We'll start this lesson where we left the previous one. We are providing the Publisher and the RequestBuilderCarrier on the workspace, as there's no need to change anything on them during this lesson, but refer to the previous versions of the Hello client and Formatter when working on this lesson.
Let's add a new parameter to our Hello's main method, so that it accepts a greeting in addition to a name. This is how the main method would look like in the end:
public static void main(String[] args) {
if (args.length != 2) {
throw new IllegalArgumentException("Expecting two arguments, helloTo and greeting");
}
String helloTo = args[0];
String greeting = args[1];
Tracer tracer = Tracing.init("hello-world");
new Hello(tracer).sayHello(helloTo, greeting);
tracer.close();
System.exit(0); // okhttpclient sometimes hangs maven otherwise
}
Don't forget to change the signature of the method sayHello() to accept this new parameter:
private void sayHello(String helloTo, String greeting) {
And add this instruction to sayHello method after starting the span:
scope.span().setBaggageItem("greeting", greeting);
By doing this we read a second command line argument as a "greeting" and store it in the baggage under "greeting" key.
