Virgin sample project doesn't build

I followed instructions to construct the "echo service" sample project and imported it into
eclipse. It doesn't quite build due to a missing dependency.

Description Resource Path Location Type
ClientManager cannot be resolved EchoTest.java /echo-service/src/test/java/com/example line 36 Java Problem
ClientManager cannot be resolved to a type EchoTest.java /echo-service/src/test/java/com/example line 36 Java Problem
The type org.glassfish.tyrus.client.ClientManager is not accessible EchoTest.java /echo-service/src/test/java/com/example line 14 Java Problem

I'm using eclipse and java 16 on windows.