I guess, DAO is thread safe, does not use any class members. So can it be used without any problem as a private field of a Servlet ? We need only one copy, and multiple threads can access it simultaneously, so why bother creating a local variable, right? ...
I want to upload an Image using JSP Servlet and ejb 3.0 ...
I have created a hidden form element <form name="UploadImage" enctype="multipart/form-data" method="post" action="UploadImage"> <label> </label> <input name="imgUploadObjId" id="imgUploadObjId" value="52" type="hidden"> //rest of the form here </form> And I am trying to get the value with this line in a servlet (...
I use the following code to update an object from servlet in Google App Engine : String Time_Stamp=Get_Date_Format(6),query="select from "+Contact_Info_Entry.class.getName()+" where Contact_Id == '"+Contact_Id+"' order by Contact_Id desc"; PersistenceManager pm=null; try { pm=PMF.get().getPersistenceManager(); // note that this re...
I have an Excel file on the server side. How I can display it on client side browser using servlets? Thanks in advance. ...
I'm experimenting with EJB3 I would like to inject a stateful session bean into a servlet, so that each user that hits the servlet would obtain a new bean. Obviously, I can't let the bean be an instance variable for the servlet, as that will be shared. And apparantly injecting local variables isn't allowed. I can use the new operator...
I'm trying to figure out why my servlet code creates wave files with improper headers. I use: AudioSystem.write( new AudioInputStream( new ByteArrayInputStream(memoryBytes), new AudioFormat(22000, 16, 1, true,false), memoryBytes.length ), AudioFileFormat.Type.WAVE, servletOutputStream ); taking a byte array from memory contain...
I want to send an image from a J2ME client to a Servlet. I am able to get a byte array of the image and send it using HTTP POST. conn = (HttpConnection) Connector.open(url, Connector.READ_WRITE, true); conn.setRequestMethod(HttpConnection.POST); conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); os.write(byte...
Hi, I'm using java servlets and jsp in my application and I need to read the remote XML file and properly render it into HTML and display on a web page...What is the technology used for reading process?Should I use HTTPURLConnection class to read the contents of the xml file or there is some other way? And also,if I use servlet as a con...
Hello everyone, I have two servlets: LoginServlet and MailServlet. LoginServlet queries a mysql table using jdbc to get a string(eMail). What I want is to forward this string to MailServlet which in turn will send an email to that e-mail ID sent by LoginServlet. My question is how do I call and send the variable eMail to MailServlet, ...
Given an object X; I want this object to have an image. The image must be stored in the database. I can't store the path, the actual image must be in the database. My question can be answered by answering the following subquestions: a). What type of field should I put in the database? (e.g VARCHAR) b) What type of object should I use ...
I'm trying to read image from database with Ajax, but I could not read the xmlhttp.responseText to the img src. The image is saved as binary data in database and also retrieved as binary data. I'm using Ajax in JSP, because I want to give the user the ability to upload images and I will view the last uploaded image, on mouse over action ...
I have some code which reads a file through a form field of type file <input type="file" ... /> I want to give the user another option of providing a url to a file rather than having to upload it as many are already online. How can I detect when this field is empty on the server side. I am using Apache Commons FileUpload FileItemSt...
I get the exception: "URI scheme is not file" What I am doing is trying to get the name of a file and then save that file (from another server) onto my computer/server from within a servlet. I have a String called "url", from thereon here is my code: url = Streams.asString(stream); //gets the URL from a form on a webpage System.out.pr...
Hi, I am creating a cookie in a jsp script, which is located at: www.myproject.com/login/index.jsp if I restart the browser and navigate there, all works well, I can see the cookie persist. If I navigate to: www.myproject.com I am not seeing the cookie. Do I need to set something in the cookie path or domain to make the cookie vis...
I have a 3rd-party servlet that I cannot modify. It accepts an init-param that I would like to externalize (from web.xml). I can externalize a servlet filter init-param using DelegatingFilterProxy. This effectively moves the servlet filter definition into Spring where there are much more powerful externalization tools (eg: PropertyPlace...
Hi there, I'm refactoring a big piece of code atm where a long taking operation is executed in a servlet. Now sometimes I don't get a response after the operation has finished. (It has finished because it is printed into the logs) What I wish to achieve would some "fire and forget" behavior by the servlet. I would pass my params to the...
SEVERE: IOException while loading persisted sessions: java.io.WriteAbortedException: writing aborted; java.io.NotSerializableException: That means this object cannot be persisted on hard disk. Does it imply that it's not safe to keep in Session objects that do not implement "Serializable"? I haven't heard that ther...
For Jetty, Tomcat, or any other servlet container of your choice, what's the average footprint (memory, and any other notable resources) of a basic servlet? This includes any other basic objects that you almost always need per servlet, such as a view resolver. I'm not looking for a quantitative number in particular, but any indicative a...
I have a simple (Servlet, JSP, and JSTL) web app whose main functionality is displaying images retrieved from a back-end server. The controller servlet forwards the user to a JSP that in turn uses another Servlet to display the resulting image on that same JSP. Further down, the JSP has a line similar to: <a href="<c:out value='${imageU...