","country":"United States","locationId":"US_city_CHI"},
{"type":"airport","city":"Victoria","airport":"CA","iata":"YYJ","country":"Canada","locationId":"airport_YYJ"}]
How do I call that servlet from my HTML form, everytime the input field changes?
I strongly belive ,you need AJAX for this.If you use a normal servlet and use a form to submit each time the page will reload.
And coming to same servlet part,
You can specify the method names in AJAX request
You can try with JSP page in place of Servlet. You can call it very easily and it will complete your purpose also. Otherwise AJAX is best for this type of problem.
I have an jsp/servlet webapp on tompcat and i need something like a crash report each time an unexpected error accords
I have an error page defined and added with errorpage directive
<%#page errorPage="./erropage.jsp" %>
to my edit.jsp file(just an example).
The request to edit.jsp is made with post request (actually is an ajax request but this is not so important).
I need a solution to read original parameters (sent to edit.jsp page) from errorpage in order to buid a crash report.
request.getAttribute("javax.servlet.error.request_uri")
Doed not help me since this will include the actual url (get parameters).
Also, to build up a string from requested parameters in edit.jsp and set that string to session is not an option since there are to many files in witch i need to implement this.
Actually it seams like
request.getParamter()
in errorpage.jsp give the parameter from edit.jsp request!
I have a similar issue with cookies and I post a question about it.
Now, I believe ( I have some checks to do) that the error mechanism is using REDIRECT scheme (not FORWARD) so a new request object is created.. You can verify this assumption
I want to pass parameters from one jsp to another.
I have tried using the post method, <jsp:forward/>, but it doesn't work.
I have created a <form> in html (parameters passed using POST), which is submitted to a servlet which processes the request and forwards it to another servlet that displays a page.
From this servlet i have created links to another jsp, passing through the parameters as GETs in the URL. However, I actually want to pass the parameters to another jsp using POST, and then pass it on to another jsp.
What solutions do you have or this problem?
Check out the Request Dispatcher. You need to forward the request to the landing JSP.
http://docs.oracle.com/javaee/6/api/javax/servlet/RequestDispatcher.html
Sounds like you are creating a multipage form that gathers information from the user across several distinct pages. In that case one option is to use hidden fields on a form to store the previous values. This of course means that as the pages progress the amount of data passing back and forth from client to server increases.
You may consider a server side approach by storing the interim values in a database for instance, then only passing a token back to the client. When the next JSP page is submitted, use the token to look up the values in the database.
JSP has built-in request object.when one jsp redirect to another jsp with some parameter, you can get parameter value using this request object.
<%
String param1 = request.getParameter("parameter_name");
%>
you can find example here -
http://www.roseindia.net/jsp/RequestObjectInJSP.shtml
Why don't you call a page on the click of a submit button by creating
an url in the below format (in javascript):- var
url="your_page_name.jsp?value1="+encodeURIComponent(document.getElementById("your_text_field_or_any_other_field_id"));
and then call the page by using your url
document.your_form_name.action=url;
document.your_form_name.submit();
and then use request.getParameter() method either in servlet
or in the jsp that u'v metioned in the url (servlet or the jsp u'll be
calling thorugh u'r jsp).
I'm using netbeans to create a web application that allows a cell phone user to scan a QR code and retrieve a journal's previous/next title information. The take home point is that there's no form that the user will input data into. The QR code will contain the search string at the end of the URL and I want the search to start on page load and output a page with the search results. For now (due to simplicity), my model is simply parsing an XML file of a small sample of MARC records. Oh, to top it off...I'm brand new to programming in java and using netbeans. I have no clue about what javabeans are, or any of the more advance techniques. So, with that background explanation here's my question.
I have created a java class (main method) that parses my xml and retrieves the results correctly. I have an index.jsp with my html in it. Within the index.jsp, I have no problem using get to get the title information from my URL. But I have no clue how I would get those parameters to a servlet that contains my java code. If I manage to get the search string to the servlet, then I have no idea how to send that data back to the index.jsp to display in the browser.
So far every example I've seen has assumed you're getting form data, but I need parameters found, processed and returned on page load...IOW, with no user input.
Thanks for any advice.
Ceci
Just put the necessary preprocessing code in doGet() method of the servlet:
String foo = request.getParameter("foo");
// ...
request.getRequestDispatcher("/WEB-INF/page.jsp").forward(request, response);
And call the URL of the servlet instead of the JSP one e.g. http://example.com/page?foo=bar instead of http://example.com/page.jsp?foo=bar in combination with a servlet mapping on an URL pattern of /page/*.
You can get the url parameter in servlet using request.getParameter("paramName");
and you can pass the attribute to page from servlet using forwarding request from servlet to jsp.
See Also
Servlet wiki page
Bear in mind that your JSP page will compile internally to a servlet. So you can retrieve the string and print it back in the same JSP. For instance assuming you get the string in a parameter called param you would have something like this in your JSP:
<%
String param = request.getParameter( "param" );
out.println( "String passed in was " + param );
%>
One last thing, you mentioned the main method -- that only gets executed for stand alone applications -- whereas you're talking web/JSP :O