无法确定我的标题是否足够清晰。 这里指的是 : I m 正在开发一个网络应用程序, 使用 < code> spring 3. 0.5 + hibernate 3.6. 1. RELESE , 使用 < code> JPA 注释 , 使用 < code > sessionFactory 。 应用程序允许用户使用 < code > username , < code > email 和 < code> password 注册。
用户可以使用 (用户名或电子邮件) 和 password 和 password 登录。
java.sql.BatchUptidateExption: USERNAME 关键词或org.hibertate. 例外。 限制 Vislation Exception: 无法执行 JDBC 批次更新的重复条目用户名 或org.hibertate. exception: 无法执行 JDBC 批次更新
如果我能得到一个特定的例外,我可以通知用户他的用户名或电子邮件已被使用。
还有什么其他解决方案? 最佳做法是什么?
谢谢你看这个
实际上,最佳做法是,在创建新用户时,检查使用该用户名/电子邮件地址的用户是否已经存在。如果存在,则返回某东西以显示失败,否则创建用户。
通常您不应依赖数据库限制来执行商业规则。
我想做选择检查是没问题的
一般来说,如果您正在创建独特的身份识别码,这些身份识别码应该是独特的,因此,违反独特的身份识别码是一种例外的错误情况,应当通过抓住例外处理。
但在这里, 您再次让用户提供希望中唯一的密钥 。 您不能认为这些密钥真的不是唯一的。 所以, 您应该先检查用户名是否被取出, 然后再尝试创建用户对象 。
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