Servlets :: Null Retrieved From Env-entry Resource
Jan 9, 2009
I have an env-entry defined in my web.xml and when I attempt to print it from a simple servlet all I get is null. And of course if I attempt to invoke any methods on the object I get a NullPointerException.I read somewhere that this can happen if you're using version 2.4 instead of 2.5, so I changed to 2.5 and I still have the same issue. Here's the web.xml:
I want to retrieve file from database which is stored with blob datatype and i am passing manually id associated with in code. Its not retrieving the file.
public class retrieve_image extends HttpServlet { /** * */ private static final long serialVersionUID = 1L; protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { ResultSet rs = null;
I configured a connection pool in tomcat 7. For every database activity I get a connection from the pool. Do I have to close the connection like other regular connection after the database operation is done? If I close the connection will it have any effect on the connection pool?
I am trying to use hidden variable in project.When I launch my project i am able to get the welcome page.But when submit login values i am getting HTTP 404 error- Resource not found error.
I mentioned the url-pattern in web.xml correctly and i also checked whether all the class files are present or not. But I am still getting ResourceNotFoundRException.
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859
So I have a screen I click on. The "webPage" comes back as the requested resource unavailable.
What I don't get is that when I run the server locally on my machine it works just fine. But when this is deployed out to server I get the error. The screen comes up but the data doesn't show up. Where should I look to troubleshoot this?
I have a link with URL say "/atom/filename.link" on one webpage on my server. On clicking it, a response will return in XML format.
In the XML there is information like:
<library id = "123" path =""/> <document id = "1234" path =""/>
With this information I can generate a URL to another link, say /libray?id=123/document?id=1234
Now I would like to realize a function so that on clicking this link, it will be automatically redirected to that new link, which is generated from the XML file.
At first I try to use a servlet/filter in a web-app and then deploy it on the server, inside this servlet/filter I make a new URL connection with the same request URL and retrieve the response and the parse the XML data. But now the request URL points to the servlet now, not the actual XML file.
For example, if I set the set the servlet-mapping to /atom, If I try to connect to the URL /atom/filename.link inside the servlet, will it still be directed to this servlet? It's like a loop, and the real content can never be reached because now the servlet occupies its path.
I use this code in Restlet Representation. I try to get the value from the Request API. But I am facing the problem as "Cannot make a static reference to the non-static method getQuery() from the type Resource".
I'm a new Java user and I'm trying to code a simple login page. In first page (NewFile.jsp) users should enter their username and password and should click on "login", or click on "sign up".
1.) If user enters his username and password correctly, a login page (LoginPage.jsp) appears and says "welcome null" but it should show the name of that user instead of null.
2.) In that login page there is an edit button to edit profile information. When I clicked on it, every information is "null" and when I edit them and click on "Submit" button;
HTTP Status 404 - type Status report message description The requested resource () is not available. GlassFish Server Open Source Edition 3.1.2
that message appears.
3.) If I click on "Sign Up" button at the beginning, a registration jsp (SignUpPage.jsp) appears. After filling up text boxes and clicking on "Submit", same Status 404 screen appears.
I created a mysql database called "loginpage" using xampp. In that database there is a table called "users" and it has un, pass, name, surname, email and degree attributes.
It works in the first time. But, after sometime the data is not retrieved and display empty screen. Once, i stop and start the server again, the data is getting retrieved again. But, later when we refresh the empty page is getting displayed again.
How to do this editing the last 3 letters of a string that i retrieve from database.. I have a string "111-222-333-000" here's the sample what i want to happen was to edit the last 3 letters of the string ,,
i insert into database "111-222-333-000" then i retrieve it for editing but what i want to happen is when i retrieve it what i can only edit was the last 3 strings only
It works in the first time. But, after sometime the data is not retrieved and display empty screen. Once, i stop and start the server again, the data is getting retrieved again. But, later when we refresh the empty page is getting displayed again.
I'd like to know is there a way to restrict a user from inputting certain characters into a TextField? Is there something like isNumeric() available?
In Visual Basic, I was able to prevent the user entering certain characters of my choice into each textbox, however I've looked and I haven't been able to find a solution. I've tried using the following else if as part of an if statement:
else if (txtEmployeeName.getText().contains("[0-9]+"){ }
I'm using Ubuntu. After unpacking the tar file for JSE 1.7 version 45, in the the bin directory for adding an entry to PATH variable, I typed
javac
and I get the message
The program 'javac' can be found in the following packages: * default-jdk * ecj * gcj-4.6-jdk * gcj-4.7-jdk * openjdk-7-jdk * openjdk-6-jdk Try: sudo apt-get install <selected package>
If I get the bytecode with javap it seems to work:
Java Code:
Exception Table from to target type 26 30 40 any mh_sh_highlight_all('java');
But the problem is that I can't run the file anymore. Simply running it with the java command results in "java.lang.VerifyError: Expecting a stackmap frame at branch target 40". After some research this seems to be a problem with java 7 and a stricter verifier. I read several times that java -XX:-UseSplitVerifier should be used instead.
This really fixed the stackmap error, but then another error appeared: "java.lang.VerifyError: (class: AClass, method: signature: ()V) Inconsistent stack height 2 != 1". Are there any further steps required to insert a new exception in the exception table?
Additional info: Later I want to remove gotos (in this case the goto at line 27) and add a function call instead. When this function finishes it will throw a exception and propagate it back to the caller (which will be at line 27). Then the program should go on as if nothing happend, that is also the reason why the target of the exception is the same as the target of the goto (40)
public class Test { public static void main(String[] args) { Car c = new Car(); c.setInf("toyota", "red"); System.out.println("name: "+ c.brand + " colour: " + c.colour);
[code]....
Why do I get the result brand null, colour null? I know what null means but what am I missing here?
and the corresponding snippets of the Java code are:
// Class member variables // ... private String product; private ArrayList<String> productValues; private ArrayList<String> productLabels; private SelectItem[] products; // ... Various properties etc. public String getLocation() { // Displayed on a page
[code]....
Most of this works correctly using only ArrayList SelectItem products without the two ArrayList and the separate SelectItem[], and the values and labels are put directly into products here. The menu works and I can select an item. However, I am unable to find the correct method for finding the index in the submit method,namely:
public void submit(ActionEvent e) { showProduct = true; prodNum = products.indexOf(product); // --- Here is the problem! updateProduct(); }
which has not been changed here. In spite of trying out various ideas, prodNum always returns with -1, which means it cannot find the index of the selected product, where product is a String. Everything else seems to work correctly, and products.get(prodNum).getLabel() works if I manually give prodNum a valid index, but because it's -1 it fails.
Is it possible to launch windows, specifically 8.1, directly into a java based program which would serve as the password entry screen? That is to say, instead of using the standard windows screen, could a java based alternative be used?
I have the source code used on jurassicsystems.com. I would absolutely kill to have a tweaked version of this system act as my password entry screen. It is literally something Ive wanted to have done for ages, and this emulation finally means it may be possible.
I have a list of 100,000 + names and I need to append to that list another 100,000 names. Each name must be unique. Currently I iterate through the entire list to be sure the name does not exist. As you can imagine this is very slow. I am new to Java and I am maintaining a 15+ year old product. Is there a better way to check for an existing name?
I have inherited some code that is supposed to work just fine. The trouble is that when everything is rebuilt on my desktop, the projects crash. They all seem to crash at one particular part of code. I pass it a string and the "getResource" or "getContentClassLoader" is failing.
[URL] ....
I guess one way to tackle this is to break it apart into segments.
