I have two servlets 'ExtensionServlet' and 'PatternServlet' and a static html page. The HTML code is given below.
<html>
<head>
<title>
Resolve servlet ambiguity
</title>
</head>
<body>
<form action="servlets/form.col" method="POST">
<input type="submit" value="Goto Servlet">
</form>
</body>
</html>
The Deployment descriptor is as follows.
<?xml version="1.0" encoding="ISO-8859-1" ?>
<web-app version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd" >
<servlet>
<servlet-name>Extension Servlet</servlet-name>
<servlet-class>ExtensionServlet</servlet-class>
<servlet-name>Pattern Servlet</servlet-name>
<servlet-class>PatternServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Extension Servlet</servlet-name>
<url-pattern>*.col</url-pattern>
<servlet-name>Pattern Servlet</servlet-name>
<url-pattern>/servlets/*</url-pattern>
</servlet-mapping>
</web-app>
When I click the button in the HTML page it leads to "PatternServlet". If I rearrange the servlet order in the deployment descriptor as below, it goes to "ExtensionServlet"
<?xml version="1.0" encoding="ISO-8859-1" ?>
<web-app version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd" >
<servlet>
<servlet-name>Pattern Servlet</servlet-name>
<servlet-class>PatternServlet</servlet-class>
<servlet-name>Extension Servlet</servlet-name>
<servlet-class>ExtensionServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Pattern Servlet</servlet-name>
<url-pattern>/servlets/*</url-pattern>
<servlet-name>Extension Servlet</servlet-name>
<url-pattern>*.col</url-pattern>
</servlet-mapping>
</web-app>
Can anyone please explain this behavior?
Tomcat 6.0.20
JVM 1.6.0_15-b03
Is your schema a shortening of the following?
<?xml version="1.0" encoding="ISO-8859-1" ?>
<web-app version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd" >
<servlet>
<servlet-name>Pattern Servlet</servlet-name>
<servlet-class>PatternServlet</servlet-class>
</servlet>
<servlet>
<servlet-name>Extension Servlet</servlet-name>
<servlet-class>ExtensionServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Pattern Servlet</servlet-name>
<url-pattern>/servlets/*</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>Extension Servlet</servlet-name>
<url-pattern>*.col</url-pattern>
</servlet-mapping>
</web-app>
In your version I think you are defining only one servlet.
When tomcat encounters several definitions that match a request (like in your case), it uses the first one.
When Tomcat receives a request, it selects one single servlet for execution using the configured servlet mappings. If the requested URL matches more than one mapping, the best match is selected, ignoring the others.
By specification, path-prefix pattern mappings are preferred over extenstion mappings. This means that, in your example, the mapping on "/servlets/" should win over the one on ".col", and the request should always cause the execution of Pattern servlet. The unexpected behaviour you have when you rearrange the declarations is because your descriptor is not correct, as already pointed out by other answers. Try using a correct descriptor, like the one suggested by David Rabinowitz.
That doesn't look like a legal deployment descriptor to me. Doesn't the schema require something like this:
<servlet>
<servlet-name>Extension Servlet</servlet-name>
<servlet-class>ExtensionServlet</servlet-class>
</servlet>
<servlet>
<servlet-name>Pattern Servlet</servlet-name>
<servlet-class>PatternServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Extension Servlet</servlet-name>
<url-pattern>*.col</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>Pattern Servlet</servlet-name>
<url-pattern>/servlets/*</url-pattern>
</servlet-mapping>
Related
I have 3 servlets in my web application.
The first servlet is workinh OK.
The second and third servlet which is copying from the first one, doesn't work and doesn't get response.
However, I search on internet and all websites say: the error in web.xml file
This is my web.xml file:
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.1">
<servlet>
<servlet-name>getmarks</servlet-name>
<servlet-class>getmarks</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet>
<servlet-name>Login</servlet-name>
<servlet-class>Login</servlet-class>
<load-on-startup>2</load-on-startup>
</servlet>
<servlet>
<servlet-name>Enter</servlet-name>
<servlet-class>Enter</servlet-class>
<load-on-startup>3</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>getmarks</servlet-name>
<url-pattern>/getmarks</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>Login</servlet-name>
<url-pattern>/Login</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>Enter</servlet-name>
<url-pattern>/Enter</url-pattern>
</servlet-mapping>
<session-config>
<session-timeout>
30
</session-timeout>
</session-config>
Try This Code Web.xml file
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
<display-name>Your Project Name</display-name>
<servlet>
<servlet-name>ABC</servlet-name>
<servlet-class>getmarks</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet>
<servlet-name>DEF</servlet-name>
<servlet-class>Login</servlet-class>
<load-on-startup>2</load-on-startup>
</servlet>
<servlet>
<servlet-name>GHI</servlet-name>
<servlet-class>Enter</servlet-class>
<load-on-startup>3</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>ABC</servlet-name>
<url-pattern>/getmarks_1</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>DEF</servlet-name>
<url-pattern>/Login_1</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>GHI</servlet-name>
<url-pattern>/Enter_1</url-pattern>
</servlet-mapping>
<session-config>
<session-timeout>
30
</session-timeout>
</session-config>
</web-app>
You should put full class names in the <servlet-class> tag.
Also, <web-app> tag is missing some attributes about XML Schema. You can find more information here.
For version 3.1 it should look like this:
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
version="3.1">
// your mappings
</web-app>
Closing </web-app> tag is also missing.
I am developing JAVA web project by using netbeans IDE, I want to display some images from a folder outside the project's directory, after uploading them by my servlets, here is my code:
web.xml:
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.1" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd">
<session-config>
<session-timeout>
30
</session-timeout>
</session-config>
<welcome-file-list>
<welcome-file>views/index.jsp</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>login</servlet-name>
<servlet-class>controllers.LoginController</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>login</servlet-name>
<url-pattern>/login</url-pattern>
</servlet-mapping>
<servlet>
<servlet-name>index</servlet-name>
<jsp-file>/views/index.jsp</jsp-file>
</servlet>
<servlet-mapping>
<servlet-name>index</servlet-name>
<url-pattern>/index</url-pattern>
</servlet-mapping>
<servlet>
<servlet-name>students</servlet-name>
<servlet-class>controllers.StudentController</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>students</servlet-name>
<url-pattern>/students</url-pattern>
</servlet-mapping>
<servlet>
<servlet-name>books</servlet-name>
<servlet-class>controllers.BookController</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>books</servlet-name>
<url-pattern>/books</url-pattern>
</servlet-mapping>
<servlet>
<servlet-name>admins</servlet-name>
<servlet-class>controllers.AdminController</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>admins</servlet-name>
<url-pattern>/admins</url-pattern>
</servlet-mapping>
<context-param>
<param-name>uploads</param-name>
<param-value>C:/Users/mohammad/Documents/NetBeansProjects/uploads</param-value>
</context-param>
</web-app>
img in the jsp:
<img src="C:/Users/mohammad/Documents/NetBeansProjects/uploads/name.jpg"/>
servlet:
I am sending it inside a json object:
object.add("<img src=\""+getServletContext().getInitParameter("uploads")+"/"+book.getImage()+"\"/>");
I am sure that the image is exist in that folder, but it couldn't loaded, what is the problem here?
You should add filter on web.XML file of image extensions that actually specify that what kind of external resources can be passed through front controller.. Will u please post your web.xml
U may try this link Upload an image to a Path set in web.xml using primefaces
This question already has answers here:
Servlet returns "HTTP Status 404 The requested resource (/servlet) is not available"
(19 answers)
Closed 5 years ago.
The xml file is located in WebContent/WEB-INF/web.xml of my project. I am using Eclipse and running Tomcat (which is not installed via Eclipse. I prefer it to be a separate installation).
<?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" 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>EmployeeManagement</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>
<context-param>
<param-name>name</param-name>
<param-value>Pramod</param-value>
</context-param>
<servlet-mapping>
<servlet-name>Registration</servlet-name>
<url-pattern>/EmployeeManagement/WebContent/Registration</url-pattern>
</servlet-mapping>
</web-app>
It doesnt work when the form page submits to the servlet. I am getting a 404 error everytime. I have been encountering this problem for a while. Somebody please help me.
You are missing <servlet>...</servlet> tag which is important to mapping. So use 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" 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>EmployeeManagement</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>
<context-param>
<param-name>name</param-name>
<param-value>Pramod</param-value>
</context-param>
<servlet>
<servlet-name>Registration</servlet-name>
<servlet-class>com.yourPackageName.yourServletName</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Registration</servlet-name>
<url-pattern>/EmployeeManagement/WebContent/Registration</url-pattern>
</servlet-mapping>
</web-app>
and you should give action value on your form like following:
<form action="/EmployeeManagement/WebContent/Registration" method="post">
//Some code here
</form>
and also note it down all values are case sensitive on the following code:
<servlet>
<servlet-name>Registration</servlet-name>
<servlet-class>com.yourPackageName.yourServletName</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Registration</servlet-name>
<url-pattern>/EmployeeManagement/WebContent/Registration</url-pattern>
</servlet-mapping>
Your servlet name Registration should be same on both tags <servlet>...</servlet> and <servlet-mapping>...</servlet-mapping> and also package name should be same where your servlet class is located.
you have not mapped servlet name to servlet class, It should be like given below,
In <servlet-class> give the path of your servlet
<servlet>
<servlet-name>Registration</servlet-name>
<servlet-class>com.Registration<servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Registration</servlet-name>
<url-pattern>/EmployeeManagement/WebContent/Registration</url-pattern>
</servlet-mapping>
Check your form action.
Is the path there
/EmployeeManagement/WebContent/Registration
or
YOURAPPCONTEXT/EmployeeManagement/WebContent/Registration
or
YOURAPPNAME/EmployeeManagement/WebContent/Registration
You have specifyed a servlet-mapping and used the name Registration in servlet-name without defining it before.
You need to define the servlet before using it in a servlet mapping
<servlet>
<servlet-name>Registration</servlet-name>
<servlet-class>[fully qualifyied name of your servlet]</servlet-class>
</servlet>
You are missing another part to define the servlet in the web.xml
<servlet>
<servlet-name>Registration</servlet-name>
<servlet-class>
package.path.to.RegistrationServlet
</servlet-class>
</servlet>
You forgot a vital part of the configuration. You should add this to your web.xml before servlet-mapping tag:
<servlet>
<servlet-name>Registration</servlet-name>
<servlet-class>com.name.of.your.servlet.class</servlet-class>
</servlet>
This question already has answers here:
Servlet returns "HTTP Status 404 The requested resource (/servlet) is not available"
(19 answers)
Closed 5 years ago.
The xml file is located in WebContent/WEB-INF/web.xml of my project. I am using Eclipse and running Tomcat (which is not installed via Eclipse. I prefer it to be a separate installation).
<?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" 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>EmployeeManagement</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>
<context-param>
<param-name>name</param-name>
<param-value>Pramod</param-value>
</context-param>
<servlet-mapping>
<servlet-name>Registration</servlet-name>
<url-pattern>/EmployeeManagement/WebContent/Registration</url-pattern>
</servlet-mapping>
</web-app>
It doesnt work when the form page submits to the servlet. I am getting a 404 error everytime. I have been encountering this problem for a while. Somebody please help me.
You are missing <servlet>...</servlet> tag which is important to mapping. So use 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" 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>EmployeeManagement</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>
<context-param>
<param-name>name</param-name>
<param-value>Pramod</param-value>
</context-param>
<servlet>
<servlet-name>Registration</servlet-name>
<servlet-class>com.yourPackageName.yourServletName</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Registration</servlet-name>
<url-pattern>/EmployeeManagement/WebContent/Registration</url-pattern>
</servlet-mapping>
</web-app>
and you should give action value on your form like following:
<form action="/EmployeeManagement/WebContent/Registration" method="post">
//Some code here
</form>
and also note it down all values are case sensitive on the following code:
<servlet>
<servlet-name>Registration</servlet-name>
<servlet-class>com.yourPackageName.yourServletName</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Registration</servlet-name>
<url-pattern>/EmployeeManagement/WebContent/Registration</url-pattern>
</servlet-mapping>
Your servlet name Registration should be same on both tags <servlet>...</servlet> and <servlet-mapping>...</servlet-mapping> and also package name should be same where your servlet class is located.
you have not mapped servlet name to servlet class, It should be like given below,
In <servlet-class> give the path of your servlet
<servlet>
<servlet-name>Registration</servlet-name>
<servlet-class>com.Registration<servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Registration</servlet-name>
<url-pattern>/EmployeeManagement/WebContent/Registration</url-pattern>
</servlet-mapping>
Check your form action.
Is the path there
/EmployeeManagement/WebContent/Registration
or
YOURAPPCONTEXT/EmployeeManagement/WebContent/Registration
or
YOURAPPNAME/EmployeeManagement/WebContent/Registration
You have specifyed a servlet-mapping and used the name Registration in servlet-name without defining it before.
You need to define the servlet before using it in a servlet mapping
<servlet>
<servlet-name>Registration</servlet-name>
<servlet-class>[fully qualifyied name of your servlet]</servlet-class>
</servlet>
You are missing another part to define the servlet in the web.xml
<servlet>
<servlet-name>Registration</servlet-name>
<servlet-class>
package.path.to.RegistrationServlet
</servlet-class>
</servlet>
You forgot a vital part of the configuration. You should add this to your web.xml before servlet-mapping tag:
<servlet>
<servlet-name>Registration</servlet-name>
<servlet-class>com.name.of.your.servlet.class</servlet-class>
</servlet>
This is the follow up of this question how to remove .py from the url in jython , I couldnt get it solved till now, and hope to get some more suggestions for it.
Here is my web.xml file:
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd" >
<servlet>
<servlet-name>PyServlet</servlet-name>
<servlet-class>org.python.util.PyServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>PyServlet</servlet-name>
<url-pattern>/*</url-pattern>
</servlet-mapping>
<servlet>
<servlet-name>NewJythonServlet</servlet-name>
<servlet-class>NewJythonServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>NewJythonServlet</servlet-name>
<url-pattern>/NewJythonServlet</url-pattern>
</servlet-mapping>
</web-app>
any ideas please?
Try:
<servlet-mapping>
<servlet-name>PyServlet</servlet-name>
<url-pattern>/serv/*</url-pattern>
</servlet-mapping>
I think the url had to start with something that isn't a wildcard