Pub sub does not seem to work with Java 7 because of gRPC/netty stuff

[j256]

Although the docs state that Java 8 is required, this invalidates its use in my corporate code base which is back on Java 7. I do see that the class files are Java 7 compliant however. Is it possible to run under Java 7? Are there versions of the API that work under 7?

[garrettjonesgoogle]

Java 8 is only really required when running under App Engine; otherwise Java 7 is the minimum version ( see https://github.com/GoogleCloudPlatform/google-cloud-java#java-versions ).

[j256]

Sigh. Sorry about that. Not sure where I got Java 8 from. Thanks for the quick response.

[j256]

Although Pub/Sub runs under Java 7, I can't get the following test program to work with version 0.36, 37, or 38. I'm getting the java.lang.ClassNotFoundException: org/eclipse/jetty/alpn/ALPN class not found error but not in the main but deep in netty-land which implies that it is in a different classloader. It runs under Java 8 however so I suspect that maybe a dependency has a requirement? Or maybe this is a security manager issue....

Test program:

public class TestMain {
	public static void main(String[] args) throws Exception {
		Class.forName("org.eclipse.jetty.alpn.ALPN", true, TestMain.class.getClassLoader());
		String projectId = "my-project";
		String topicId = "test-topic";
		String subscriberId = "test-main";
		ProjectSubscriptionName subsciptionName = ProjectSubscriptionName.of(projectId, subscriberId);
		// SubscriptionName subsciptionName = SubscriptionName.of(projectId, subscriberId);
		Builder builder = Subscriber.newBuilder(subsciptionName, new OurReceiver());
		GoogleCredentials credentials = GoogleCredentials.fromStream(new FileInputStream("/tmp/creds.json"));
		builder.setCredentialsProvider(FixedCredentialsProvider.create(credentials));
		Subscriber subscriber = builder.build();
		subscriber.startAsync().awaitRunning();
		subscriber.awaitTerminated(10000000, TimeUnit.MILLISECONDS);
	}
	private static class OurReceiver implements MessageReceiver {
		@Override
		public void receiveMessage(PubsubMessage message, AckReplyConsumer consumer) {
			System.out.println("received message: " + message.getMessageId());
			consumer.ack();
		}
	}
}

My pom is just:

	<dependencies>
		<dependency>
			<groupId>com.google.cloud</groupId>
			<artifactId>google-cloud-pubsub</artifactId>
			<version>0.38.0-beta</version>
		</dependency>
	</dependencies>
	<build>
		<plugins>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<configuration>
					<source>1.7</source>
					<target>1.7</target>
				</configuration>
			</plugin>
		</plugins>
	</build>

[j256]

This looks like a problem with the netty gprc 1.9.0.

[j256]

I'm going to close this because it is an overlap with #3044