Servlet doesn't find CSS [duplicate] - css

I'm having trouble with loading CSS and images and creating links to other pages when I have a servlet forward to a JSP. Specifically, when I set my <welcome-file> to index.jsp, the CSS is being loaded and my images are being displayed. However, if I set my <welcome-file> to HomeServlet which forwards control to index.jsp, the CSS is not being applied and my images are not being displayed.
My CSS file is in web/styles/default.css.
My images are in web/images/.
I'm linking to my CSS like so:
<link href="styles/default.css" rel="stylesheet" type="text/css" />
I'm displaying my images as follows:
<img src="images/image1.png" alt="Image1" />
How is this problem caused and how can I solve it?
Update 1: I've added the structure of the application, as well as some other information that might help.
The header.jsp file is the file that contains the link tag for the CSS. The HomeServlet is set as my welcome-file in web.xml:
<welcome-file-list>
<welcome-file>HomeServlet</welcome-file>
</welcome-file-list>
The servlet is declared and mapped as followes in the web.xml:
<servlet>
<servlet-name>HomeServlet</servlet-name>
<servlet-class>com.brianblog.frontend.HomeServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>HomeServlet</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
Update 2: I found the problem finally - my servlet was mapped incorrectly. Apparently when setting a Servlet as your <welcome-file> it can't have a URL pattern of /, which I find sort of weird, because wouldn't that stand for the root directory of the site?
The new mapping is as follows:
<servlet-mapping>
<servlet-name>HomeServlet</servlet-name>
<url-pattern>/HomeServlet</url-pattern>
</servlet-mapping>

All relative URLs in the HTML page generated by the JSP file are relative to the current request URL (the URL as you see in the browser address bar) and not to the location of the JSP file in the server side as you seem to expect. It's namely the webbrowser who has to download those resources individually by URL, not the webserver who has to include them from disk somehow.
Apart from changing the relative URLs to make them relative to the URL of the servlet instead of the location of the JSP file, another way to fix this problem is to make them relative to the domain root (i.e. start with a /). This way you don't need to worry about changing the relative paths once again when you change the URL of the servlet.
<head>
<link rel="stylesheet" href="/context/css/default.css" />
<script src="/context/js/default.js"></script>
</head>
<body>
<img src="/context/img/logo.png" />
link
<form action="/context/servlet"><input type="submit" /></form>
</body>
However, you would probably like not to hardcode the context path. Very reasonable. You can obtain the context path in EL by ${pageContext.request.contextPath}.
<head>
<link rel="stylesheet" href="${pageContext.request.contextPath}/css/default.css" />
<script src="${pageContext.request.contextPath}/js/default.js"></script>
</head>
<body>
<img src="${pageContext.request.contextPath}/img/logo.png" />
link
<form action="${pageContext.request.contextPath}/servlet"><input type="submit" /></form>
</body>
(which can easily be shortened by <c:set var="root" value="${pageContext.request.contextPath}" /> and used as ${root} elsewhere)
Or, if you don't fear unreadable XML and broken XML syntax highlighting, use JSTL <c:url>:
<head>
<link rel="stylesheet" href="<c:url value="/css/default.css" />" />
<script src="<c:url value="/js/default.js" />"></script>
</head>
<body>
<img src="<c:url value="/img/logo.png" />" />
link
<form action="<c:url value="/servlet" />"><input type="submit" /></form>
</body>
Either way, this is in turn pretty cumbersome if you have a lot of relative URLs. For that you can use the <base> tag. All relative URL's will instantly become relative to it. It has however to start with the scheme (http://, https://, etc). There's no neat way to obtain the base context path in plain EL, so we need a little help of JSTL here.
<%#taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%#taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %>
<c:set var="req" value="${pageContext.request}" />
<c:set var="uri" value="${req.requestURI}" />
<c:set var="url">${req.requestURL}</c:set>
...
<head>
<base href="${fn:substring(url, 0, fn:length(url) - fn:length(uri))}${req.contextPath}/" />
<link rel="stylesheet" href="css/default.css" />
<script src="js/default.js"></script>
</head>
<body>
<img src="img/logo.png" />
link
<form action="servlet"><input type="submit" /></form>
</body>
This has in turn (again) some caveats. Anchors (the #identifier URL's) will become relative to the base path as well! You would like to make it relative to the request URL (URI) instead. So, change like
jump
to
jump
Each way has its own pros and cons. It's up to you which to choose. At least, you should now understand how this problem is caused and how to solve it :)
See also:
Is it recommended to use the <base> html tag?

I faced similar issue with Spring MVC application. I used < mvc:resources > tag to resolve this issue.
Please find the following link having more details.
http://www.mkyong.com/spring-mvc/spring-mvc-how-to-include-js-or-css-files-in-a-jsp-page/

You must analyse the actual HTML output, for the hint.
By giving the path like this means "from current location", on the other hand if you start with a / that would mean "from the context".

Your welcome page is set as That Servlet . So all css , images path should be given relative to that servlet DIR . which is a bad idea ! why do you need the servlet as a home page ? set .jsp as index page and redirect to any page from there ?
are you trying to populate any fields from db is that why you are using servlet ?

If you are using Spring MVC, then you need to declare default action servlet for static contents. Add the following entries in spring-action-servlet.xml. It worked for me.
NOTE: keep all the static contents outside WEB-INF.
<!-- Enable annotation-based controllers using #Controller annotations -->
<bean id="annotationUrlMapping" class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping">
<property name="order" value="0" />
</bean>
<bean id="controllerClassNameHandlerMapping" class="org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping">
<property name="order" value="1" />
</bean>
<bean id="annotationMethodHandlerAdapter" class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"/>

As for your update, I was confused for the reasoning behind in. Dug a little deeper and found this gem:
yoursite.com becomes yoursite.com/
yoursite.com/ is a directory, so the welcome-file-list is scanned
yoursite.com/CMS is the first welcome-file ("CMS" in the welcome-file-list), and there is a mapping of /CMS to the MyCMS servlet, so that servlet is accessed.
Source: http://wiki.metawerx.net/wiki/HowToUseAServletAsYourMainWebPage
So, the mapping then does make sense.
And one can now freely use ${pageContext.request.contextPath}/path/ as src/href for relative links!

short answer - add following line in the jsp which will define the base
base href="/{root of your application}/"

Below code worked for me.
instead of
use
<%# include file="styles/default.css"%>

You can try out this one as well as. Because this worked for me and it's simple.
<style>
<%# include file="/css/style.css" %>
</style>

Related

What is diiference between Root Directory and Parent Directory in Jsp? [duplicate]

I'm having trouble with loading CSS and images and creating links to other pages when I have a servlet forward to a JSP. Specifically, when I set my <welcome-file> to index.jsp, the CSS is being loaded and my images are being displayed. However, if I set my <welcome-file> to HomeServlet which forwards control to index.jsp, the CSS is not being applied and my images are not being displayed.
My CSS file is in web/styles/default.css.
My images are in web/images/.
I'm linking to my CSS like so:
<link href="styles/default.css" rel="stylesheet" type="text/css" />
I'm displaying my images as follows:
<img src="images/image1.png" alt="Image1" />
How is this problem caused and how can I solve it?
Update 1: I've added the structure of the application, as well as some other information that might help.
The header.jsp file is the file that contains the link tag for the CSS. The HomeServlet is set as my welcome-file in web.xml:
<welcome-file-list>
<welcome-file>HomeServlet</welcome-file>
</welcome-file-list>
The servlet is declared and mapped as followes in the web.xml:
<servlet>
<servlet-name>HomeServlet</servlet-name>
<servlet-class>com.brianblog.frontend.HomeServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>HomeServlet</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
Update 2: I found the problem finally - my servlet was mapped incorrectly. Apparently when setting a Servlet as your <welcome-file> it can't have a URL pattern of /, which I find sort of weird, because wouldn't that stand for the root directory of the site?
The new mapping is as follows:
<servlet-mapping>
<servlet-name>HomeServlet</servlet-name>
<url-pattern>/HomeServlet</url-pattern>
</servlet-mapping>
All relative URLs in the HTML page generated by the JSP file are relative to the current request URL (the URL as you see in the browser address bar) and not to the location of the JSP file in the server side as you seem to expect. It's namely the webbrowser who has to download those resources individually by URL, not the webserver who has to include them from disk somehow.
Apart from changing the relative URLs to make them relative to the URL of the servlet instead of the location of the JSP file, another way to fix this problem is to make them relative to the domain root (i.e. start with a /). This way you don't need to worry about changing the relative paths once again when you change the URL of the servlet.
<head>
<link rel="stylesheet" href="/context/css/default.css" />
<script src="/context/js/default.js"></script>
</head>
<body>
<img src="/context/img/logo.png" />
link
<form action="/context/servlet"><input type="submit" /></form>
</body>
However, you would probably like not to hardcode the context path. Very reasonable. You can obtain the context path in EL by ${pageContext.request.contextPath}.
<head>
<link rel="stylesheet" href="${pageContext.request.contextPath}/css/default.css" />
<script src="${pageContext.request.contextPath}/js/default.js"></script>
</head>
<body>
<img src="${pageContext.request.contextPath}/img/logo.png" />
link
<form action="${pageContext.request.contextPath}/servlet"><input type="submit" /></form>
</body>
(which can easily be shortened by <c:set var="root" value="${pageContext.request.contextPath}" /> and used as ${root} elsewhere)
Or, if you don't fear unreadable XML and broken XML syntax highlighting, use JSTL <c:url>:
<head>
<link rel="stylesheet" href="<c:url value="/css/default.css" />" />
<script src="<c:url value="/js/default.js" />"></script>
</head>
<body>
<img src="<c:url value="/img/logo.png" />" />
link
<form action="<c:url value="/servlet" />"><input type="submit" /></form>
</body>
Either way, this is in turn pretty cumbersome if you have a lot of relative URLs. For that you can use the <base> tag. All relative URL's will instantly become relative to it. It has however to start with the scheme (http://, https://, etc). There's no neat way to obtain the base context path in plain EL, so we need a little help of JSTL here.
<%#taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%#taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %>
<c:set var="req" value="${pageContext.request}" />
<c:set var="uri" value="${req.requestURI}" />
<c:set var="url">${req.requestURL}</c:set>
...
<head>
<base href="${fn:substring(url, 0, fn:length(url) - fn:length(uri))}${req.contextPath}/" />
<link rel="stylesheet" href="css/default.css" />
<script src="js/default.js"></script>
</head>
<body>
<img src="img/logo.png" />
link
<form action="servlet"><input type="submit" /></form>
</body>
This has in turn (again) some caveats. Anchors (the #identifier URL's) will become relative to the base path as well! You would like to make it relative to the request URL (URI) instead. So, change like
jump
to
jump
Each way has its own pros and cons. It's up to you which to choose. At least, you should now understand how this problem is caused and how to solve it :)
See also:
Is it recommended to use the <base> html tag?
I faced similar issue with Spring MVC application. I used < mvc:resources > tag to resolve this issue.
Please find the following link having more details.
http://www.mkyong.com/spring-mvc/spring-mvc-how-to-include-js-or-css-files-in-a-jsp-page/
You must analyse the actual HTML output, for the hint.
By giving the path like this means "from current location", on the other hand if you start with a / that would mean "from the context".
Your welcome page is set as That Servlet . So all css , images path should be given relative to that servlet DIR . which is a bad idea ! why do you need the servlet as a home page ? set .jsp as index page and redirect to any page from there ?
are you trying to populate any fields from db is that why you are using servlet ?
If you are using Spring MVC, then you need to declare default action servlet for static contents. Add the following entries in spring-action-servlet.xml. It worked for me.
NOTE: keep all the static contents outside WEB-INF.
<!-- Enable annotation-based controllers using #Controller annotations -->
<bean id="annotationUrlMapping" class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping">
<property name="order" value="0" />
</bean>
<bean id="controllerClassNameHandlerMapping" class="org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping">
<property name="order" value="1" />
</bean>
<bean id="annotationMethodHandlerAdapter" class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"/>
As for your update, I was confused for the reasoning behind in. Dug a little deeper and found this gem:
yoursite.com becomes yoursite.com/
yoursite.com/ is a directory, so the welcome-file-list is scanned
yoursite.com/CMS is the first welcome-file ("CMS" in the welcome-file-list), and there is a mapping of /CMS to the MyCMS servlet, so that servlet is accessed.
Source: http://wiki.metawerx.net/wiki/HowToUseAServletAsYourMainWebPage
So, the mapping then does make sense.
And one can now freely use ${pageContext.request.contextPath}/path/ as src/href for relative links!
short answer - add following line in the jsp which will define the base
base href="/{root of your application}/"
Below code worked for me.
instead of
use
<%# include file="styles/default.css"%>
You can try out this one as well as. Because this worked for me and it's simple.
<style>
<%# include file="/css/style.css" %>
</style>

How to load CSS for different URL in spring MVC app

I have a problem loading css for different URL.
This is my current structure:
-webapp
|--resources
|---css
|---generalize.css
|---js
|---images
|--WEB-INF
|---views
|---login
|---dashboard
This is my spring configuration to look for the resources:
<mvc:resources mapping="/resources/**" location="/resources/" />
And in the jsp page, I try to load it as:
<link href="<c:url value="resources/css/generalize.css" />" rel="stylesheet" type="text/css" />
If I have an url like localhost:8888/myapp/login or localhost:8888/myapp/dashboard, the css will apply fine. But when I try to map the dashboard page with the url localhost:8888/myapp/user/dashboard, the page loses its css style. Would anyone help to explain how would be the correct way to load the css (or using the resources)?
I have tried to prepend the contextPath as below but it does not work as well.
<link href="<c:url value="${pageContext.request.contextPath}/resources/css/generalize.css" />" rel="stylesheet" type="text/css" />
Simply use context relative path by appending / in the beginning.
<c:url value="/resources/css/generalize.css" />
You don't need to append context path in the beginning.

Why does MVC automatically expand virtual URLs?

In my Layout.cshtml file I have the following line:
<link rel="stylesheet" href="~/Content/bootstrap.css" />
My assumption was that since I did not include Url.Content() call, it would actually just render what I wrote but not expand the virtual URL automatically. This assumption is wrong - the generated HTML does include the correct path to the file, not the virtual path I entered.
If I wrap the <link> in <script>
<script type="text/html">
<link rel="stylesheet" href="~/Content/bootstrap.css" />
</script>
then the URL is not expanded.
Which part of ASP.NET MVC does this automatic parsing of HTML and is there a way to control it?
This was a new feature included in Razor2 and ASP.NET MVC 4 and was designed to make life easier by not having to use Url.Content everywhere.
http://www.davidhayden.me/blog/asp.net-mvc-4-the-new-tilde-slash-feature-in-razor-2
The feature only works inside standard HTML attributes and that's why you don't get it inside your <script> tag or anywhere else.
You could use a simple output write to work around this:
<link rel="stylesheet" href="#("~/Content/bootstrap.css")" />

SpringRoo placing <script> and <link> on load-scripts.tagx from view.xml

A best practice of web development is to place the <styles> and <scripts> on a particular page in .css and .js file respectively.
This question might be a duplicate from this question and the answer from #java1337 get it working. From his answer file management can be an issue since for every definition of a view (.jspx) it is required to add another .jspx file containing all <link href> and <scripts src>.
One possible solution I'm working on is adding in the view.xml the URL/link of all .css and .js files that needed to be placed in the <head> section. Below is a sample of a view.xml is the structure I'm working on but I can get it working on the load-scripts.tagx
<definition extends="default" name="user/index">
<put-attribute name="body" value="/WEB-INF/views/user/index.jspx" />
<put-list-attribute name="scriptsList">
<add-attribute value="/resources/scripts/user/script.js"/>
</put-list-attribute>
</definition>
And on the load-scripts.tagx
<tiles:useAttribute id="list" name="scriptsList" classname="java.util.List"/> -->
<c:forEach var="script" items="${list }">
<script text="text/javascript" src="${script }"></script>
</c:forEach>
From the structure above, I am getting an ServletException on the default.jspx file which might be caused by the <tiles:useAttribute>
UPDATE:
The answer of #java1337 not worked but file management can be an issue as stated above.
Updated the question for clarifications.

Browser can't access/find relative resources like CSS, images and links when calling a Servlet which forwards to a JSP

I'm having trouble with loading CSS and images and creating links to other pages when I have a servlet forward to a JSP. Specifically, when I set my <welcome-file> to index.jsp, the CSS is being loaded and my images are being displayed. However, if I set my <welcome-file> to HomeServlet which forwards control to index.jsp, the CSS is not being applied and my images are not being displayed.
My CSS file is in web/styles/default.css.
My images are in web/images/.
I'm linking to my CSS like so:
<link href="styles/default.css" rel="stylesheet" type="text/css" />
I'm displaying my images as follows:
<img src="images/image1.png" alt="Image1" />
How is this problem caused and how can I solve it?
Update 1: I've added the structure of the application, as well as some other information that might help.
The header.jsp file is the file that contains the link tag for the CSS. The HomeServlet is set as my welcome-file in web.xml:
<welcome-file-list>
<welcome-file>HomeServlet</welcome-file>
</welcome-file-list>
The servlet is declared and mapped as followes in the web.xml:
<servlet>
<servlet-name>HomeServlet</servlet-name>
<servlet-class>com.brianblog.frontend.HomeServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>HomeServlet</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
Update 2: I found the problem finally - my servlet was mapped incorrectly. Apparently when setting a Servlet as your <welcome-file> it can't have a URL pattern of /, which I find sort of weird, because wouldn't that stand for the root directory of the site?
The new mapping is as follows:
<servlet-mapping>
<servlet-name>HomeServlet</servlet-name>
<url-pattern>/HomeServlet</url-pattern>
</servlet-mapping>
All relative URLs in the HTML page generated by the JSP file are relative to the current request URL (the URL as you see in the browser address bar) and not to the location of the JSP file in the server side as you seem to expect. It's namely the webbrowser who has to download those resources individually by URL, not the webserver who has to include them from disk somehow.
Apart from changing the relative URLs to make them relative to the URL of the servlet instead of the location of the JSP file, another way to fix this problem is to make them relative to the domain root (i.e. start with a /). This way you don't need to worry about changing the relative paths once again when you change the URL of the servlet.
<head>
<link rel="stylesheet" href="/context/css/default.css" />
<script src="/context/js/default.js"></script>
</head>
<body>
<img src="/context/img/logo.png" />
link
<form action="/context/servlet"><input type="submit" /></form>
</body>
However, you would probably like not to hardcode the context path. Very reasonable. You can obtain the context path in EL by ${pageContext.request.contextPath}.
<head>
<link rel="stylesheet" href="${pageContext.request.contextPath}/css/default.css" />
<script src="${pageContext.request.contextPath}/js/default.js"></script>
</head>
<body>
<img src="${pageContext.request.contextPath}/img/logo.png" />
link
<form action="${pageContext.request.contextPath}/servlet"><input type="submit" /></form>
</body>
(which can easily be shortened by <c:set var="root" value="${pageContext.request.contextPath}" /> and used as ${root} elsewhere)
Or, if you don't fear unreadable XML and broken XML syntax highlighting, use JSTL <c:url>:
<head>
<link rel="stylesheet" href="<c:url value="/css/default.css" />" />
<script src="<c:url value="/js/default.js" />"></script>
</head>
<body>
<img src="<c:url value="/img/logo.png" />" />
link
<form action="<c:url value="/servlet" />"><input type="submit" /></form>
</body>
Either way, this is in turn pretty cumbersome if you have a lot of relative URLs. For that you can use the <base> tag. All relative URL's will instantly become relative to it. It has however to start with the scheme (http://, https://, etc). There's no neat way to obtain the base context path in plain EL, so we need a little help of JSTL here.
<%#taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%#taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %>
<c:set var="req" value="${pageContext.request}" />
<c:set var="uri" value="${req.requestURI}" />
<c:set var="url">${req.requestURL}</c:set>
...
<head>
<base href="${fn:substring(url, 0, fn:length(url) - fn:length(uri))}${req.contextPath}/" />
<link rel="stylesheet" href="css/default.css" />
<script src="js/default.js"></script>
</head>
<body>
<img src="img/logo.png" />
link
<form action="servlet"><input type="submit" /></form>
</body>
This has in turn (again) some caveats. Anchors (the #identifier URL's) will become relative to the base path as well! You would like to make it relative to the request URL (URI) instead. So, change like
jump
to
jump
Each way has its own pros and cons. It's up to you which to choose. At least, you should now understand how this problem is caused and how to solve it :)
See also:
Is it recommended to use the <base> html tag?
I faced similar issue with Spring MVC application. I used < mvc:resources > tag to resolve this issue.
Please find the following link having more details.
http://www.mkyong.com/spring-mvc/spring-mvc-how-to-include-js-or-css-files-in-a-jsp-page/
You must analyse the actual HTML output, for the hint.
By giving the path like this means "from current location", on the other hand if you start with a / that would mean "from the context".
Your welcome page is set as That Servlet . So all css , images path should be given relative to that servlet DIR . which is a bad idea ! why do you need the servlet as a home page ? set .jsp as index page and redirect to any page from there ?
are you trying to populate any fields from db is that why you are using servlet ?
If you are using Spring MVC, then you need to declare default action servlet for static contents. Add the following entries in spring-action-servlet.xml. It worked for me.
NOTE: keep all the static contents outside WEB-INF.
<!-- Enable annotation-based controllers using #Controller annotations -->
<bean id="annotationUrlMapping" class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping">
<property name="order" value="0" />
</bean>
<bean id="controllerClassNameHandlerMapping" class="org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping">
<property name="order" value="1" />
</bean>
<bean id="annotationMethodHandlerAdapter" class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"/>
As for your update, I was confused for the reasoning behind in. Dug a little deeper and found this gem:
yoursite.com becomes yoursite.com/
yoursite.com/ is a directory, so the welcome-file-list is scanned
yoursite.com/CMS is the first welcome-file ("CMS" in the welcome-file-list), and there is a mapping of /CMS to the MyCMS servlet, so that servlet is accessed.
Source: http://wiki.metawerx.net/wiki/HowToUseAServletAsYourMainWebPage
So, the mapping then does make sense.
And one can now freely use ${pageContext.request.contextPath}/path/ as src/href for relative links!
short answer - add following line in the jsp which will define the base
base href="/{root of your application}/"
Below code worked for me.
instead of
use
<%# include file="styles/default.css"%>
You can try out this one as well as. Because this worked for me and it's simple.
<style>
<%# include file="/css/style.css" %>
</style>

Resources