DBCPConnectionPool用于SQL Server的控制器服务，jdbc异常

Question

在Windows 7和RHEL 7上测试了NiFi 1.1.1。

后台主题是here。

我创建了一个指向SQL Server数据库的DBCPConnectionPool控制器服务，我能够从表中获取数据并将其写入本地磁盘（ExecuteSQL - ＆gt; ConvertAvroToJSON - ＆gt; PutFile）。

我的代码：

public byte[] getMaxLSN(Connection connection, String containerDB) {
    String dbMaxLSN = "{? = CALL sys.fn_cdc_get_max_lsn()}";
    byte[] maxLSN = null;

    try (final CallableStatement cstmt = connection.prepareCall(dbMaxLSN);) {

        cstmt.registerOutParameter(1, java.sql.JDBCType.BINARY);
        cstmt.execute();

        if (cstmt.getBytes(1) == null || cstmt.getBytes(1).length <= 0) {

            System.out.println("Coudln't retrieve the max lsn for the db "
                    + containerDB);

        } else {
            maxLSN = cstmt.getBytes(1);

        }
    } catch (SQLException sqlException) {
        System.out.println("sqlException !!!");
        sqlException.printStackTrace();
    }

    return maxLSN;
}

当我在自定义处理器中将池用作属性时，出现了挑战。在处理器的代码中，我需要在db中调用一个函数，但这会导致指向JDBC驱动程序的 SQLException。请注意，相同的驱动程序在独立的Java代码中正常运行（在后台线程中提供，以避免混乱此帖子）并从函数中获取返回值。我怀疑控制器服务配置不正确 - 它可以执行选择查询，但是当代码调用函数时，它会抛出异常。我错过了什么？

Process or SQL exception in <configure logger template to pick the code location>
2017-03-17 09:25:30,717 ERROR [Timer-Driven Process Thread-6] c.s.d.processors.SQLServerCDCProcessor 
org.apache.nifi.processor.exception.ProcessException: Coudln't retrieve the max lsn for the db test
    at com.datalake.processors.SQLServerCDCProcessor$SQLServerCDCUtils.getMaxLSN(SQLServerCDCProcessor.java:692) ~[nifi-NiFiCDCPoC-processors-1.0-SNAPSHOT.jar:1.0-SNAPSHOT]
    at com.datalake.processors.SQLServerCDCProcessor.getChangedTableQueries(SQLServerCDCProcessor.java:602) ~[nifi-NiFiCDCPoC-processors-1.0-SNAPSHOT.jar:1.0-SNAPSHOT]
    at com.datalake.processors.SQLServerCDCProcessor.onTrigger(SQLServerCDCProcessor.java:249) ~[nifi-NiFiCDCPoC-processors-1.0-SNAPSHOT.jar:1.0-SNAPSHOT]
    at org.apache.nifi.processor.AbstractProcessor.onTrigger(AbstractProcessor.java:27) [nifi-api-1.1.1.jar:1.1.1]
    at org.apache.nifi.controller.StandardProcessorNode.onTrigger(StandardProcessorNode.java:1099) [nifi-framework-core-1.1.1.jar:1.1.1]
    at org.apache.nifi.controller.tasks.ContinuallyRunProcessorTask.call(ContinuallyRunProcessorTask.java:136) [nifi-framework-core-1.1.1.jar:1.1.1]
    at org.apache.nifi.controller.tasks.ContinuallyRunProcessorTask.call(ContinuallyRunProcessorTask.java:47) [nifi-framework-core-1.1.1.jar:1.1.1]
    at org.apache.nifi.controller.scheduling.TimerDrivenSchedulingAgent$1.run(TimerDrivenSchedulingAgent.java:132) [nifi-framework-core-1.1.1.jar:1.1.1]
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [na:1.8.0_71]
    at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308) [na:1.8.0_71]
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180) [na:1.8.0_71]
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294) [na:1.8.0_71]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [na:1.8.0_71]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [na:1.8.0_71]
    at java.lang.Thread.run(Thread.java:745) [na:1.8.0_71]
Caused by: java.sql.SQLFeatureNotSupportedException: registerOutParameter not implemented
    at java.sql.CallableStatement.registerOutParameter(CallableStatement.java:2613) ~[na:1.8.0_71]
    at com.datalake.processors.SQLServerCDCProcessor$SQLServerCDCUtils.getMaxLSN(SQLServerCDCProcessor.java:677) ~[nifi-NiFiCDCPoC-processors-1.0-SNAPSHOT.jar:1.0-SNAPSHOT]
    ... 14 common frames omitted

Answer 1

“java.sql.SQLFeatureNotSupportedException：registerOutParameter not implemented”您的代码使用的是驱动程序中没有的功能。

具体来说，基于堆栈跟踪，您的驱动程序正在调用{4.2}（Java 8）中引入的registerOutParameter(int parameterIndex, SQLType sqlType)。此方法在java.sql.CallableStatement接口中具有以下默认实现：

default void registerOutParameter(int parameterIndex, SQLType sqlType)
    throws SQLException {
    throw new SQLFeatureNotSupportedException("registerOutParameter not implemented");
}

throw在java.sql.CallableStatement中与第2613行匹配，与堆栈跟踪匹配。

作为最新版本的Microsoft SQL Server JDBC驱动程序中的this method is implemented，您使用的是旧版本，或者驱动程序的对象包含在不支持JDBC 4.2的代理中。

我建议您升级到latest version of the driver，目前为v6.1.0。由于another question of yours建议您使用maven，因此您应该确保驱动程序的新 Maven坐标（他们在开源驱动程序时更改了它）：

<dependency>
    <groupId>com.microsoft.sqlserver</groupId>
    <artifactId>mssql-jdbc</artifactId>
    <version>6.1.0.jre8</version>
</dependency>

如果问题仍然存在，那么由于com.datalake.processors.SQLServerCDCProcessor是您自己的代码（如other question所示），您应该将其更改为不调用registerOutParameter(int parameterIndex, SQLType sqlType)，而是更早registerOutParameter(int parameterIndex, int sqlType) 1}}。