How to load servlet as first page in jsp application manage other servlets

Question

I wanted to load a servlet as the first page in my simple jsp appication. Therefore I added the servlet in this URL mapping.

<servlet>
    <servlet-name>StudentController</servlet-name>
    <servlet-class>com.stu.controller.StudentController</servlet-class>
</servlet>

<servlet-mapping>
    <servlet-name>StudentController</servlet-name>
    <url-pattern>/</url-pattern>
</servlet-mapping>

And this is the Get method of above mentioned servlet.

@Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        String path = request.getServletPath();
        if (path.equals("/addstudent")) {
            createStudent(request, response);
            ......
        else {
            searchAll(request, response);
        }
     }     

    protected void searchAll(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {
        List<StudentDTO> coList = null;
        coList = StudentDAO.searchStudentList();
        if (coList != null) {
           request.setAttribute("stulist", coList);
        } else {
           request.setAttribute("msg", "No Record Found.");
        }
        RequestDispatcher rd = request.getRequestDispatcher("home.jsp");
        rd.forward(request, response);
   }

This is working as predicted, but the problem is I tried to create another servlet called CourseController and I mapped it in web.xml

<servlet>
    <servlet-name>CourseController</servlet-name>
    <servlet-class>com.stu.controller.CourseController</servlet-class>
</servlet>
 <servlet-mapping>
    <servlet-name>CourseController</servlet-name>
    <url-pattern>/course/</url-pattern>
</servlet-mapping>

And the Get of the servlet is same as before.

@Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        String path = request.getServletPath();
        if (path.equals("/addcourse")) {
            createCourse(request, response);
            ......
     }

And I tried to access the servlet using an anchor tag in my home.jsp page.

<a href="${pageContext.request.contextPath}/newstudent">Create Student</a> 
<br/>
<a href="${pageContext.request.contextPath}/course/newcourse/">Create Course</a>

But I keep getting 404 error while trying to connect CourseController servlet.

This some how return to the searchAll method in StudentController servlet. I understand something is wrong with the mapping here. But I don't know what is that.

Please help. Thank you.

score 0 · Accepted Answer · answered Mar 12 '20 at 16:19

0

You need to configure unique url-patterns, so "/" cannot work if you have more than one servlet.

Assuming that your first servlet has url-pattern "/newstudent" you can configure it as welcome-file:

<welcome-file-list>
    <welcome-file>newstudent</welcome-file>
</welcome-file-list>

answered Mar 12 '20 at 16:19

Stefan

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I do not know what anchor tags are. – Stefan Mar 12 '20 at 16:40
Sorry, so how can I access those method in controller? like `newcourse`? – Dil. Mar 12 '20 at 16:43
I do not understand your question. You first asked about path mapping, now you wan to access a method. Which method do you want to access from where and why? – Stefan Mar 12 '20 at 16:52
So sorry my mistake. Thank you for your anwer. – Dil. Mar 12 '20 at 16:56
1

The correct answer is to replace `/` by ``. See the duplicates. – BalusC Mar 12 '20 at 19:25
@BalusC I tried that before and then I got 404 for both paths. – Dil. Mar 13 '20 at 03:10

How to load servlet as first page in jsp application manage other servlets

1 Answers1