Enumeration<String> e = request.getParameterNames();
FormParameters params = new FormParameters(request);
while (e.hasMoreElements()) {
String key = e.nextElement();
FormParameter param = parseParameterKey(key);
// param为null表示该参数不是从form service生成的,忽略之
if (param != null) {
if (!logStarted) {
logStarted = true;