In the hands-on sessions you will implement Flink programs using various Flink APIs. You will also learn how to package a Flink program using Apache Maven and execute the packaged program on a running Flink instance.
The following steps guide you through the process of using the provided data streams, implementing your first Flink streaming program, and packaging and executing your program on a running Flink instance.
1. Learn about the data
The initial set of exercises are all based on data streams of events about taxi rides and taxi fares. These streams are produced by source functions which reads data from input files. Please read these instructions to learn how to use them.
After downloading the datasets, open the
com.ververica.flinktraining.exercises.datastream_java.utils.ExerciseBase class in your IDE, and edit these two lines to point to the two taxi ride data files you have downloaded:
public final static String pathToRideData = "/Users/david/stuff/flink-training/trainingData/nycTaxiRides.gz"; public final static String pathToFareData = "/Users/david/stuff/flink-training/trainingData/nycTaxiFares.gz";
3. Run and debug Flink programs in your IDE
Flink programs can be executed and debugged from within an IDE. This significantly eases the development process and provides an experience similar to working on any other Java (or Scala) application.
Starting a Flink program in your IDE is as easy as running its
main() method. Under the hood, the execution environment will start a local Flink instance within the same process. Hence it is also possible to put breakpoints in your code and debug it.
Assuming you have an IDE with the flink-training-exercises project imported, you can run (or debug) a simple streaming job as follows:
- Open the
com.ververica.flinktraining.examples.datastream_java.basics.RideCountclass in your IDE
- Run (or debug) the
main()method of the
RideCountExampleclass using your IDE.
4. Exercises, Tests, and Solutions
Many of these exercises include an Exercise class with most of the necessary boilerplate code for getting started, as well as a JUnit Test class with tests that will fail until you implement a proper solution, and a Solution class with a complete solution.
Now you are ready to begin with the first exercise.