Accessing the full url, including hostname with jstl

Question

<c:url var="myUrl" value="/MyPath/${MyID}"/>

which I then use later (to enable users to copy links) :

<input size="35" disabled value="${myUrl}" />

and it shows

/my-app-name/MyPath/23

however I want it to be

http://myHost/my-app-name/MyPath/23

I can prepend the string sure, but wanted a way to actively get the correct hostname ... ?

Solution 1

You need to prepare it yourself based on HttpServletRequest#getRequestURL() and a little help of JSTL functions:

<c:set var="req" value="${pageContext.request}" />
<c:set var="baseURL" value="${fn:replace(req.requestURL, fn:substring(req.requestURI, 1, fn:length(req.requestURI)), req.contextPath)}" />
...
<c:url var="myUrl" value="${baseURL}/${MyID}"/>

Solution 2

HttpServletRequest object has all the details:

• getProtocol
• getServerName
• getContextPath

so I think you can use:

${request.protocol} :// ${request.serverName} ${request.contextPath} /etc

to build what you want.

Comments

[NimChimpsky]

that was quick, thnx, will give it a shot.

[BalusC]

You would only end up in a clumsy if-else logic flow in order to hide the port whenever it's already the default port for the given protocol. It's easier to build based on getRequestURL(). Also, the getServerName() is manipulatable by the client through the Host request header, I wouldn't rely on this.

[helios]

Ok. I didn't think about hiding the port. I didn't go the getRequestURL way because the OP wanted to change the URL. One question. I didn't understood the servername manipulation. Is it that if the client send a Host:www.other.com that will get into our built URL?

[cthiebaud]

on tomcat 7.0.52, I had to change the start of the substring from 1 to 0 : fn:substring(req.requestURI, 0, fn:length(req.requestURI)), etc.

[cthiebaud]

even better, on tomcat 7.0.52, simplified baseURL works for me: <c:set var="baseURL" value="${fn:replace(req.requestURL, req.requestURI, req.contextPath)}" />

[BalusC]

@cthiebaud: this fails if webapp is deployed to context root and the request URI is "/". This also fails if the request URL contains -by coincidence- repeated parts of request URI. You'd really better substring off the exact part by index.

[Julien D]

got it working with ${pageContext.request.serverName}

[Francisco Souza]

What if I whant to get only the "page name", example: if i have localhost:8080/ticket/pages/cadastro.jsf then I need to check is "this" page is equal to "cadastro.jsf" (JSF/Primefaces) ?