import com.sun.org.apache.xml.internal.utils.URI.MalformedURIException; //导入依赖的package包/类
/**
 * Take a SystemID string and try to turn it into a good absolute URI.
 *
 * @param urlString SystemID string
 * @param base The URI string used as the base for resolving the systemID
 *
 * @return The resolved absolute URI
 * @throws TransformerException thrown if the string can't be turned into a URI.
 */
public static String getAbsoluteURI(String urlString, String base)
        throws TransformerException
{
  if (base == null)
    return getAbsoluteURI(urlString);

  String absoluteBase = getAbsoluteURI(base);
  URI uri = null;
  try
  {
    URI baseURI = new URI(absoluteBase);
    uri = new URI(baseURI, urlString);
  }
  catch (MalformedURIException mue)
  {
    throw new TransformerException(mue);
  }

  return replaceChars(uri.toString());
}