Amqp utils kung fu

AmqpUtils.java

package net.homecredit.mer.web

import org.springframework.amqp.rabbit.connection.Connection
import org.springframework.amqp.rabbit.connection.ConnectionFactory

import static java.lang.System.currentTimeMillis
import static net.homecredit.mer.web.WaitUtils.doWait
import static org.junit.Assert.fail

class AmqpUtils {

    static void awaitQueueNonEmpty(ConnectionFactory connectionFactory, String queueName, long maxTimeoutMs, long timeoutMs) {
        long start = currentTimeMillis()
        def connection = connectionFactory.createConnection()
        while (!isQueueNonEmpty(connection, queueName) && currentTimeMillis() - start < maxTimeoutMs) {
            doWait(timeoutMs)
        }
        if (!isQueueNonEmpty(connection, queueName)) {
            fail("Queue empty: $queueName. Total waiting time was ~ ${(currentTimeMillis() - start) / 1000} seconds")
        }
        connection.close()
    }

    static boolean isQueueNonEmpty(Connection connection, String queueName) {
        def channel
        try {
            channel = connection.createChannel(false)
            channel.messageCount(queueName) > 0
        } finally {
            if (channel != null) {
                channel.close()
            }
        }
    }
}