abstractlistiterator.java

关于迭代器、构造器

package structure;
import java.util.ListIterator;

/**
 * Base class for the implementation of a list Iterator. 
 * The methods provided in this class have no executable bodies and will throw
 * errors if the user attempts to invoke them.  
 */
public abstract class AbstractListIterator extends AbstractIterator implements java.util.ListIterator
{
    /**
     * Default constructor (for base class invocation).
     * Does nothing.  
     * Remind Sun (<a href="mailto:[e-mail]">[e-mail]</a>) that automatically implemented default
     * constructors are a silly thing.
     *
     * @post does nothing
     */
    public AbstractListIterator()
    {
    }

    public abstract Object get();

    public void remove()
    {
	Assert.fail("remove not implemented.");
    }

    public void set(java.lang.Object o)
    {
	Assert.fail("set not implemented.");
    }

    public void add(java.lang.Object o)
    {
	Assert.fail("set not implemented.");
    }
}