JDBI与Kotlin映射异常：根据用户名查询用户失败

开发者阿泽

2026-8-20

解决JDBI映射Kotlin User数据类时的构造参数匹配异常

异常信息

Exception in thread "main" java.lang.IllegalArgumentException: Mapping Kotlin type User didn't find any columns matching required, non-default constructor parameters in result set
at org.jdbi.v3.core.kotlin.KotlinMapper.specialize$lambda-3(KotlinMapper.kt:72)
at java.base/java.util.Optional.orElseThrow(Optional.java:403)
at org.jdbi.v3.core.kotlin.KotlinMapper.specialize(KotlinMapper.kt:71)
at org.jdbi.v3.core.result.ResultSetResultIterator.<init>(ResultSetResultIterator.java:38)
at org.jdbi.v3.core.result.ResultIterable.lambda$of$0(ResultIterable.java:57)
at org.jdbi.v3.core.result.ResultIterable.one(ResultIterable.java:145)
at JdbiUserRepository.getById$lambda-1(Main.kt:75)
at org.jdbi.v3.core.Jdbi.withHandle(Jdbi.java:357)
at JdbiUserRepository.getById(Main.kt:70)
at MainKt.main(Main.kt:22)
at MainKt.main(Main.kt)

核心问题

查询SQL语句select from users where username = :username未指定要查询的列，执行后返回的结果集不包含任何列数据。而Kotlin数据类User的构造函数需要username和password两个必填参数，JDBI无法找到对应的列值来构造对象，因此抛出映射异常。

解决方案

修改查询语句，明确指定要查询的username和password列，确保结果集包含构造User所需的全部字段：

修改后的查询方法

class JdbiUserRepository(private val jdbi: Jdbi) : UserRepository {

    override fun getById(username: String): User? = jdbi
        .withHandle<User?, Exception> { handle -> handle
            .createQuery("select username, password from users where username = :username")
            .bind("username", username)
            .mapTo<User>()
            .one()
        }
}