表

//List 接口public interface List<AnyType> extends Collection<AnyType>{    AnyType get(int idx);    AnyType set(int idx, AnyType newVal);    void add(int idx, AnyType x);    void remove(int idx);    ListIterator<AnyType> listIterator(int pos);}

//ArrayList类的实现public class MyArrayList<AnyType> implements Iterable<AnyType> {private static final int DEFAULT_CAPACITY = 10;private int theSize;private AnyType[] theItems;public MyArrayList(){clear();}public void clear(){theSize = 0;ensureCapacity(DEFAULT_CAPACITY);}public int size(){return theSize;}public boolean isEmpty(){return size()==0;}public void trimToSize(){ensureCapacity(size());}public AnyType get(int idx){if(idx < 0 || idx >= size()){throw new ArrayIndexOutOfBoundsException();}return theItems[idx];}public AnyType set(int idx, AnyType newVal){if(idx < 0 || idx >=size()){throw new ArrayIndexOutOfBoundsException();}AnyType old = theItems[idx];theItems[idx] = newVal;return old;}public void ensureCapacity(int newCapacity){if(newCapacity < theSize){return;}AnyType[] old = theItems;//创建一个泛型类型限界的数组，然后使用一个数组进行类型转换//这将产生一个编译器警告，但在泛型集合的实现中是不可避免的theItems = (AnyType[])new Object[newCapacity];for(int i = 0; i < size(); i++){theItems[i] = old[i];}}public boolean add(AnyType x){add(size(), x);return true;}public void add(int idx, AnyType x){if(theItems.length == size()){ensureCapacity(size()*2 + 1);}for(int i = theSize; i > idx; i--){theItems[i] = theItems[i-1];}theItems[idx] = x;theSize++;}public AnyType remove(int idx){AnyType removedItem = theItems[idx];for(int i = idx; i<size()-1; i++){theItems[i] = theItems[i+1];}theSize--;return removedItem;}public java.util.Iterator<AnyType> iterator(){return new ArrayListIterator();}//private class ArrayListIterator implements java.util.Iterator<AnyType>{private int current = 0;public boolean hasNext(){return current < size();}public AnyType next(){if(!hasNext()){throw new java.util.NoSuchElementException();}return theItems[current++];}public void remove(){MyArrayList.this.remove(--current);}}}

//LinkedList类的实现public class MyLinkedList<AnyType> implements Iterable<AnyType>{//节点内部类private static class Node<AnyType>{public Node(AnyType d, Node<AnyType> p, Node<AnyType> n){data = d; prev = p; next = n;}public AnyType data;public Node<AnyType> prev;public Node<AnyType> next;}//构造器public MyLinkedList(){clear();}public void clear(){beginMarker = new Node<AnyType>(null, null, null);endMarker = new Node<AnyType>(null, beginMarker, null);beginMarker.next = endMarker;theSize = 0;modCount++;}public int size(){return theSize;}public boolean isEmpty(){return size() == 0;}public boolean add(AnyType x){add(size(), x);return true;}public void add(int idx, AnyType x){addBefore(getNode(idx), x);}public AnyType get(int idx){return getNode(idx).data;}public AnyType set(int idx, AnyType newVal){Node<AnyType> p = getNode(idx);AnyType oldVal = p.data;p.data = newVal;return oldVal;}public AnyType remove(int idx){return remove(getNode(idx));}private void addBefore(Node<AnyType> p, AnyType x){Node<AnyType> newNode = new Node<AnyType>(x, p.prev, p);newNode.prev.next = newNode;p.prev = newNode;theSize++;modCount++}private AnyType remove(Node<AnyType> p){p.next.prev = p.prev;p.prev.next = p.next;theSize--;modCount++;return p.data;}//私有方法，如果索引表示该表前半部分的一个节点，那么以向后的方向遍历该链表，否则，从终端开始向回遍历private Node<AnyType> getNode(int idx){Node<AnyType> p;if(idx < 0 || idx > size()){throw new IndexOutOfBoundsException();}if(idx < size()/2){p = beginMarker.next;for(int i = 0; i < idx; i++){p = p.next;}}else{p = endMarker;for(int i = size(); i > idx; i--){p = p.prev;}}return p;}public java.util.Iterator<AnyType> iterator(){return new LinkedListIterator();}private class LinkedListIterator implements java.util.Iterator<AnyType>{private Node<AnyType> current = beginMarker.next;private int expectedModCount = modCount;private boolean okToRemove = false;public boolean hasNext(){return current != endMarker;}public AnyType next(){if(modCount != expectedModCount){throw new java.util.ConcurrentModificationException();}if(!hasNext()){throw new java.util.NoSuchElementException();}AnyType nextItem = current.data;current = current.next;okToRemove = true;return nextItem;}public void remove(){if(modCount != expectedModCount){throw new java.util.ConcurrentModificationException();}if(!okToRemove){throw new IllegalStateException();}MyLinkedList.this.remove(current.prev);okToRemove = false;expectedModCount++;}}private int theSize;private int modCount = 0;private Node<AnyType> beginMarker;private Node<AnyType> endMarker;}