@Override
  public ConditionOutcome getMatchOutcome(ConditionContext aContext, AnnotatedTypeMetadata aMetadata) {
    String property = aContext.getEnvironment().getProperty("piper.worker.enabled");
    boolean result = Boolean.valueOf(property);
    return new ConditionOutcome(result,ConditionMessage.forCondition(ConditionalOnWorker.class, "(" + getClass().getName() + ")").resultedIn(result));
  }
A Condition that evaluates if piper.roles property 
contains the value <code>worker</code>.

@author Arik Cohen
@see ConditionalOnWorker
src/main/java/com/creactiviti/piper/core/annotations/OnWorkerCondition.java