SiteUrl.java

package sagan.blog.support;

import javax.servlet.http.HttpServletRequest;

import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

@Component
class SiteUrl {

    public String getUrl() {
        HttpServletRequest request =
                ((ServletRequestAttributes) RequestContextHolder.currentRequestAttributes()).getRequest();
        String requestURL = request.getRequestURL().toString();
        String requestURI = request.getRequestURI();
        return requestURL.replace(requestURI, "");
    }

    public String getAbsoluteUrl(String path) {
        return getUrl() + path;
    }
}