我对Java和MongoDB（或任何数据库）都很陌生，我一直在编写这个Java程序来测试连接，它应该只是简单地建立连接并列出所有现有的数据库名称。

import com.mongodb.MongoClient;

import com.mongodb.client.MongoCursor;

public class test {
    public static void main(String[] args) {
        try{
            MongoClient mongoClient = new MongoClient( "localhost" , 27017 );

            MongoCursor<String> dbsCursor = mongoClient.listDatabaseNames().iterator();
            while(dbsCursor.hasNext()) {
                System.out.println(dbsCursor.next());
            }

        }catch(Exception e){
            System.err.println( e.getClass().getName() + ": " + e.getMessage() );
        }
    }
}

MongoDB服务器已经启动，但是当我运行这个应用程序时，它显示了如下错误

Jun 25, 2016 3:35:06 PM com.mongodb.diagnostics.logging.JULLogger log
INFO: Cluster created with settings {hosts=[localhost:27017], mode=SINGLE, requiredClusterType=UNKNOWN, serverSelectionTimeout='30000 ms', maxWaitQueueSize=500}
Jun 25, 2016 3:35:06 PM com.mongodb.diagnostics.logging.JULLogger log
INFO: No server chosen by ReadPreferenceServerSelector{readPreference=primary} from cluster description ClusterDescription{type=UNKNOWN, connectionMode=SINGLE, all=[ServerDescription{address=localhost:27017, type=UNKNOWN, state=CONNECTING}]}. Waiting for 30000 ms before timing out
Jun 25, 2016 3:35:06 PM com.mongodb.diagnostics.logging.JULLogger log
INFO: Exception in monitor thread while connecting to server localhost:27017
com.mongodb.MongoSocketWriteException: Exception sending message
    at com.mongodb.connection.InternalStreamConnection.translateWriteException(InternalStreamConnection.java:462)
    at com.mongodb.connection.InternalStreamConnection.sendMessage(InternalStreamConnection.java:205)
    at com.mongodb.connection.CommandHelper.sendMessage(CommandHelper.java:89)
    at com.mongodb.connection.CommandHelper.executeCommand(CommandHelper.java:32)
    at com.mongodb.connection.InternalStreamConnectionInitializer.initializeConnectionDescription(InternalStreamConnectionInitializer.java:83)
    at com.mongodb.connection.InternalStreamConnectionInitializer.initialize(InternalStreamConnectionInitializer.java:43)
    at com.mongodb.connection.InternalStreamConnection.open(InternalStreamConnection.java:115)
    at com.mongodb.connection.DefaultServerMonitor$ServerMonitorRunnable.run(DefaultServerMonitor.java:128)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.net.SocketException: Software caused connection abort: socket write error
    at java.net.SocketOutputStream.socketWrite0(Native Method)
    at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:109)
    at java.net.SocketOutputStream.write(SocketOutputStream.java:153)
    at com.mongodb.connection.SocketStream.write(SocketStream.java:75)
    at        com.mongodb.connection.InternalStreamConnection.sendMessage(InternalStreamConnection.java:201)
... 7 more

com.mongodb.MongoTimeoutException: Timed out after 30000 ms while waiting for a server that matches ReadPreferenceServerSelector{readPreference=primary}. Client view of cluster state is {type=UNKNOWN, servers=[{address=localhost:27017, type=UNKNOWN, state=CONNECTING, exception={com.mongodb.MongoSocketWriteException: Exception sending message}, caused by {java.net.SocketException: Software caused connection abort: socket write error}}]

Process finished with exit code 0

这意味着什么？我应该设置ReadPreferenceServerSelector吗？但是我在网上找不到任何相关的文档。