Does java.util.List.isEmpty() check if the list itself is null?

I would recommend using Apache Commons Collections:

https://commons.apache.org/proper/commons-collections/apidocs/org/apache/commons/collections4/CollectionUtils.html#isEmpty-java.util.Collection-

which implements it quite ok and well documented:

/**
 * Null-safe check if the specified collection is empty.
 * <p>
 * Null returns true.
 *
 * @param coll  the collection to check, may be null
 * @return true if empty or null
 * @since Commons Collections 3.2
 */
public static boolean isEmpty(Collection coll) {
    return (coll == null || coll.isEmpty());
}

You're trying to call the isEmpty() method on a null reference (as List test = null;). This will surely throw a NullPointerException. You should do if(test!=null) instead (checking for null first).

The method isEmpty() returns true, if an ArrayList object contains no elements; false otherwise (for that the List must first be instantiated that is in your case is null).

You may want to see this question.