java - Spring Boot H2数据转换

Question

Spring Boot版本:2.1.2.RELEASE
H2版本:1.4.197
通过 JpaRepository 查询:

@Repository
public interface PlayerStorage extends JpaRepository<Player, Long> {
  List<Player> findByUid(@Param("uid") List<Integer> uid);
}
...
List<Player> foundByUids = playerStorage.findByUid(Arrays.asList(100, 200));

Spring 生成并执行查询:

Data conversion error converting "(100, 200)"; SQL statement:
select
        player0_.id as id1_3_,
        player0_.uid as uid3_3_ 
    from
        player player0_ 
    where
        player0_.uid=(100 , 200)
[22018-197]
...
Caused by: java.lang.NumberFormatException: For input string: "(100, 200)"
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
at java.lang.Integer.parseInt(Integer.java:569)
at java.lang.Integer.parseInt(Integer.java:615)
at org.h2.value.Value.convertTo(Value.java:1061)

H2 说:

DATA_CONVERSION_ERROR_1 = 22018
The error with code 22018 is thrown when trying to convert a value to a data type where the conversion is undefined, or when an error occurred trying to convert.
Example:
CALL CAST(DATE '2001-01-01' AS BOOLEAN);
CALL CAST('CHF 99.95' AS INT);

如果我尝试直接从 H2 Web 控制台执行此查询，我会得到相同的结果。如果我没猜错的话，问题出在语句中:player0_.uid=(100 , 200)。与 in player0_.uid in (100 , 200) 相同的查询可以从 Web 控制台正常执行。

我还有 H2 的 spring boot 属性:

spring.datasource.driver-class-name=org.h2.Driver
spring.jpa.database=H2
spring.jpa.database-platform=org.hibernate.dialect.H2Dialect

Answer 1

错误可能出在存储库代码中:

public interface PlayerStorage extends JpaRepository<Player, Long> {
  List<Player> findByUid(@Param("uid") List<Integer> uid);
}

来自documentation应该是:

public interface PlayerStorage extends JpaRepository<Player, Long> {
  List<Player> findByUidIn(@Param("uid") List<Integer> uid);
}

另外:

• 如果Player中的字段为“uid”，则不需要@Param
• @Repository 也是多余的
• 我建议添加一些验证，确保传递给该方法的列表不为空，否则会导致异常。