我尝试实现一个Guice模块,让Guacamole使用SQLite作为后端。 Guacamole项目有一个通用的JDBC基础模块。这使您可以使用更少的代码实现特定数据存储的模块。大多数代码行最终都在映射器XML文件中。该项目提供了PostgreSQL and MySQL implementations。
我将这个SQLite模块基于MySQL模块。对于映射器XML文件,SQLite和MySQL足够相似,我没有做任何更改。但是,当我尝试使用SQLite模块时,我收到此错误:
### Error querying database. Cause: java.lang.ArrayIndexOutOfBoundsException: 2
### The error may exist in org/apache/guacamole/auth/jdbc/connectiongroup/ConnectionGroupMapper.xml
### The error may involve defaultParameterMap
### The error occurred while setting parameters
### SQL: SELECT guacamole_connection_group.connection_group_id, connection_group_name, parent_id, type, max_connections, max_connections_per_user, enable_session_affinity FROM guacamole_connection_group JOIN guacamole_connection_group_permission ON guacamole_connection_group_permission.connection_group_id = guacamole_connection_group.connection_group_id WHERE guacamole_connection_group.connection_group_id IN ( ? ) AND user_id = ? AND permission = 'READ'; SELECT parent_id, guacamole_connection_group.connection_group_id FROM guacamole_connection_group JOIN guacamole_connection_group_permission ON guacamole_connection_group_permission.connection_group_id = guacamole_connection_group.connection_group_id WHERE parent_id IN ( ? ) AND user_id = ? AND permission = 'READ'; SELECT parent_id, guacamole_connection.connection_id FROM guacamole_connection JOIN guacamole_connection_permission ON guacamole_connection_permission.connection_id = guacamole_connection.connection_id WHERE parent_id IN ( ? ) AND user_id = ? AND permission = 'READ';
### Cause: java.lang.ArrayIndexOutOfBoundsException: 2
看起来问题是两个参数传递给查询,但每个参数重复三次。当MyBatis生成PreparedStatement时,它就好像有六个参数需要传入。
以下是有问题的查询:
<!-- Select multiple connection groups by identifier only if readable -->
<select id="selectReadable" resultMap="ConnectionGroupResultMap"
resultSets="connectionGroups,childConnectionGroups,childConnections">
SELECT
guacamole_connection_group.connection_group_id,
connection_group_name,
parent_id,
type,
max_connections,
max_connections_per_user,
enable_session_affinity
FROM guacamole_connection_group
JOIN guacamole_connection_group_permission ON guacamole_connection_group_permission.connection_group_id = guacamole_connection_group.connection_group_id
WHERE guacamole_connection_group.connection_group_id IN
<foreach collection="identifiers" item="identifier"
open="(" separator="," close=")">
#{identifier,jdbcType=VARCHAR}
</foreach>
AND user_id = #{user.objectID,jdbcType=INTEGER}
AND permission = 'READ';
SELECT parent_id, guacamole_connection_group.connection_group_id
FROM guacamole_connection_group
JOIN guacamole_connection_group_permission ON guacamole_connection_group_permission.connection_group_id = guacamole_connection_group.connection_group_id
WHERE parent_id IN
<foreach collection="identifiers" item="identifier"
open="(" separator="," close=")">
#{identifier,jdbcType=VARCHAR}
</foreach>
AND user_id = #{user.objectID,jdbcType=INTEGER}
AND permission = 'READ';
SELECT parent_id, guacamole_connection.connection_id
FROM guacamole_connection
JOIN guacamole_connection_permission ON guacamole_connection_permission.connection_id = guacamole_connection.connection_id
WHERE parent_id IN
<foreach collection="identifiers" item="identifier"
open="(" separator="," close=")">
#{identifier,jdbcType=VARCHAR}
</foreach>
AND user_id = #{user.objectID,jdbcType=INTEGER}
AND permission = 'READ';
</select>
如果我手动填充参数,我可以对SQLite数据库执行此操作。此外,MySQL版本工作正常。
到底发生了什么事?我该怎么做才能调试这个?它是MyBatis问题还是JDBC连接器的问题?
如果有帮助,您可以看到模块here的代码。
这是映射器与此查询相关的参数的方法。 ConnectionGroup的完整映射器类是here和here。我的SQLite模块的完整映射器XML是here。
Collection<ModelType> selectReadable(@Param("user") UserModel user,
@Param("identifiers") Collection<String> identifiers);
这就是ConnectionGroupResultMap
的样子:
<resultMap id="ConnectionGroupResultMap" type="org.apache.guacamole.auth.jdbc.connectiongroup.ConnectionGroupModel" >
<!-- Connection group properties -->
<id column="connection_group_id" property="objectID" jdbcType="INTEGER"/>
<result column="connection_group_name" property="name" jdbcType="VARCHAR"/>
<result column="parent_id" property="parentIdentifier" jdbcType="INTEGER"/>
<result column="type" property="type" jdbcType="VARCHAR"
javaType="org.apache.guacamole.net.auth.ConnectionGroup$Type"/>
<result column="max_connections" property="maxConnections" jdbcType="INTEGER"/>
<result column="max_connections_per_user" property="maxConnectionsPerUser" jdbcType="INTEGER"/>
<result column="enable_session_affinity" property="sessionAffinityEnabled" jdbcType="BOOLEAN"/>
<!-- Child connection groups -->
<collection property="connectionGroupIdentifiers" resultSet="childConnectionGroups" ofType="java.lang.String"
column="connection_group_id" foreignColumn="parent_id">
<result column="connection_group_id"/>
</collection>
<!-- Child connections -->
<collection property="connectionIdentifiers" resultSet="childConnections" ofType="java.lang.String"
column="connection_group_id" foreignColumn="parent_id">
<result column="connection_id"/>
</collection>
</resultMap>
答案 0 :(得分:1)
大卫,
我知道这有点旧,但我也试图实现一个SQLite JDBC模块,并遇到了完全相同的问题。我设法找到了问题的根源,并在JDBC SQLite github页面上提出了一个问题:
https://github.com/xerial/sqlite-jdbc/issues/277
基本上,SQLite JDBC驱动程序根据预准备语句的参数计数来计算其数组大小之一。但是,在您提到的情况下,有多个SELECT语句采用相同的参数,因此数组需要是x * y(x =参数计数,y = select语句的数量),而不仅仅是参数的数量。当它尝试准备语句时,它会超出参数计数的第一个位置并生成此异常。
其他JDBC模块--MySQL,PostgreSQL和SQL Server,以及我正在搞砸的Oracle和H2 - 似乎正确处理了这种情况(好吧,Oracle有点......特别.. 。),但SQLite驱动程序没有。
通过创建两个不同的结果映射,一个用于泛型选择,一个用于检查READ权限的读取,然后分解每个选择,我能够以真正,非常复杂的方式解决该问题。查询自己的SELECT块并从结果映射中的集合中调用它们。它没有现有代码那么优雅,但它确实有效。