Test JmsFailoverWatchdog terminal-handler firing on failover give-up

JmsFailoverWatchdogTest spins up an embedded ActiveMQ BrokerService on a
random TCP port, opens a connection through a tightly-bounded failover
URL (maxReconnectAttempts=2, 50ms initial / 100ms max backoff), attaches
a watchdog with a CountDownLatch terminal handler, stops the broker, and
asserts the latch fires within 10s. Tagged Fast; runs in ~0.7s.

Validates that JmsFailoverWatchdog.attach correctly registers with
ActiveMQConnection and that the injected Runnable runs when the failover
transport reports a terminal IOException — without killing the test JVM
via the production System.exit handler.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: jcschaff

vcell-server/src/test/java/cbit/vcell/message/jms/JmsFailoverWatchdogTest.java

@@ -0,0 +1,58 @@
+package cbit.vcell.message.jms;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+import javax.jms.Connection;
+
+import org.apache.activemq.ActiveMQConnectionFactory;
+import org.apache.activemq.broker.BrokerService;
+import org.apache.activemq.broker.TransportConnector;
+import org.junit.jupiter.api.Tag;
+import org.junit.jupiter.api.Test;
+
+@Tag("Fast")
+public class JmsFailoverWatchdogTest {
+
+	/**
+	 * Spin up an embedded broker, attach the watchdog to a connection backed by
+	 * a tightly-bounded failover URL, then stop the broker. After the failover
+	 * transport exhausts its reconnect budget, the TransportListener fires with
+	 * an IOException and the watchdog should run the injected terminal handler.
+	 */
+	@Test
+	public void attach_firesTerminalHandlerWhenFailoverGivesUp() throws Exception {
+		BrokerService broker = new BrokerService();
+		broker.setPersistent(false);
+		broker.setUseJmx(false);
+		broker.setUseShutdownHook(false);
+		TransportConnector connector = broker.addConnector("tcp://localhost:0");
+		broker.start();
+		broker.waitUntilStarted();
+		int port = connector.getConnectUri().getPort();
+
+		String url = "failover:(tcp://localhost:" + port + ")"
+				+ "?maxReconnectAttempts=2"
+				+ "&startupMaxReconnectAttempts=-1"
+				+ "&initialReconnectDelay=50"
+				+ "&maxReconnectDelay=100";
+		ActiveMQConnectionFactory factory = new ActiveMQConnectionFactory(url);
+		Connection connection = factory.createConnection();
+		try {
+			CountDownLatch terminal = new CountDownLatch(1);
+			new JmsFailoverWatchdog(terminal::countDown).attach(connection);
+			connection.start();
+
+			broker.stop();
+			broker.waitUntilStopped();
+
+			assertTrue(terminal.await(10, TimeUnit.SECONDS),
+					"watchdog terminal handler should fire after maxReconnectAttempts exhausted");
+		} finally {
+			try { connection.close(); } catch (Exception ignored) {}
+			try { broker.stop(); } catch (Exception ignored) {}
+		}
+	}
+}