I'm playing arround with JSP and Servlets and have the following problem:
I have a JSP which implements something like a small "Login-Function". The code is the following:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!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=UTF-8">
</head>
<body>
Enter username and password:<br />
<hr />
<form method="GET" name="login" action="LoginCheck">
username<br />
<input type="text" name="loginName" /><br />
Password<br />
<input type="password" name="password" /><br />
<input type="submit" value="login" />
<input type="reset" value="reset" />
</form>
</body>
</html>
As you can see i want to access the servlet LoginCheck. The code is the following:
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class LoginCheck extends HttpServlet {
private static final long serialVersionUID = 1L;
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
response.setContentType("text/html");
PrintWriter out = response.getWriter();
String loginName = request.getParameter("loginName");
String password = request.getParameter("password");
if(loginName.equals("admin"))
{
if(password.equals("test"))
{
out.println("Username and password are correct!");
}else
{
out.println("Password were are incorrect!<br />");
out.println("<a href='index.jsp'>Here</a> you can get back to the Loginpage!");
}
}else
{
out.println("Username doesn't exist.<br />");
out.println("<a href='index.jsp'>Here</a> you can get back to the Loginpage!");
}
}
}
If i use the code of the servlet in another JSP, everything works fine, but i am not able to access the servlet. The XML ist the following:
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web- app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<display-name>Servlet</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
</web-app>
The server is a Jetty Server and no, i'm not allowed tu use a Tomcat. The structure of my Project in Eclipse looks like this: http://imageshack.us/photo/my-images/204/eclipseo.png/
Can you tell me why i can't access the servlet?
Thanks!
Your <Servlet>
has to be added in web.xml. Eg
<servlet>
<servlet-name>builder</servlet-name>
<servlet-class>LoginCheck</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>builder</servlet-name>
<url-pattern>/*</url-pattern>
</servlet-mapping>
You need to declare the servlet and the servlet mapping on your web.xml
:
<servlet>
<servlet-name>ServletName</servlet-name>
<servlet-class>servlet.LoginCheck</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ServletName</servlet-name>
<url-pattern>*</url-pattern>
</servlet-mapping>
Also, If more than of your servlets share the common URL pattern, you must be careful about the order of their declaration in web.xml
For example: If you have two servlets named servlet1 and servlet2 and you want to invoke servlet1 on /something/something2
but mean while want to invoke servlet2 on /something/*
than servlet1 should be declared before servlet2 in web.xml otherwise servlet2 will be invoked on every url pattern starting with /something/
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