8

我正在使用 Cassandra-0.8.2。我正在使用最新版本的 Hector & 我的 java 版本是 1.6.0_26

我对 Cassandra & Hector 很陌生。

我正在尝试做的事情： 1. 连接到另一台服务器上正在运行的 cassandra 实例。我知道它正在运行 b/c 我可以通过我的终端 ssh 进入运行这个 Cassandra 实例的服务器并运行具有完整功能的 CLI。2. 然后我想连接到一个键空间并创建一个列族，然后通过 Hector 向该列族添加一个值。

我认为我的问题是此服务器上运行的 Cassandra 实例可能未配置为获取非本地命令。我认为我的下一步将是在我正在处理的 cpu 上添加 Cassandra 的本地实例，并尝试在本地执行此操作。你怎么看？

这是我的Java代码：

import me.prettyprint.cassandra.serializers.StringSerializer;
import me.prettyprint.cassandra.service.CassandraHostConfigurator;
import me.prettyprint.hector.api.Cluster;
import me.prettyprint.hector.api.Keyspace;
import me.prettyprint.hector.api.ddl.ColumnFamilyDefinition;
import me.prettyprint.hector.api.ddl.ComparatorType;
import me.prettyprint.hector.api.factory.HFactory;
import me.prettyprint.hector.api.mutation.Mutator;

    public class MySample {


        public static void main(String[] args) {


            Cluster cluster = HFactory.getOrCreateCluster("Test Cluster", "xxx.xxx.x.41:9160");
            Keyspace keyspace =  HFactory.createKeyspace("apples", cluster);
            ColumnFamilyDefinition cf = HFactory.createColumnFamilyDefinition("apples","ColumnFamily2",ComparatorType.UTF8TYPE);
            StringSerializer stringSerializer = StringSerializer.get();
            Mutator<String> mutator = HFactory.createMutator(keyspace, stringSerializer);
            mutator.insert("jsmith", "Standard1", HFactory.createStringColumn("first", "John"));
}
}

我的错误是：

16:22:19,852  INFO CassandraHostRetryService:37 - Downed Host Retry service started with queue size -1 and retry delay 10s
16:22:20,136  INFO JmxMonitor:54 - Registering JMX me.prettyprint.cassandra.service_Test Cluster:ServiceType=hector,MonitorType=hector
Exception in thread "main" me.prettyprint.hector.api.exceptions.HInvalidRequestException: InvalidRequestException(why:Keyspace apples does not exist)
    at me.prettyprint.cassandra.connection.HThriftClient.getCassandra(HThriftClient.java:70)
    at me.prettyprint.cassandra.connection.HConnectionManager.operateWithFailover(HConnectionManager.java:226)
    at me.prettyprint.cassandra.service.KeyspaceServiceImpl.operateWithFailover(KeyspaceServiceImpl.java:131)
    at me.prettyprint.cassandra.service.KeyspaceServiceImpl.batchMutate(KeyspaceServiceImpl.java:102)
    at me.prettyprint.cassandra.service.KeyspaceServiceImpl.batchMutate(KeyspaceServiceImpl.java:108)
    at me.prettyprint.cassandra.model.MutatorImpl$3.doInKeyspace(MutatorImpl.java:222)
    at me.prettyprint.cassandra.model.MutatorImpl$3.doInKeyspace(MutatorImpl.java:219)
    at me.prettyprint.cassandra.model.KeyspaceOperationCallback.doInKeyspaceAndMeasure(KeyspaceOperationCallback.java:20)
    at me.prettyprint.cassandra.model.ExecutingKeyspace.doExecute(ExecutingKeyspace.java:85)
    at me.prettyprint.cassandra.model.MutatorImpl.execute(MutatorImpl.java:219)
    at me.prettyprint.cassandra.model.MutatorImpl.insert(MutatorImpl.java:59)
    at org.cassandra.examples.MySample.main(MySample.java:25)
Caused by: InvalidRequestException(why:Keyspace apples does not exist)
    at org.apache.cassandra.thrift.Cassandra$set_keyspace_result.read(Cassandra.java:5302)
    at org.apache.cassandra.thrift.Cassandra$Client.recv_set_keyspace(Cassandra.java:481)
    at org.apache.cassandra.thrift.Cassandra$Client.set_keyspace(Cassandra.java:456)
    at me.prettyprint.cassandra.connection.HThriftClient.getCassandra(HThriftClient.java:68)
    ... 11 more

预先感谢您的帮助。

4

2 回答 2

8

The exception you are getting is,

why:Keyspace apples does not exist

In your code, this line does not actually create the keyspace,

Keyspace keyspace =  HFactory.createKeyspace("apples", cluster);

As described here, this is the code you need to define your keyspace,

ColumnFamilyDefinition cfDef = HFactory.createColumnFamilyDefinition("MyKeyspace", "ColumnFamilyName", ComparatorType.BYTESTYPE);

KeyspaceDefinition newKeyspace = HFactory.createKeyspaceDefinition("MyKeyspace", ThriftKsDef.DEF_STRATEGY_CLASS,  replicationFactor, Arrays.asList(cfDef));

// Add the schema to the cluster.
// "true" as the second param means that Hector will block until all nodes see the change.
cluster.addKeyspace(newKeyspace, true);
于 2011-08-05T02:57:08.600 回答
3

我们在 wiki 上也有一个入门指南，这可能会有所帮助。

于 2011-08-05T16:46:26.213 回答