Get Root/Base Url In Spring MVC

What is the best way to get the root/base url of a web application in Spring MVC?

Base Url = http://www.example.com or http://www.example.com/VirtualDirectory

If base url is "http://www.example.com", then use the following to get the "www.example.com" part, without the "http://":

From a Controller:

@RequestMapping(value = "/someURL", method = RequestMethod.GET)
public ModelAndView doSomething(HttpServletRequest request) throws IOException{
    //Try this:
    request.getLocalName(); 
    // or this
    request.getLocalAddr();
}

From JSP:

Declare this on top of your document:

<c:set var="baseURL" value="${pageContext.request.localName}"/> //or ".localAddr"

Then, to use it, reference the variable:

<a href="http://${baseURL}">Go Home</a>

You can also create your own method to get it:

public String getURLBase(HttpServletRequest request) throws MalformedURLException {

    URL requestURL = new URL(request.getRequestURL().toString());
    String port = requestURL.getPort() == -1 ? "" : ":" + requestURL.getPort();
    return requestURL.getProtocol() + "://" + requestURL.getHost() + port;

}

request.getRequestURL().toString().replace(request.getRequestURI(), request.getContextPath())

Wins

In controller, use HttpServletRequest.getContextPath().

In JSP use Spring's tag library: or jstl

I prefer to use

final String baseUrl = ServletUriComponentsBuilder.fromCurrentContextPath().build().toUriString();

It returns a completely built URL, scheme, server name and server port, rather than concatenating and replacing strings which is error prone.

Either inject a UriCompoenentsBuilder:

@RequestMapping(yaddie yadda)
public void doit(UriComponentBuilder b) {
  //b is pre-populated with context URI here
}

. Or make it yourself (similar to Salims answer):

// Get full URL (http://user:pwd@www.example.com/root/some?k=v#hey)
URI requestUri = new URI(req.getRequestURL().toString());
// and strip last parts (http://user:pwd@www.example.com/root)
URI contextUri = new URI(requestUri.getScheme(), 
                         requestUri.getAuthority(), 
                         req.getContextPath(), 
                         null, 
                         null);

You can then use UriComponentsBuilder from that URI:

// http://user:pwd@www.example.com/root/some/other/14
URI complete = UriComponentsBuilder.fromUri(contextUri)
                                   .path("/some/other/{id}")
                                   .buildAndExpand(14)
                                   .toUri();

Simply :

String getBaseUrl(HttpServletRequest req) {
    return req.getScheme() + "://" + req.getServerName() + ":" + req.getServerPort() + req.getContextPath();
}

danny.lesnik

     @RequestMapping(value="/myMapping",method = RequestMethod.POST)
      public ModelandView myAction(HttpServletRequest request){

       //then follow this answer to get your Root url
     }

Root URl of the servlet

If you need it in jsp then get in in controller and add it as object in ModelAndView.

Alternatively, if you need it in client side use javascript to retrieve it: http://www.gotknowhow.com/articles/how-to-get-the-base-url-with-javascript

jakobklamra

I think the answer to this question: Finding your application's URL with only a ServletContext shows why you should use relative url's instead, unless you have a very specific reason for wanting the root url.

In JSP

<c:set var="scheme" value="${pageContext.request.scheme}"/>
<c:set var="serverPort" value="${pageContext.request.serverPort}"/>
<c:set var="port" value=":${serverPort}"/>

<a href="${scheme}://${pageContext.request.serverName}${port}">base url</a>

reference https://github.com/spring-projects/greenhouse/blob/master/src/main/webapp/WEB-INF/tags/urls/absoluteUrl.tag

来源：https://stackoverflow.com/questions/5012525/get-root-base-url-in-spring-mvc

标签

spring-mvc

base-url