Cluster Execution
Flink programs can run distributed on clusters of many machines. Thereare two ways to send a program to a cluster for execution:
Command Line Interface
The command line interface lets you submit packaged programs (JARs) to a cluster(or single machine setup).
Please refer to the Command Line Interface documentation fordetails.
Remote Environment
The remote environment lets you execute Flink Java programs on a clusterdirectly. The remote environment points to the cluster on which you want toexecute the program.
Maven Dependency
If you are developing your program as a Maven project, you have to add theflink-clients
module using this dependency:
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-clients_2.11</artifactId>
<version>1.10.0</version>
</dependency>
Example
The following illustrates the use of the RemoteEnvironment
:
public static void main(String[] args) throws Exception {
ExecutionEnvironment env = ExecutionEnvironment
.createRemoteEnvironment("flink-master", 8081, "/home/user/udfs.jar");
DataSet<String> data = env.readTextFile("hdfs://path/to/file");
data
.filter(new FilterFunction<String>() {
public boolean filter(String value) {
return value.startsWith("http://");
}
})
.writeAsText("hdfs://path/to/result");
env.execute();
}
Note that the program contains custom user code and hence requires a JAR file withthe classes of the code attached. The constructor of the remote environmenttakes the path(s) to the JAR file(s).