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();
}

如果你使用了.getRequestURL()中的StringBuffer的构建器模式，你可以用三元写一个简单的一行代码:

private String getUrlWithQueryParms(final HttpServletRequest request) { 
    return request.getQueryString() == null ? request.getRequestURL().toString() :
        request.getRequestURL().append("?").append(request.getQueryString()).toString();
}

但这只是语法糖。

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();
    }
}

我有一个用例来生成cURL命令(我可以在终端使用)从httpServletRequest实例。我创建了一个这样的方法。您可以直接在终端中复制粘贴此方法的输出

private StringBuilder generateCURL(final HttpServletRequest httpServletRequest) {
    final StringBuilder curlCommand = new StringBuilder();
    curlCommand.append("curl ");

    // iterating over headers.
    for (Enumeration<?> e = httpServletRequest.getHeaderNames(); e.hasMoreElements();) {
        String headerName = (String) e.nextElement();
        String headerValue = httpServletRequest.getHeader(headerName);
        // skipping cookies, as we're appending cookies separately.
        if (Objects.equals(headerName, "cookie")) {
            continue;
        }
        if (headerName != null && headerValue != null) {
            curlCommand.append(String.format(" -H \"%s:%s\" ", headerName, headerValue));
        }
    }

    // iterating over cookies.
    final Cookie[] cookieArray = httpServletRequest.getCookies();
    final StringBuilder cookies = new StringBuilder();
    for (Cookie cookie : cookieArray) {
        if (cookie.getName() != null && cookie.getValue() != null) {
            cookies.append(cookie.getName());
            cookies.append('=');
            cookies.append(cookie.getValue());
            cookies.append("; ");
        }
    }
    curlCommand.append(" --cookie \"" + cookies.toString() + "\"");

    // appending request url.
    curlCommand.append(" \"" + httpServletRequest.getRequestURL().toString() + "\"");
    return curlCommand;
}

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。

结合getRequestURL()和getQueryString()的结果应该会得到您想要的结果。