wro4j-core/src/main/java/ro/isdc/wro/http/support/ContentTypeResolver.java
public static String get(final String fileName, final String encoding) {
    final String contentType = get(fileName);
    if (requiresCharset.contains(contentType)) {
      return contentType + "; charset=" + encoding;
    }
    return contentType;
  }
public static String get(final String fileName, final String encoding) {
    final String contentType = get(fileName);
    if (requiresCharset.contains(contentType)) {
      return contentType + "; charset=" + encoding;
    }
    return contentType;
  }
Returns a valid HTTP contentType's for a given filename with charset. It first relies on the custom
defaultContentTypeMap and if not found it will fall back to defaultFileTypeMap from javax.activation.FileTypeMap.
Examples: - ("somefile.css", "UTF-8") resolves to "text/css"; charset=UTF-8". - ("somefile.js.png", "UTF-8")
resolves to "image/png" - ("/blah/index.html, "UTF-8") resolves to "text/html; charset=8"

@param fileName
with an filename extension
@param encoding
which encoding to use
@return contentType