val CF_USER_STATS = new ColumnFamily[java.lang.Long, String]("Standard2", LongSerializer.get, StringSerializer.get)
val m: MutationBatch = keyspace.prepareMutationBatch()
m.withRow(CF_USER_STATS, "acct1234").incrementCounterColumn("CounterColumn1", 1)
m.execute()上面创建了一个列族，在cassandra中用作计数器。无论出于何种原因，编译失败的原因如下：
type mismatch;
[error] found : com.netflix.astyanax.model.ColumnFamily[Long,String]
[error] required: com.netflix.astyanax.model.ColumnFamily[Comparable[_ >: String with Long <: Comparable[_ >: String with Long <: Comparable[_ >: String with Long <: java.io.Serializable] with java.io.Serializable] with java.io.Serializable] with java.io.Serializable,String]
[error] Note: Long <: Comparable[_ >: String with Long <: Comparable[_ >: String with Long <: Comparable[_ >: String with Long <: java.io.Serializable] with java.io.Serializable] with java.io.Serializable] with java.io.Serializable, but Java-defined class ColumnFamily is invariant in type K.
[error] You may wish to investigate a wildcard type such as `_ <: Comparable[_ >: String with Long <: Comparable[_ >: String with Long <: Comparable[_ >: String with Long <: java.io.Serializable] with java.io.Serializable] with java.io.Serializable] with java.io.Serializable`. (SLS 3.2.10)
[error] m.withRow(CF_USER_STATS, "acct1234")
1条答案
按热度按时间ebdffaop1#
astyanax列族语法及说明
现在在您的例子中，您提到rowkey是long类型，column是string，并且在更新计数器时您使用key作为字符串，这就是为什么类型不匹配的原因。