Java单链表的实现代码

下面是小编给大家分享的一个使用java写单链表，有问题欢迎给我留言哦。

首先定义一个node类

public class node {
protected node next; //指针域 
public int data;//数据域 

public node( int data) { 
this. data = data; 
} 
//显示此节点 
public void display() { 
system. out.print( data + " "); 
} 
}

接下来定义一个单链表，并实现相关方法：

public class linklist {
public node first; // 定义一个头结点
private int pos = 0;// 节点的位置
public linklist() {
this.first = null;
}
// 插入一个头节点
public void addfirstnode(int data) {
node node = new node(data);
node.next = first;
first = node;
}
// 删除一个头结点,并返回头结点
public node deletefirstnode() {
node tempnode = first;
first = tempnode.next;
return tempnode;
}
// 在任意位置插入节点 在index的后面插入
public void add(int index, int data) {
node node = new node(data);
node current = first;
node previous = first;
while (pos != index) {
previous = current;
current = current.next;
pos++;
}
node.next = current;
previous.next = node;
pos = 0;
}
// 删除任意位置的节点
public node deletebypos(int index) {
node current = first;
node previous = first;
while (pos != index) {
pos++;
previous = current;
current = current.next;
}
if (current == first) {
first = first.next;
} else {
pos = 0;
previous.next = current.next;
}
return current;
}
// 根据节点的data删除节点(仅仅删除第一个)
public node deletebydata(int data) {
node current = first;
node previous = first; // 记住上一个节点
while (current.data != data) {
if (current.next == null) {
return null;
}
previous = current;
current = current.next;
}
if (current == first) {
first = first.next;
} else {
previous.next = current.next;
}
return current;
}
// 显示出所有的节点信息
public void displayallnodes() {
node current = first;
while (current != null) {
current.display();
current = current.next;
}
system.out.println();
}
// 根据位置查找节点信息
public node findbypos(int index) {
node current = first;
if (pos != index) {
current = current.next;
pos++;
}
return current;
}
// 根据数据查找节点信息
public node findbydata(int data) {
node current = first;
while (current.data != data) {
if (current.next == null)
return null;
current = current.next;
}
return current;
}
}

最后我们可以通过测试类来做相关测试:

public class testlinklist {
public static void main(string[] args) { 
linklist linklist = new linklist(); 
linklist.addfirstnode(20); 
linklist.addfirstnode(21); 
linklist.addfirstnode(19); 
//print19,21,20 
linklist.add(1, 22); //print19,22,21,20 
linklist.add(2, 23); //print19,22,23,21,20 
linklist.add(3, 99); //print19,22,23,99,21,20 
//调用此方法会print 19,22,23,99,21,20 
linklist.displayallnodes(); 
}
}

至此，对单链表的操作就笔记到这里了。

以上所述是小编给大家介绍的java单链表的实现代码，希望对大家有所帮助