java.lang.classcastException:com.datastax.driver.core.core.d

Question

我在试图在代码上运行时会遇到此错误。

错误：

  Exception:
    Caused by: java.lang.ClassCastException: com.datastax.driver.core.DefaultResultSetFuture cannot be cast to shade.com.datastax.spark.connector.google.common.util.concurrent.ListenableFuture
        at com.datastax.spark.connector.writer.AsyncExecutor.com$datastax$spark$connector$writer$AsyncExecutor$$tryFuture$1(AsyncExecutor.scala:38) ~[spark-cassandra-connector_2.11-2.3.1.jar:2.3.1]
        at com.datastax.spark.connector.writer.AsyncExecutor.executeAsync(AsyncExecutor.scala:71) ~[spark-cassandra-connector_2.11-2.3.1.jar:2.3.1]
        at com.datastax.spark.connector.writer.TableWriter$$anonfun$writeInternal$1$$anonfun$apply$2.apply(TableWriter.scala:234) ~[spark-cassandra-connector_2.11-2.3.1.jar:2.3.1]
        at com.datastax.spark.connector.writer.TableWriter$$anonfun$writeInternal$1$$anonfun$apply$2.apply(TableWriter.scala:233) ~[spark-cassandra-connector_2.11-2.3.1.jar:2.3.1]
        at scala.collection.Iterator$class.foreach(Iterator.scala:893) ~[scala-library-2.11.8.jar:?]

代码片段。

<dependency>
            <groupId>org.apache.spark</groupId>
            <artifactId>spark-sql_2.11</artifactId>
            <version>2.3.1</version>
        </dependency>
        <dependency>
            <groupId>org.apache.spark</groupId>
            <artifactId>spark-core_2.11</artifactId>
            <version>2.3.1</version>
        </dependency>
        <dependency>
            <groupId>com.datastax.spark</groupId>
            <artifactId>spark-cassandra-connector_2.11</artifactId>
            <version>2.3.1</version>
        </dependency>
        <dependency>
            <groupId>com.datastax.cassandra</groupId>
            <artifactId>cassandra-driver-mapping</artifactId>
            <version>3.2.0</version>
        </dependency>

您可以帮助解决此问题吗？预先感谢。

Answer 1

这只有在包含Java驱动程序的非阴影版本时才能发生。由于Guava不兼容，我们需要在Spark Cassandra连接器中遮挡Java驱动程序。这意味着任何其他基于Java驱动程序的库将破坏阴影并引起反射错误，例如上面的错误。

如果您需要手动对Java驱动程序版本做某事，请使用Spark Cassandra Connector的未阴影版本，包括您自己的库，然后再次Shade Guava。