jaxrs/src/main/java/org/jboss/as/jaxrs/deployment/JaxrsDeploymentMarker.java
public static boolean isJaxrsDeployment(DeploymentUnit deploymentUnit) {
        DeploymentUnit deployment = deploymentUnit.getParent() == null ? deploymentUnit : deploymentUnit.getParent();
        Boolean val = deployment.getAttachment(ATTACHMENT_KEY);
        return val != null && val;
    }
public static boolean isJaxrsDeployment(DeploymentUnit deploymentUnit) {
        DeploymentUnit deployment = deploymentUnit.getParent() == null ? deploymentUnit : deploymentUnit.getParent();
        Boolean val = deployment.getAttachment(ATTACHMENT_KEY);
        return val != null && val;
    }
JAX-RS annotations are found in the deployment, especially if it's an EAR one)