Java实现双链表互相交换任意两个节点的方法示例

public class SLink {
  public SNode head;
  public SLink() {
    this.head = new SNode();
  }
  public boolean interChangeById(int id1,int id2) {
    SNode s = head;
    SNode node1 = null,node2 = null;
    int node1Count,node2Count;
    node1Count = node2Count = 0;
    if(id1 == id2) {
      return true;
    }
    /**
     * 向下遍历
     */
    while (s.next != null) {
      s = s.next;
      node1Count ++ ;
      if(s.student.stuId == id1) {
        /**
         * 记录节点1
         */
        node1 = s;
        break;
      }
    }
    s = head;
    while (s.next != null) {
      s = s.next;
      node2Count ++ ;
      if(s.student.stuId == id2) {
        /**
         * 记录节点2
         */
        node2 = s;
        break;
      }
    }
    if(node1 != null && node2 != null) {
      SNode temp = new SNode();
      /**
       * node1在后
       */
      if(node1Count > node2Count) {
        temp.next = node1.next;
        temp.prev = node1.prev;
        /**
         * 记录那个节点就先处理那个节点
         * 1、交换next
         * 2、交换prev
         * 3、设置之前节点的next（对接）
         */
        node1.next = node2.next;
        node1.prev = node2.prev;
        node2.prev.next = node1;
        if(node1.next.equals(node1)) {
          /**
           * 说明两个节点相邻
           */
          node1.next = node2;
          node2.next = temp.next;
          node2.prev = node1;
        }else {
          /**
           * 说明节点不相邻
           */
          node2.next = temp.next;
          node2.prev = temp.prev;
          temp.prev.next = node2;
        }
      }else {
        /**
         * node1在前
         */
        temp.next = node2.next;
        temp.prev = node2.prev;
        node2.next = node1.next;
        node2.prev = node1.prev;
        node1.prev.next = node2;
        if(node2.next.equals(node2)) {
          node2.next = node1;
          node1.next = temp.next;
          node1.prev = node2;
        }else {
          node1.next = temp.next;
          node1.prev = temp.prev;
          temp.prev.next = node1;
        }
      }
      return true;
    }
    return false;
  }
  public void displayStudent() {
    SNode s = head;
    while (s.next != null) {
      s = s.next;
      System.out.println(s.student);
    }
  }
}

public class SNode {
  public Student student;
  public SNode next;
  public SNode prev;
  public SNode(Student student, SNode prev,SNode next) {
    this.student = student;
    this.next = next;
    this.prev = prev;
  }
  public SNode() {
    this.student = null;
    this.next = null;
    this.prev = null;
  }
}

public class Student {
  public int stuId;
  public String name;
  public int age;
  public String className;
  public Student(int stuId, String name, int age, String className) {
    this.stuId = stuId;
    this.name = name;
    this.age = age;
    this.className = className;
  }
  public int getStuId() {
    return stuId;
  }
  public void setStuId(int stuId) {
    this.stuId = stuId;
  }
  public String getName() {
    return name;
  }
  public void setName(String name) {
    this.name = name;
  }
  public int getAge() {
    return age;
  }
  public void setAge(int age) {
    this.age = age;
  }
  public String getClassName() {
    return className;
  }
  public void setClassName(String className) {
    this.className = className;
  }
  @Override
  public String toString() {
    return "Student{" +
        "stuId=" + stuId +
        ", name='" + name + '\'' +
        ", age=" + age +
        ", className='" + className + '\'' +
        '}';
  }
}