标签：queue empty pre 参考 push count list package 数据
LinkList:java中jdk1.6之后java.util.LinkList 类中对分装链表的理解：
参考：http://www.cnblogs.com/lintong/p/4374292.html
第一部分：熟悉LinkList中哪些方法和其构造;第二部分熟悉使用JDK中LinkList的API接口
第1部分：LinkList 的介绍：
linklist：是一个双向链表，当做堆栈，队列或者双端队列进行操作；当做stack时候只能用push，pop，peek方法；当做队列时候用 add,remove,element方法
实现List接口能对队列操作；实现Deque接口当做双端队列使用；
自己编写的Linklist 与JDK中LinkedList相比较，推荐使用自带的LinkedList
package MyArrayList; public class MyLinkList <AnyType> implements Iterable<AnyType> { //内嵌类node，指向LinkList的头结点(header_node)与尾部结点(tail_node)； //父亲查看私有类的属性，但是外部不知道有这样私有元素 private int theSize; private int modCount=0; private Node<AnyType> beginMaker; private Node<AnyType> endMaker; private static class Node<AnyType> { @SuppressWarnings("unused") public AnyType data; @SuppressWarnings("unused")//你从没有使用这个变量 public Node<AnyType> prev; @SuppressWarnings("unused") public Node<AnyType> next; //构造函数初始化 @SuppressWarnings("unused") public Node(AnyType data,Node<AnyType>p,Node<AnyType>q) { this.data=data; this.prev=p; this.next=q; } } public void cLear() { //申请Node结点同时初始化，后面建立初始链表 doClear(); } private void doClear() { beginMaker=new Node<AnyType>(null,null,null); endMaker=new Node<AnyType>(null,beginMaker,null); beginMaker.next=endMaker; theSize=0; modCount++; } public int size() { return theSize; } public boolean isEmpty() { return size()==0; } public boolean add(AnyType x) {//顺序插入尾部插入 add(size(),x); return true; } public void add(int idx,AnyType x) { //中间插入找到插入结点的位置，双向链表,将数据插入 addBefore(getNode(idx,0,size()),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 AnyType remove(Node<AnyType> p) { p.next.prev=p.prev; p.prev.next=p.next; theSize--; modCount++; return p.data; } private void addBefore ( Node<AnyType> p,AnyType x) { //P的前面插入 Node<AnyType>newNode=new Node<>(x,p.prev,p); p.prev.next=newNode; p.prev=newNode; theSize++; modCount++; } private Node<AnyType> getNode(int idx) { return getNode(idx,0,size()-1); } private Node<AnyType> getNode(int idx,int lower,int upper) { Node<AnyType>p; if(idx<lower || idx> upper) throw new IndexOutOfBoundsException(); if(idx<size()/2) { p=beginMaker.next; for(int i=0;i<idx;i++) p=p.next; } else { p=endMaker; for(int i=size();i>idx;i--) p=p.prev; } return p; } //采用Iterator接口 public java.util.Iterator<AnyType> iterator() { return new LinkedListIterator(); } public class LinkedListIterator implements java.util.Iterator<AnyType> { private Node<AnyType> current =beginMaker.next; private int expectedModCount=modCount;//记录迭代器在迭代的期间被修改的次数 private boolean okToremove=false;//判断是否已经执行移除操作 @Override public boolean hasNext() { // TODO Auto-generated method stub return current!=endMaker ; } @Override public AnyType next() { // TODO Auto-generated method stub 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() { // TODO Auto-generated method stub if(modCount!=expectedModCount) throw new java.util.ConcurrentModificationException(); if(!okToremove) throw new java.util.NoSuchElementException(); MyLinkList.this.remove(current.prev); expectedModCount++; okToremove=false; } } }
使用小程序对上面编写东西进行测试：
package MyArrayList; import 自己包下的MyLinkList import java.util.Iterator; //使用泛型类,实现Iterator的接口，必须实现Iterator中iterator方法 public class MyArrayList <AnyType> implements Iterable<AnyType>{ private static final int DEFAULT_CAPACITY=10;//ArryList中默认的容量10 private int theSize; private AnyType [] theItems;//Number of elements public MyArrayList() {//构造函数初始化 doClear(); } private void doClear() { theSize=0; //开辟一个默认为10的数组 enSureCapacity(DEFAULT_CAPACITY); } /*****为了外部调用内部方法****/ public int size() { return theSize; } public boolean isEmpty() { return size()==0; } public void trimToSize() { enSureCapacity(size()); } @SuppressWarnings("unchecked") public void enSureCapacity(int newCapacity) { if(newCapacity<theSize) return; //如果发现要的容量大于theSize,必须开辟更多空间 AnyType [] old=theItems; theItems=(AnyType[]) new Object[newCapacity]; for(int i=0;i<theSize;i++) theItems[i]=old[i]; } 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;//告诉我们已经完成设置 } public void add(int idx,AnyType x) {//防止是否在数组满情况下相加 if(size()==theItems.length) { enSureCapacity(size()*2+1); } //在idx位置上插入一个数，将idx右侧数据向右边移动，腾出插入位置 for(int i=theSize;i>idx;i--) theItems[i]=theItems[i-1]; theItems[idx]=x; theSize++; } public AnyType remove(int idx) { //与插入相反，将右侧位置覆盖就行 AnyType removeItem=theItems[idx]; for(int i=idx;i<size();i++) theItems[i]=theItems[i++]; theSize--; return removeItem; } //对ArrayList数组数进行遍历： public void access() { AnyType val=null; for(int i=0;i<size();i++) { val=theItems[i]; System.out.print(val+" "); } } //实现Iterator下iterator方法 @Override public java.util.Iterator<AnyType> iterator() { // TODO Auto-generated method stub return new ArrayListIterator(); //这个实列实现Iterator接口 } private class ArrayListIterator implements java.util.Iterator<AnyType> { private int current=0; @Override public boolean hasNext() { // TODO Auto-generated method stub return current<size(); } @Override public AnyType next() { // TODO Auto-generated method stub if(!hasNext()) throw new java.util.NoSuchElementException(); return theItems[current++]; } public void remove() { MyArrayList.this.remove(--current); } } public static void main(String[] args) { MyArrayList<Integer> test=new MyArrayList<Integer>(); test.enSureCapacity(10); test.add(0, 1); test.access(); } }
*****测试自己编写的LinkList********* current val3 push stack top is c After pop 2 pop stack top b *****测试jdk的LinkList********* 2 1 *****测试自己编写的LinkList********* 显示队列中顶元素a 删除队列中元素a 显示队列中顶元素b *****测试jdk的LinkList********* queue.element():20 queue.remove():20
标签：queue empty pre 参考 push count list package 数据
原文地址：http://www.cnblogs.com/woainifanfan/p/6105286.html
