Introduction To browse and select a file for upload you need a HTML <input type=”file”> field in the form. As stated in the HTML specification you have to use the POST method and the enctype attribute of the form has to be set to “multipart/form-data”. <form action=”upload” method=”post” enctype=”multipart/form-data”> <input type=”text” name=”description” /> <input type=”file” … Read more
When you clean and build under Netbeans, you should find all you need under the dist folder: if you a creating a web application you should find a .war file – that is the file to deploy: just copy it to the webapps folder for Tomcat if you are creating a standalone application or a … Read more
you can try this instead of System.out.print: PrintWriter out = response.getWriter(); out.print(smt);
You have given no HTML or any script you have tried yourself as such the below should serve as a good template for you to get started. DEMO – Cascading dropdowns, show managers for selected department Assuming the following HTML <div> <div style=”float: left;”> Select Department <br /> <select id=”departments”></select> </div> <div style=”float: left; margin-left: … Read more
First, when the user press a button , it is in the front end , not the back end ,so when the user press the button , it should invoke a request through the http protocol , when the server accept this request , it can call your java code ,but I don’t think you … Read more
I’d recommend you split the String in a separate step prior to the iteration. Also, validate that you really do receive the expected parameter from the HTTP request in the first place.
Could you try to construct the url little bit differently, as follows: <td><a href=<%= “\”ShowExam.jsp?Examid=” + ex.getV_exam_id() +”\”” %> ><%= ex.getV_exam_id()%> </a> </td> Note spaces near to <%= %> and how I give the quotation marks “\” and “\””. This should fix it if the rest of the code you did not provide is working … Read more
Clearly, the fact that leaving out the if cause a NullPointerException means that one or both of the comment or subject parameters is missing. That would suggest that the problem is in the form. Use your browser’s web developer capabilities to find out precisely what request is being sent to your server. It looks like … Read more