private String toCommaSeparatedString(List<?> proxyExceptions){
  StringBuilder result=new StringBuilder();
  for (  Object object : proxyExceptions) {
    if (result.length() > 0) {
      result.append(",");
    }
    result.append(object);
  }
  return result.toString();
}

private String toCommaSeparatedString ( List < ? > proxyExceptions ) { StringBuilder result = new StringBuilder ( ) ; for ( Object object : proxyExceptions ) { if ( result . length ( ) > 0 ) { result . append ( "," ) ; } result . append ( object ) ; } return result . toString ( ) ; }
convert a list to a comma separated list .
