Most examples are implemented as unit tests so this will actually run the examples. Note that Atomikos is an embedded transaction manager: there is no separate transaction manager service to start because it runs inside your application's JVM. For the demos implemented as unit tests, the transaction manager is started (and stopped) in the test execution.
Some users have reported this error:
[ERROR] Failed to execute goal on project examples-...: Could not resolve dependencies for project ... Authentication failed for http://www.atomikos.com/maven-repository/com/atomikos/... 401 Unauthorized -> [Help 1]
This can be fixed by issuing the following maven command instead:
mvn install --legacy-local-repository
Some examples need to start one or more services to run, and cannot easily be implemented as simple unit tests. These cases contain specific instructions in a README file, in particular for examples that require remoting and/or a separate DBMS server.