Why would someone use Collections.emptyList in java? [duplicate]

Answer 1

Say you have to return a collection and you don't want to creating a couple of objects each time.

interface Configurable {
    List getConfigurationList();
}

// class which doesn't have any configuration
class SimpleConfigurable implements Configurable {
    public List getConfigurationList() { return Collections.emptyList(); }
}

Returning an empty collection is often preferable to returning null