Question

我是cassandra的新手，和docker一样。我的目标是从java连接到在docker中运行的cassandra。我正在使用Windows机器

我通过执行cassandra（也尝试过ver 2.2,2.10而没有任何env.variables）

docker run --name cassandra -d -e CASSANDRA_RPC_ADDRESS=127.0.0.1 cassandra:3.0

目前我有这样的docker ps输出：

CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                                         NAMES

f932d3e7e0dc        cassandra:3.0       "/docker-entrypoin..."   5 seconds ago       Up 5 seconds        7000-7001/tcp, 7199/tcp, 9042/tcp, 9160/tcp   cassandra

我可以用这样的输出“docker exec -it cassandra cqlsh”

Connected to Test Cluster at 127.0.0.1:9042.
[cqlsh 5.0.1 | Cassandra 3.0.13 | CQL spec 3.4.0 | Native protocol v4]

在java项目中，我有gradle依赖

compile group: 'com.datastax.cassandra', name: 'cassandra-driver-core', version: '3.2.0'

我的测试代码（也未尝试指定任何协议版本，尝试使用V5）

public static void main(String[] args)
{
  Cluster cluster = Cluster.builder()
                           .addContactPoint("127.0.0.1")
                           .withProtocolVersion(ProtocolVersion.V4)
                           .build();
  Session session = cluster.connect();
}

我得到了这个例外：

Exception in thread "main" com.datastax.driver.core.exceptions.NoHostAvailableException: All host(s) tried for query failed (tried: /127.0.0.1:9042 (com.datastax.driver.core.exceptions.TransportException: [/127.0.0.1:9042] Cannot connect))
    at com.datastax.driver.core.ControlConnection.reconnectInternal(ControlConnection.java:232)
    at com.datastax.driver.core.ControlConnection.connect(ControlConnection.java:79)
    at com.datastax.driver.core.Cluster$Manager.negotiateProtocolVersionAndConnect(Cluster.java:1600)
    at com.datastax.driver.core.Cluster$Manager.init(Cluster.java:1518)
    at com.datastax.driver.core.Cluster.init(Cluster.java:159)
    at com.datastax.driver.core.Cluster.connectAsync(Cluster.java:330)
    at com.datastax.driver.core.Cluster.connectAsync(Cluster.java:305)
    at com.datastax.driver.core.Cluster.connect(Cluster.java:247)
    at com.iter.cassandratest.Cassandratest.main(Cassandratest.java:17)

我做错了什么想法？

编辑1：

根据Cassandra documentation

，我刚尝试使用-P选项运行

现在ps输出为：

CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                                                                                                                         NAMES

9eb54421aac2        cassandra:3.0       "/docker-entrypoin..."   4 seconds ago       Up 3 seconds        0.0.0.0:32772->7000/tcp, 0.0.0.0:32771->7001/tcp, 0.0.0.0:32770->7199/tcp, 0.0.0.0:32769->9042/tcp, 0.0.0.0:32768->9160/tcp   cassandra

我将代码更改为

Cluster cluster = Cluster.builder()
                             .addContactPoint("127.0.0.1")
                             .withPort(32769)
                             .withProtocolVersion(ProtocolVersion.V4)
                             .build();

异常更改为

All host(s) tried for query failed (tried: /127.0.0.1:32769 (com.datastax.driver.core.exceptions.TransportException: [/127.0.0.1:32769]     
Channel has been closed))

Answer 1

如果您想使用默认端口连接到localhost，则需要转发它。

PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>

SELECT DISTINCT  ?concept ?subClassOf
WHERE
{ GRAPH <http://bioportal.bioontology.org/ontologies/RADLEX_OWL>
  { ?term  a <http://bioontology.org/projects/ontologies/radlex/radlexOwl#radlex_metaclass> ;
        <http://bioontology.org/projects/ontologies/radlex/radlexOwl#Preferred_name>  ?concept
  }
  ?term rdfs:subClassOf ?upperClass. 
  ?upperClass <http://bioontology.org/projects/ontologies/radlex/radlexOwl#Preferred_name>  ?subClassOf.
} LIMIT 10 OFFSET 10

使用docker run --name cassandra -d \ -p 9042:9042 \ cassandra:3.0将根据Dockerfile的-P选项为您选择随机端口。

Answer 2

感谢Rober。答案是

docker run --name cassandra -P -d cassandra:3.0

然后连接到docker ps中显示的端口（对我来说是32769）。

Java连接到在docker中运行的cassandra

2 个答案: