private Class<T> clz;
@SuppressWarnings("unchecked")
public Class<T> getClz() {
if (clz == null) {
// 获取泛型的Class对象
clz = ((Class<T>) (((ParameterizedType) (this.getClass()
.getGenericSuperclass())).getActualTypeArguments()[0]));
}
return clz;
}