if (cachedType != null) { // 缓存命中,直接返回
return cachedType;
}
Type parameterType = parameterTypeMap.get(parameterName);
if (parameterType == null ) {
throw new NotReadableParameterException("parameter ':" + parameterName + "' is not readable");
}
Type type = !propertyPath.isEmpty() ?
TypeUtil.getPropertyType(parameterType, parameterName, propertyPath) :
parameterType;
cache.put(key, type);