表，单链表，双链表

表

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() {        // TODO Auto-generated method stub        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) {        // TODO Auto-generated method stub        if(newCapacity<theSize){            return;        }        AnyType[] old=theItems;        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 void addAll(Iterable<?extends AnyType> items){        Iterator<? extends AnyType> iter=items.iterator();        while(iter.hasNext()){            add(iter.next());        }    }    public void removeAll(Iterable<?extends AnyType> items){        AnyType item,element;        Iterator<? extends AnyType> iter=items.iterator();        while(iter.hasNext()){            item=iter.next();            Iterator<? extends AnyType> iterList=iterator();            while(iterList.hasNext()){                element=iterList.next();                if(element.equals(item))                    iterList.remove();            }        }    }    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;    }    @Override    public java.util.Iterator<AnyType> iterator(){        return new ArrayListIterator();    }    public 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);        }    }}

单链表

public class SingleList {    SingleList(){        init();    }    boolean add(Object x){        if(contains(x))            return false;        else{            Node<Object> p=new Node<Object>(x);            p.next=head.next;            head.next=p;            theSize++;        }        return true;    }    boolean remove(Object x){        if(!contains(x)) return false;        else{            Node<Object> p=head.next;            Node<Object> trailer=head;            while(!p.data.equals(x)){                trailer=p;                p=p.next;            }            trailer.next=p.next;            theSize--;        }        return true;    }    int size(){        return theSize;    }    void print(){        Node<Object> p=head.next;        while(p!=null){            System.out.println(p.data+" ");            p=p.next;        }        System.out.println();    }    boolean contains(Object x){        Node<Object> p=head.next;        while(p!=null){            if(x.equals(p.data))                return true;            else                p=p.next;        }        return false;    }    void init(){        theSize=0;        head=new Node<Object>();        head.next=null;    }    private Node<Object> head;    private int theSize;    private class Node<Object>{        Object data;        Node next;        Node(){            this(null,null);        }        Node(Object d){            this(d,null);        }        Node(Object d, Node n) {            // TODO Auto-generated constructor stub            data=d;            next=n;        }    }}

双链表

public class MyLinkedList<AnyType> implements Iterable<AnyType> {    private int theSize;    private int modCount=0;    private Node<AnyType> beginMarker;    private Node<AnyType> endMarker;    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;    }    public MyLinkedList(){        clear();    }    /*     * Change the size of this collection to zero     */    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));    }    /*     * add an item to this collection ,at specified position p     */    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++;    }    /*     * Removes the object containted in Node p     */    private AnyType remove(Node<AnyType> p){        p.next.prev=p.prev;        p.prev.next=p.next;        theSize--;        modCount++;        return p.data;    }    /*     * Gets the Node at position idx,which must range from 0 to size()     */    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 boolean contains(AnyType x){        Node<AnyType> p=beginMarker.next;        while(p!=endMarker&&!(p.data.equals(x))){            p=p.next;        }        return (p!=endMarker);    }    @Override    public Iterator<AnyType> iterator() {        // TODO Auto-generated method stub        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++;        }    }}