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)
for i, m in enumerate(event_source_mappings):
        if uuid_value == m['UUID']:
            return event_source_mappings.pop(i)
    return {}
def use_docker():
    global DO_USE_DOCKER
    if DO_USE_DOCKER is None:
        DO_USE_DOCKER = False
        if 'docker' in config.LAMBDA_EXECUTOR:
            try:
                run('docker images', print_error=False)
                DO_USE_DOCKER = True
            except Exception:
                pass
    return DO_USE_DOCKER
def process_apigateway_invocation(func_arn, path, payload, headers={},
        resource_path=None, method=None, path_params={},
        query_string_params={}, request_context={}):
    try:
        resource_path = resource_path or path
        event = {
            'path': path,
            'headers': dict(headers),
            'pathParameters': dict(path_params),
            'body': payload,