code: public StringBuffer rewriteUrl(String originalCssPath, String newCssPath, String originalCssContent)
  			throws IOException {
  
  		// Rewrite each css image url path
  		Matcher matcher = URL_PATTERN.matcher(originalCssContent);
  		StringBuffer sb = new StringBuffer();
  		while (matcher.find()) {
  
  			String url = getUrlPath(matcher.group(), originalCssPath, newCssPath);
  			matcher.appendReplacement(sb, RegexUtil.adaptReplacementToMatcher(url));
  		}
  		matcher.appendTail(sb);
  		return sb;
  	}
docs: Rewrites the image URL
  
  @param originalCssPath
  the original CSS path
  @param newCssPath
  the new CSS path
  @param originalCssContent
  the original CSS content
  @return the new CSS content with image path rewritten
  @throws IOException
  if an IO exception occurs