Running the processing engine

The ProcessingEngine class coordinates the Reader and Writer classes. It contains the main method to coordinate them. Create a new file called ProcessingEngine.java in the src/main/java/monedero/ directory and copy therein the code in Listing 2.8.

The following is the content of Listing 2.8, ProcessingEngine.java:

package monedero;
public class ProcessingEngine {
  public static void main(String[] args) {
    String servers = args[0];
    String groupId = args[1];
    String sourceTopic = args[2];
    String targetTopic = args[3];
    Reader reader = new Reader(servers, groupId, sourceTopic);
    Writer writer = new Writer(servers, targetTopic);
    reader.run(writer);
  }
}

ProcessingEngine receives four arguments from the command line:

• args[0] servers, the host and port of the Kafka broker
• args[1] groupId, the consumer group...