load和get

参考：hibernate延迟加载(get和load的区别)

Hibernate之load和get的区别

get方法的doc解释：

    /**
     * Return the persistent instance of the given entity class with the given identifier,
     * or null if there is no such persistent instance. (If the instance is already associated
     * with the session, return that instance. This method never returns an uninitialized instance.)
     *
     * @param entityType The entity type
     * @param id an identifier
     *
     * @return a persistent instance or null
     */
    <T> T get(Class<T> entityType, Serializable id);

load方法的doc解释：

    /**
     * Return the persistent instance of the given entity class with the given identifier,
     * assuming that the instance exists. This method might return a proxied instance that
     * is initialized on-demand, when a non-identifier method is accessed.
     * You should not use this method to determine if an instance exists (use get()
     * instead). Use this only to retrieve an instance that you assume exists, where non-existence
     * would be an actual error.
     *
     * @param theClass a persistent class
     * @param id a valid identifier of an existing persistent instance of the class
     *
     * @return the persistent instance or proxy
     */
    <T> T load(Class<T> theClass, Serializable id);