/*** 单链表节点类* @param <T>*/
class Node<T extends Object>{protected T value;protected Node next;
}/** * 单链表类* @param <T>*/
public class ChainList<T extends Object>{private Node<T> first;public void addTail(T t){Node<T> newNode=new Node<T>();newNode.value=t;if(first==null){                        first=newNode;}else{Node<T> curr=first;while(curr.next!=null){curr=curr.next;}curr.next=newNode;}}public void addHead(T t){Node<T> newNode=new Node<T>();newNode.value=t;newNode.next=first;first=newNode;}public int size(){int size=0;Node<T> curr=first;while(curr!=null){size++;curr=curr.next;}return size;}public T get(int index){if(index<0){throw new IllegalArgumentException("下标不能是负数");}else{Node<T> curr=first;while(curr!=null){                if(index==0){return curr.value;}index--;curr=curr.next;}throw new NullPointerException();}}public void remove(int index){if(index<0){throw new IllegalArgumentException("下标不能是负数");}else{if(index==0){Node<T> next=first.next;                first=next;}else{            Node<T> curr=first;Node<T> prev=curr;while(curr!=null){                if(index==0){prev.next=curr.next;return;}index--;prev=curr;curr=curr.next;}throw new NullPointerException();}}}public void display(){System.out.print("链表元素有");Node<T> curr=first;while(curr!=null){System.out.print(curr.value+",");curr=curr.next;}System.out.println();}public static void main(String[] args){ChainList<String> ls=new ChainList<String>();ls.addTail("A");ls.addTail("B");ls.addTail("C");ls.display();ls.addHead("1");ls.display();System.out.println("数组长度为:"+ls.size());System.out.println("第三个元素为:"+ls.get(2));for(int i=0;i<ls.size();i++){System.out.println("第"+(i+1)+"个元素为:"+ls.get(i));}ls.addTail("E");ls.addTail("F");ls.remove(0);        ls.display();ls.remove(1);        ls.display();ls.remove(ls.size()-1);        ls.display();for(int i=0;i<ls.size();i++){System.out.println("第"+(i+1)+"个元素为:"+ls.get(i));}}
}

链表元素有A,B,C,
链表元素有1,A,B,C,
数组长度为:4
第三个元素为:B
第1个元素为:1
第2个元素为:A
第3个元素为:B
第4个元素为:C
链表元素有A,B,C,E,F,
链表元素有A,C,E,F,
链表元素有A,C,E,
第1个元素为:A
第2个元素为:C
第3个元素为:E