package listFW.factory;

import listFW.*;

/**
 * Concrete IListFactory to manufacture IList objects.  How it does it is
 * completely hidden from all external client code.
 * The Singleton pattern is used ensure there is only one instance of this
 * factory.  This saves time and space.
 * To use this factory, simply call CompositeListFactory.Singleton.
 * @author D.X. Nguyen
 */
public class CompositeListFactory implements IListFactory {

    /**
     * Singleton Design Pattern:
     */
    public static final CompositeListFactory Singleton
                        =  new CompositeListFactory();

    /**
     * private constructor makes it impossible for external code to instantiate
     * any copy of this factory object.  Only the code inside of this class can
     * call this constructor, which is what the above line of code does.
     */
    private CompositeListFactory() {
    }

    // A bunch of code to implement IEmptyList and INEList elided...

    public IEmptyList makeEmptyList() {
        // code elided.
    }

    public INEList makeNEList(Object first, IList tail) {
        // code elided.
    }
}