@Override
    public boolean matches(ConditionContext context, AnnotatedTypeMetadata a) {
      return (!isEmpty(context.getEnvironment().getProperty("zipkin.collector.rabbitmq.addresses"))
        || !isEmpty(context.getEnvironment().getProperty("zipkin.collector.rabbitmq.uri"))) &&
        notFalse(context.getEnvironment().getProperty("zipkin.collector.rabbitmq.enabled"));
    }
This condition passes when {@link ZipkinRabbitMQCollectorProperties#getAddresses()} or {@link
ZipkinRabbitMQCollectorProperties#getUri()} is set to a non-empty value.

<p>This is here because the yaml defaults this property to empty like this, and Spring Boot
doesn't have an option to treat empty properties as unset.

<pre>{@code
addresses: ${RABBIT_ADDRESSES:}
uri: ${RABBIT_URI:}
}</pre>
zipkin-server/src/main/java/zipkin2/server/internal/rabbitmq/ZipkinRabbitMQCollectorConfiguration.java