我有一个HttpServletRequest对象。

我如何获得导致这个调用到达我的servlet的完整而准确的URL ?

或者至少尽可能准确,因为有些东西是可以重新生成的(也许是参数的顺序)。


当前回答

当请求被转发时,例如从反向代理,HttpServletRequest.getRequestURL()方法将不会返回被转发的url,而是返回本地url。 当设置了x-forwarded-* Headers时,这可以很容易地处理:

public static String getCurrentUrl(HttpServletRequest request) {
    String forwardedHost = request.getHeader("x-forwarded-host");

    if(forwardedHost == null) {
        return request.getRequestURL().toString();
    }

    String scheme = request.getHeader("x-forwarded-proto");
    String prefix = request.getHeader("x-forwarded-prefix");

    return scheme + "://" + forwardedHost + prefix + request.getRequestURI();
}

这缺少查询部分,但可以在其他答案中添加。我来这里,是因为我特别需要转发的东西,希望能帮助别人解决这个问题。

其他回答

// http://hostname.com/mywebapp/servlet/MyServlet/a/b;c=123?d=789

public static String getUrl(HttpServletRequest req) {
    String reqUrl = req.getRequestURL().toString();
    String queryString = req.getQueryString();   // d=789
    if (queryString != null) {
        reqUrl += "?"+queryString;
    }
    return reqUrl;
}

HttpServletRequest有以下方法:

getRequestURL() -在查询字符串分隔符之前返回完整URL的部分? getQueryString() -在查询字符串分隔符后返回完整URL的部分?

所以,要获得完整的URL,只需做:

public static String getFullURL(HttpServletRequest request) {
    StringBuilder requestURL = new StringBuilder(request.getRequestURL().toString());
    String queryString = request.getQueryString();

    if (queryString == null) {
        return requestURL.toString();
    } else {
        return requestURL.append('?').append(queryString).toString();
    }
}

有点晚了,但我把它包括在我的MarkUtils-Web库中的WebUtils - Checkstyle-approved和junit - tests:

import javax.servlet.http.HttpServletRequest;

public class GetRequestUrl{
    /**
     * <p>A faster replacement for {@link HttpServletRequest#getRequestURL()}
     *  (returns a {@link String} instead of a {@link StringBuffer} - and internally uses a {@link StringBuilder})
     *  that also includes the {@linkplain HttpServletRequest#getQueryString() query string}.</p>
     * <p><a href="https://gist.github.com/ziesemer/700376d8da8c60585438"
     *  >https://gist.github.com/ziesemer/700376d8da8c60585438</a></p>
     * @author Mark A. Ziesemer
     *  <a href="http://www.ziesemer.com.">&lt;www.ziesemer.com&gt;</a>
     */
    public String getRequestUrl(final HttpServletRequest req){
        final String scheme = req.getScheme();
        final int port = req.getServerPort();
        final StringBuilder url = new StringBuilder(256);
        url.append(scheme);
        url.append("://");
        url.append(req.getServerName());
        if(!(("http".equals(scheme) && (port == 0 || port == 80))
                || ("https".equals(scheme) && port == 443))){
            url.append(':');
            url.append(port);
        }
        url.append(req.getRequestURI());
        final String qs = req.getQueryString();
        if(qs != null){
            url.append('?');
            url.append(qs);
        }
        final String result = url.toString();
        return result;
    }
}

可能是目前为止最快和最强大的答案,仅次于Mat Banik的答案——但即使是他的答案也没有考虑到HTTP/HTTPS的潜在非标准端口配置。

参见:

http://blogger.ziesemer.com/2017/08/httpservletrequestgetrequesturl.html https://gist.github.com/ziesemer/700376d8da8c60585438

你可以使用滤镜。

@Override
public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2) throws IOException, ServletException {
        HttpServletRequest test1=    (HttpServletRequest) arg0;
       
     test1.getRequestURL()); it gives  http://localhost:8081/applicationName/menu/index.action
     test1.getRequestURI()); it gives applicationName/menu/index.action
     String pathname = test1.getServletPath()); it gives //menu/index.action
      
  
    if(pathname.equals("//menu/index.action")){ 
        arg2.doFilter(arg0, arg1); // call to urs servlet or frameowrk managed controller method


       // in resposne 
       HttpServletResponse httpResp = (HttpServletResponse) arg1;
       RequestDispatcher rd = arg0.getRequestDispatcher("another.jsp");     
       rd.forward(arg0, arg1);
}

不要忘记在web.xml的filter mapping中放入<dispatcher>FORWARD</dispatcher>

我使用这个方法:

public static String getURL(HttpServletRequest req) {

    String scheme = req.getScheme();             // http
    String serverName = req.getServerName();     // hostname.com
    int serverPort = req.getServerPort();        // 80
    String contextPath = req.getContextPath();   // /mywebapp
    String servletPath = req.getServletPath();   // /servlet/MyServlet
    String pathInfo = req.getPathInfo();         // /a/b;c=123
    String queryString = req.getQueryString();          // d=789

    // Reconstruct original requesting URL
    StringBuilder url = new StringBuilder();
    url.append(scheme).append("://").append(serverName);

    if (serverPort != 80 && serverPort != 443) {
        url.append(":").append(serverPort);
    }

    url.append(contextPath).append(servletPath);

    if (pathInfo != null) {
        url.append(pathInfo);
    }
    if (queryString != null) {
        url.append("?").append(queryString);
    }
    return url.toString();
}