./bin/flink run examples/streaming/SocketWindowWordCount.jar --port 9000
根据官方的QuickStart直接运行示例程序，请按照以下步骤登录。原因似乎是java.net.ConnectException。我确定未使用端口并且防火墙已关闭。
root@maple-PC:/home/maple/Downloads/flink-1.4.2# ./bin/flink run examples/streaming/SocketWindowWordCount.jar --port 9000
Cluster configuration: Standalone cluster with JobManager at localhost/127.0.0.1:6123
Using address localhost:6123 to connect to JobManager.
JobManager web interface address http://localhost:8081
Starting execution of program
Submitting job with JobID: b371f7847302f8930115f093c7e32d3d. Waiting for job completion.
Connected to JobManager at Actor[akka.tcp://flink@localhost:6123/user/jobmanager#-198847679] with leader session id 00000000-0000-0000-0000-000000000000.
12/15/2018 01:06:20 Job execution switched to status RUNNING.
12/15/2018 01:06:20 Source: Socket Stream -> Flat Map(1/1) switched to SCHEDULED
12/15/2018 01:06:20 TriggerWindow(TumblingProcessingTimeWindows(5000), ReducingStateDescriptor{serializer=org.apache.flink.api.java.typeutils.runtime.PojoSerializer@9cfdeb73, reduceFunction=org.apache.flink.streaming.examples.socket.SocketWindowWordCount$1@71687585}, ProcessingTimeTrigger(), …