Java in a Nutshell, 5th Edition

Name

AbstractList<E>

Synopsis

This abstract class is a partial implementation of the List interface that makes it easy to define custom List implementations based on random-access list elements (such as objects stored in an array). If you want to base a List implementation on a sequential-access data model (such as a linked list), subclass AbstractSequentialList instead.

To create an unmodifiable List, simply subclass AbstractList and override the (inherited) size( ) and get( ) methods. To create a modifiable list, you must also override set( ) and, optionally, add( ) and remove( ). These three methods are optional, so unless you override them, they simply throw an UnsupportedOperationException. All other methods of the List interface are implemented in terms of size( ), get( ), set( ), add( ), and remove( ). In some cases, you may want to override these other methods to improve performance. By convention, all List implementations should define two constructors: one that accepts no arguments and another that accepts a Collection of initial elements for the list.

Figure 16-2. java.util.AbstractList<E>

public abstract class AbstractList<E> extends AbstractCollection<E> implements List<E> {
// Protected Constructors
     protected AbstractList( );  
// Methods Implementing List
     public boolean add(E o);  
     public void add(int index, E element);  
     public boolean addAll(int index, Collection<? extends ...