cassandra - Astyanax：如何插入复合列？

Question

我对 astyanax 很陌生，我用谷歌搜索过，找不到插入复合列的简单示例。谁能提供一个简单的例子？例如复合列类型为 Long:Long:Long 为 123:122:233，值为字符串“测试字符串”。提前谢谢。

Answer 1

我会尝试下载源代码并查看单元测试。至少有一项测试可以证明这一点。查看源代码后，您就会明白为什么我推荐该路线而不是仅发布代码片段。它涵盖了相当数量。

Answer 2

尝试这个：

//First you need an object.

// Annotated composite class
public class SessionEvent{
  @Component(ordinal=0) long sessiondId;
  @Component(ordinal=1) long timestamp;
  @Component(ordinal=2) long userId;

  // Must have public default constructor
  public SessionEvent() {
  }
  // ...
  // Don't forget to implement hashcode and equals and a constructor that accepts (long, long, long)

}

//... 
static AnnotatedCompositeSerializer<SessionEvent> eventSerializer
      = new AnnotatedCompositeSerializer<SessionEvent>(SessionEvent.class);
static ColumnFamily<String, SessionEvent> CF_SESSION_EVENTS
      = new ColumnFamily<String, SessionEvent>("SessionEvents",
            StringSerializer.get(), eventSerializer);

//...           
CompositeColumn cc = new SessionEvent("123","456","789"); // Column values  
keyspace.prepareColumnMutation(CF_SESSION_EVENTS, "row key goes here", cc)
    .putValue("this is the value", null)
    .execute();