mybaties连接sqlite，并读取blob类型数据时，报错 java.sql.SQLFeatureNotSupportedException

java.sql.SQLException: not implemented by SQLite JDBC driver

错误,或者如下错误：

2021-06-03 09:25:20.435 ERROR 15643 --- [nio-8080-exec-7] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: org.apache.ibatis.executor.result.ResultMapException: Error attempting to get column 'appIcon' from result set.  Cause: java.sql.SQLFeatureNotSupportedException
### The error may exist in xxxx.java (best guess)
### The error may involve xxx.select
### The error occurred while handling results
### SQL: SELECT * FROM xxx WHERE id=?
### Cause: org.apache.ibatis.executor.result.ResultMapException: Error attempting to get column 'appIcon' from result set.  Cause: java.sql.SQLFeatureNotSupportedException] with root cause

场景：
具体需求，要求像springboot连接mysql或者pgsql数据库一样，在application配置文件中配置sqlite数据库信息，并实现对blob类型数据（我们的库中有该类型的数据）的读写，按照平常一样写好controller、service、dao、mapper.xml后，执行查询操作后报错

原因分析：
sqlite的driver中，JDBC4ResultSet没有实现以下接口：

public Blob getBlob(int col)
throws SQLException { throw unused(); }
public Blob getBlob(String col)
throws SQLException { throw unused(); }

而是直接抛出了异常。
解决方法：
mapper.xml中该字段的设置：

<select id="queryByList" resultMap="queryBaseResultMap">
    select * from my_blob 
</select>
<resultMap id="queryBaseResultMap" type="com.wx.model.MyBlob" >
    <id column="Id" property="id" jdbcType="INTEGER" />
    <result column="blob" property="blob" typeHandler="com.wx.handler.BlobTypeHandler"/> 
</resultMap>

即blob字段加个typeHandler属性。
然后自定义一个BlobTypeHandler处理类：

public class BlobTypeHandler extends BaseTypeHandler<byte[]> {

    @Override
    public void setNonNullParameter(PreparedStatement ps, int i, byte[] parameter, JdbcType jdbcType) throws SQLException {
        ps.setBytes(i, parameter);
    }

    @Override
    public byte[] getNullableResult(ResultSet rs, String columnName) throws SQLException {
        return rs.getBytes(columnName);
    }

    @Override
    public byte[] getNullableResult(ResultSet rs, int columnIndex) throws SQLException {
        return rs.getBytes(columnIndex);
    }

    @Override
    public byte[] getNullableResult(CallableStatement cs, int columnIndex) throws SQLException {
        return cs.getBytes(columnIndex);
    }
}

注意：实体类中blob字段类型是byte[]。

参考链接

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mybaties连接sqlite，并读取blob类型数据时，报 java.sql.SQLException: not implemented by SQLite JDBC driver错误