我想使用昆德拉框架将一个对象插入cassandra，但收到以下错误：

java.lang.RuntimeException: java.lang.ClassCastException: java.lang.String cannot be cast to [B
        at org.apache.storm.utils.DisruptorQueue.consumeBatchToCursor(DisruptorQueue.java:448) ~[storm-core-1.0.0.jar:1.0.0]
        at org.apache.storm.utils.DisruptorQueue.consumeBatchWhenAvailable(DisruptorQueue.java:414) ~[storm-core-1.0.0.jar:1.0.0]
        at org.apache.storm.disruptor$consume_batch_when_available.invoke(disruptor.clj:73) ~[storm-core-1.0.0.jar:1.0.0]
        at org.apache.storm.daemon.executor$fn__8226$fn__8239$fn__8292.invoke(executor.clj:851) ~[storm-core-1.0.0.jar:1.0.0]
        at org.apache.storm.util$async_loop$fn__554.invoke(util.clj:484) [storm-core-1.0.0.jar:1.0.0]
        at clojure.lang.AFn.run(AFn.java:22) [clojure-1.7.0.jar:?]
        at java.lang.Thread.run(Thread.java:745) [?:1.7.0_99]
Caused by: java.lang.ClassCastException: java.lang.String cannot be cast to [B
        at org.apache.storm.tuple.TupleImpl.getBinaryByField(TupleImpl.java:185) ~[storm-core-1.0.0.jar:1.0.0]
        at connector.bolt.PrinterBolt.execute(PrinterBolt.java:59) ~[Zorro-0.0.1-SNAPSHOT-jar-with-dependencies.jar:?]
        at org.apache.storm.daemon.executor$fn__8226$tuple_action_fn__8228.invoke(executor.clj:731) ~[storm-core-1.0.0.jar:1.0.0]
        at org.apache.storm.daemon.executor$mk_task_receiver$fn__8147.invoke(executor.clj:463) ~[storm-core-1.0.0.jar:1.0.0]
        at org.apache.storm.disruptor$clojure_handler$reify__7663.onEvent(disruptor.clj:40) ~[storm-core-1.0.0.jar:1.0.0]
        at org.apache.storm.utils.DisruptorQueue.consumeBatchToCursor(DisruptorQueue.java:435) ~[storm-core-1.0.0.jar:1.0.0]
        ... 6 more

我的实体类

@Entity
@Table(name = "pieces", schema = "piece@cassandra_pu")
public class PieceEntitie implements Serializable{

    @Id private String IdPiece;
    @Column private double width;
    @Column private double height;
    @Column private double depth;
    public PieceEntitie() {
        // TODO Auto-generated constructor stub
    }
.
.
.
}

我遵循了教程：https://github.com/impetus-opensource/kundera/wiki/getting-started-in-5-minutes
你知道这个问题的根源吗？我们怎样才能解决它？谢谢您