手寫單鏈表LinkedList,以及實現了LRU算法的單鏈表

LinkedList

public class LinkedList<T> {
        //記錄頭部節點
        public Node list;
        //記錄鏈表大小
        public int size;
        //添加節點放在頭部
        public void put(T data) {
            Node headNode = list;
            Node currentNode = new Node(data, headNode);
            list = currentNode;
            size++;
        }
        //根據指定位置添加
        public void put(int index, T data) {
            //判斷下標是否越界
            testingIndex(index);
            //這是頭部節點
            Node headNode = list;
            Node currentNode = list;
            for (int i = 0; i < index; i++) {
                headNode = currentNode;
                currentNode = currentNode.next;
            }
            Node node = new Node(data, currentNode);
            headNode.next = node;
            size++;
        }
        //刪除頭部節點
        public T remove() {
            if (list != null) {
                Node node = list;
                list = list.next;
                node.next = null;
                size--;
                return list.data;
            }
            return null;
        }
        //根據下標刪除節點
        public T remove(int index) {
            testingIndex(index);
            Node headNode = list;
            Node currentNode = list;
            for (int i = 0; i < index; i++) {
                headNode = currentNode;
                currentNode = currentNode.next;
            }
            headNode.next = currentNode.next;
            currentNode.next = null;
            size--;
            return currentNode.data;
        }
        //刪除尾部節點
        public T removeLast() {
            if (list != null) {
                Node headNode = list;
                Node currentNode = list;
                while (currentNode.next != null) {
                    headNode = currentNode;
                    currentNode = currentNode.next;
                }
                headNode.next = null;
                size--;
                return currentNode.data;
            }
            return null;
        }
        //修改節點
        public void set(int index, T data) {
            testingIndex(index);
            Node currentNode = list;
            for (int i = 0; i < index; i++) {
                currentNode = currentNode.next;
            }
            currentNode.data = data;
        }
        //查詢節點
        public T get(int index) {
            Node headNode = list;
            for (int i = 0; i < index; i++) {
                headNode = list.next;
            }
            return headNode.data;
        }
        public void testingIndex(int index) {
            if (!(index >= 0 && index <= size)) {
                throw new IndexOutOfBoundsException("index:" + index + "size:" + size);
            }
        }
        public void toStirng() {
            for (int i = 0; i < size; i++) {
                System.out.println(list.data);
                list = list.next;
            }
        }
        //節點類
        class Node {
            private T data;
            private Node next;
            public Node(T data, Node next) {
                this.data = data;
                this.next = next;
            }
        }
    }

什麼是LRU算法

代碼裏有註釋

 public class LruLinkedList<T> extends LinkedList<T> {
        /**
         * lru算法
         * 新增的數據放在頭部，添加的時候超過了內存大小，就刪除尾部
         * 緩存命中，即緩存數據被訪問時移至頭部，
         */
        public static final int defaultSize = 5;
        public int lruSize;

        public LruLinkedList() {
            this(defaultSize);
        }
        public LruLinkedList(int size) {
            this.lruSize = size;
        }
        //增
        public void lruPut(T data) {
            if (size >= lruSize) {
                removeLast();
                put(data);
            } else {
                put(data);
            }
        }
        //刪
        public void lruRemove() {
            removeLast();
        }
        //改
        public void lruSet(int index, T data) {
            testingIndex(index);
            Node head = list;
            Node cur = list;
            for (int i = 0; i < index; i++) {
                head = cur;
                cur = cur.next;
            }
            head.next = cur.next;
            cur.next=list;
            cur.data=data;
            list=cur;
        }
        //查
        public void lruGet(int index) {
            testingIndex(index);
            Node head = list;
            Node cur = list;
            for (int i = 0; i < index; i++) {
                head = cur;
                cur = cur.next;
            }
            head.next = cur.next;
            cur.next=list;
            list=cur;
        }
    }

學習算法與數據結構中，作爲學習筆記記錄
，測試問題不大，希望有大神指點，謝謝