✨ Introducing new features.put map ok

crossoverJie · crossoverJie · commit 6855d5d7b994 · 2018-04-05T01:56:55.000+08:00
diff --git a/src/main/java/com/crossoverjie/actual/LRUMap.java b/src/main/java/com/crossoverjie/actual/LRUMap.java
@@ -18,48 +18,95 @@ public class LRUMap<K, V> {
 
     private int queueSize;
 
-    private int nodeCount ;
+    private int nodeCount;
 
 
-    private Node<K,V> header ;
-    private Node<K,V> tailer ;
+    private Node<K, V> header;
+    private Node<K, V> tailer;
 
+    public LRUMap(int queueSize) {
+        this.queueSize = queueSize;
+        header = new Node<>();
+        header.next = null;
+
+        tailer = new Node<>();
+        tailer.tail = null;
+
+        //双向链表
+        header.tail = tailer;
+        tailer.next = header;
+
+
+    }
 
     public void put(K key, V value) {
         cacheMap.put(key, value);
+        addNode(key, value);
+    }
 
+    private void addNode(K key, V value) {
 
-    }
+        Node<K, V> node = new Node<>(key, value);
 
-    private void addNode(K key,V value){
         //容量满了删除最后一个
-        if (queueSize == nodeCount){
-            tailer.next.tail = null ;
-            tailer.next = null ;
-            nodeCount -- ;
+        if (queueSize == nodeCount) {
+            delTail();
 
             //写入表头
-            Node<K,V> node = new Node<>(key,value) ;
-            header.next = node ;
-        }else {
+            addHead(node);
+        } else {
+            addHead(node);
 
         }
 
 
     }
 
 
-    private class Node<K,V> {
-        private K key ;
-        private V value ;
-        Node<K,V> tail ;
-        Node<K,V> next ;
+    /**
+     * 添加头结点
+     *
+     * @param node
+     */
+    private void addHead(Node<K, V> node) {
+
+        header.next = node;
+        node.tail = header;
+        header = node;
+        nodeCount++;
+
+        if (nodeCount == 2) {
+            tailer.next.next.tail = null;
+            tailer = tailer.next.next;
+        }
+
+    }
+
+    private void delTail() {
+        cacheMap.remove(tailer.getKey());
+
+        //删除尾结点
+        tailer.next.tail = null;
+        tailer = tailer.next;
+
+        nodeCount--;
+
+    }
+
+    private class Node<K, V> {
+        private K key;
+        private V value;
+        Node<K, V> tail;
+        Node<K, V> next;
 
         public Node(K key, V value) {
             this.key = key;
             this.value = value;
         }
 
+        public Node() {
+        }
+
         public K getKey() {
             return key;
         }
@@ -77,4 +124,9 @@ public void setValue(V value) {
         }
 
     }
+
+    @Override
+    public String toString() {
+        return cacheMap.toString();
+    }
 }
diff --git a/src/test/java/com/crossoverjie/actual/LRUMapTest.java b/src/test/java/com/crossoverjie/actual/LRUMapTest.java
@@ -0,0 +1,27 @@
+package com.crossoverjie.actual;
+
+import com.alibaba.fastjson.JSON;
+import com.sun.org.apache.bcel.internal.generic.LUSHR;
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+public class LRUMapTest {
+
+    @Test
+    public void put() throws Exception {
+        LRUMap<String,Integer> lruMap = new LRUMap(3) ;
+        lruMap.put("1",1) ;
+        lruMap.put("2",2) ;
+        lruMap.put("3",3) ;
+
+        System.out.println(lruMap.toString());
+
+        lruMap.put("4",4) ;
+        System.out.println(lruMap.toString());
+
+        lruMap.put("5",5) ;
+        System.out.println(lruMap.toString());
+    }
+
+}
