The lambda execution is not suspending and the lambda container has no port exposed when running a java 11 lambda with the latest localstack docker image by docker-compose with the environment variable LAMBDA_JAVA_OPTS=-agentlib:jdwp=transport=dt_socket,server=y,suspend=y,address=_debug_port_
    
It works fine for java8 runtime executions.

Docker command:

> localstack_1  | 2020-01-26T12:42:04:INFO:localstack.services.awslambda.lambda_executors: Running lambda cmd: CONTAINER_ID="$(docker create -i   -e ENV="$ENV" -e DOCKER_LAMBDA_USE_STDIN="$DOCKER_LAMBDA_USE_STDIN" -e HOSTNAME="$HOSTNAME" -e LOCALSTACK_HOSTNAME="$LOCALSTACK_HOSTNAME" -e AWS_LAMBDA_FUNCTION_TIMEOUT="$AWS_LAMBDA_FUNCTION_TIMEOUT" -e AWS_LAMBDA_FUNCTION_NAME="$AWS_LAMBDA_FUNCTION_NAME" -e AWS_LAMBDA_FUNCTION_VERSION="$AWS_LAMBDA_FUNCTION_VERSION" -e AWS_LAMBDA_FUNCTION_INVOKED_ARN="$AWS_LAMBDA_FUNCTION_INVOKED_ARN"  --rm "lambci/lambda:java11" "com.XXX.XXX.Handler")";docker cp "/tmp/localstack/zipfile.0c90736c/." "$CONTAINER_ID:/var/task"; docker start -ai "$CONTAINER_ID";

I think this is due to the fact that the classpath arguments and java opts are only being set if the rutime is equal to LAMBDA_RUNTIME_JAVA8 (line 211 of ocalstack/localstack/services/awslambda/lambda_executors.py , commit 03c6f4bf250edd18eb818ed65090f508636b0bff)
self.next_port = (self.next_port + 1) % self.max_port
        
        LOG.debug('Priming docker container with runtime "%s" and arn "%s".', runtime, func_arn)
        container_info = self.prime_docker_container(runtime, func_arn, env_vars.items(), lambda_cwd)
        
        
        
        exec_env_vars = ' '.join(['-e {}="${}"'.format(k, k) for (k, v) in env_vars.items()])
        if not command:
            command = '%s %s' % (container_info.entry_point, handler)
        
        copy_command = ''
        docker_cmd = self._docker_cmd()
        event_file = os.path.join(lambda_cwd, LAMBDA_EVENT_FILE)
        if not has_been_invoked_before and config.LAMBDA_REMOTE_DOCKER:
            
            copy_command = '%s cp "%s/." "%s:/var/task";' % (docker_cmd, lambda_cwd, container_info.name)
        elif os.path.exists(event_file):
            
            copy_command = '%s cp "%s" "%s:/var/task";' % (docker_cmd, event_file, container_info.name)
        cmd = (
            '%s'
            ' %s exec'
            ' %s'  
            ' %s'  
            ' %s'  
        ) % (copy_command, docker_cmd, exec_env_vars, container_info.name, command)
        LOG.debug('Command for docker-reuse Lambda executor: %s' % cmd)
        return cmd
    def startup(self):