java单向链表

//单向链表

public class SingleLinkedList {

//链表节点的个数

private int size;

//头节点

private Node head;

 

public SingleLinkedList() {

size = 0;

head = null;

}

 

//链表的每个节点类

private class Node {

//每个节点的数据

private Object data;

//每个节点指向下个节点的连接

private Node next;

 

public Node(Object data) {

this.data = data;

}

}

 

//在链表头部添加元素

public Object addHead(Object data) {

Node newNode = new Node(data);

if(size == 0) {

head = newNode;

}else {

newNode.next = head;

head = newNode;

}

size ++;

return data;

}

 

//删除链表头部元素

public Object deleteHead() {

Object data = head.data;

head = head.next;

size -- ;

return data;

}

 

//查找指定元素，找到返回节点Node,找不到返回null

public Node find(Object data) {

Node current = head;

int tempSize = size;

while(tempSize > 0) {

if(data.equals(current.data)) {

return current;

}else {

current = current.next;

}

tempSize -- ;

}

return null;

}

 

//删除指定的元素，删除成功返回true

public boolean delete(Object data) {

if(size == 0) {

return false;

}

Node current = head;

Node previous = head;

while( current.data != data) {

if(current.next == null) {

return false;

}else {

previous = current;

current = current.next;

}

}

//如果删除的是第一个节点

if(current == head) {

head = current.next;

size -- ;

}else {//删除的不是第一个节点

previous.next = current.next;

size -- ;

}

return true;

}

 

//判断链表是否为空

public boolean isEmpty() {

return (size == 0);

 

 

}

 

//显示节点信息

public void display() {

if(size > 0) {

Node node = head;

int tempSize = size;

if(tempSize == 1) {

System.out.print("["+node.data+"]");

return;

}

while(tempSize > 0) {

if(node.equals(head)) {

System.out.print("["+node.data+"->");

}else if(node.next == null) {

System.out.print(node.data+"]");

}else {

System.out.print(node.data+"->");

}

node = node.next;

tempSize --;

}

System.out.println();

}else {

System.out.println("[]");

}

}

}

 

//单向链表实现栈

public class StackSingleLinke {

 

private SingleLinkedList linke;

 

public StackSingleLinke() {

linke = new SingleLinkedList();

}

 

//添加元素

public void push(Object data) {

linke.addHead(data);

}

 

//移除栈顶元素

public Object pop() {

Object obj = linke.deleteHead();

return obj;

}

 

//判断是否为空

public boolean isEmpty() {

return linke.isEmpty();

}

 

//打印栈内元素信息

public void disply() {

linke.display();

}

}

 

 

测试：

public class TestSingleLinkedList {

 

@Test

public void testSingleLinkedList() {

SingleLinkedList singleLinkeList = new SingleLinkedList();

singleLinkeList.addHead("A");

singleLinkeList.addHead("B");

singleLinkeList.addHead("C");

singleLinkeList.addHead("D");

//打印当前列表信息

singleLinkeList.display();

//删除节点C

singleLinkeList.delete("C");

singleLinkeList.display();

//查找B

System.out.println(singleLinkeList.find("B"));

System.out.println(singleLinkeList.isEmpty());

singleLinkeList.deleteHead();

singleLinkeList.display();

}

 

}

 

结果：

[D->C->B->A]

[D->B->A]

practice.com.wzy.singlelinke.SingleLinkedList$Node@4459eb14

false

[B->A]