第四周 作业

group22/627559964/src/com/coding/basic/BinaryTreeNode.java

@@ -1,18 +1,18 @@
 package com.coding.basic;
 
 /**
- * �Զ��������
+ * 自定义二叉树
  * 
  * @author xiongrui233
  *
  */
 public class BinaryTreeNode {
 
-	//�ڵ�ֵ
+	//节点值
 	private Object data;
-	//������
+	//左子树
 	private BinaryTreeNode left;
-	//������
+	//右子树
 	private BinaryTreeNode right;
 
 	public Object getData() {
@@ -40,7 +40,7 @@ public void setRight(BinaryTreeNode right) {
 	}
 
 	/**
-	 * ����Ԫ��
+	 * 插入元素
 	 * @param o
 	 * @return BinaryTreeNode
 	 */

group22/627559964/src/com/coding/basic/Queue.java

@@ -1,7 +1,9 @@
 package com.coding.basic;
 
+import com.coding.basic.linklist.LinkedList;
+
 /**
- * �Զ������
+ * 自定义队列
  * 
  * @author xiongrui233
  *

group22/627559964/src/com/coding/basic/ArrayList.java → group22/627559964/src/com/coding/basic/array/ArrayList.java

@@ -1,23 +1,26 @@
-package com.coding.basic;
+package com.coding.basic.array;
 
 import java.util.Arrays;
 
+import com.coding.basic.Iterator;
+import com.coding.basic.List;
+
 /**
- * �Զ���ArrayList
+ * 自定义ArrayList
  * 
  * @author xiongrui233
  *
  */
 public class ArrayList implements List {
 
-	// list����
+	// list长度
 	private int size = 0;
 
-	// list��Ԫ�ؼ���
+	// list的元素集合
 	private Object[] elementData = new Object[10];
 
 	/**
-	 * �ϲ�����
+	 * 合并数组
 	 * 
 	 * @param arrays1
 	 * @param arrays2
@@ -31,7 +34,7 @@ private Object[] concat(Object[] arrays1, Object[] arrays2) {
 	}
 
 	/**
-	 * �ָ�����
+	 * 分割数组
 	 * 
 	 * @param arrays
 	 * @param from
@@ -47,8 +50,8 @@ private Object[] subArrays(Object[] arrays, int from, int index) {
 	}
 
 	/**
-	 * ��̬����list����
-	 * ����Ϊ:newSize = oldSize * 1.5
+	 * 动态增长list长度
+	 * 策略为:newSize = oldSize * 1.5
 	 * 
 	 * @param oldSize
 	 */
@@ -57,7 +60,7 @@ private void grow(int oldSize) {
 	}
 
 	/**
-	 * ����ڲ�����Ԫ��ʱ,list�����Ƿ��㹻
+	 * 检查在插入新元素时,list长度是否足够
 	 * 
 	 * @param newSize
 	 */
@@ -69,7 +72,7 @@ private void checkSize(int newSize) {
 	}
 
 	/**
-	 * ����Ԫ��
+	 * 新增元素
 	 * 
 	 * @param Object
 	 */
@@ -79,7 +82,7 @@ public void add(Object o) {
 	}
 
 	/**
-	 * ����Ԫ��
+	 * 新增元素
 	 * 
 	 * @param index
 	 * @param Object
@@ -96,7 +99,7 @@ public void add(int index, Object o) {
 	}
 
 	/**
-	 * ��ñ��Ϊindex��Ԫ��
+	 * 获得编号为index的元素
 	 * 
 	 * @param int
 	 * @return Object
@@ -106,7 +109,7 @@ public Object get(int index) {
 	}
 
 	/**
-	 * ɾ�����Ϊindex��Ԫ��
+	 * 删除编号为index的元素
 	 * 
 	 * @param int
 	 * @return Object
@@ -122,7 +125,7 @@ public Object remove(int index) {
 	}
 
 	/**
-	 * ����list����
+	 * 返回list长度
 	 * 
 	 * @return int
 	 */
@@ -131,7 +134,7 @@ public int size() {
 	}
 
 	/**
-	 * �������
+	 * 重写迭代器
 	 *
 	 * @return IteratorImpl
 	 */

group22/627559964/src/com/coderising/array/ArrayUtil.java → group22/627559964/src/com/coding/basic/array/ArrayUtil.java

@@ -1,4 +1,4 @@
-package com.coderising.array;
+package com.coding.basic.array;
 
 import java.util.ArrayList;
 import java.util.Arrays;

group22/627559964/src/com/coding/basic/linklist/LRUPageFrame.java

@@ -0,0 +1,151 @@
+package com.coding.basic.linklist;
+
+public class LRUPageFrame {
+
+	private static class Node {
+
+		Node prev;
+		Node next;
+		int pageNum;
+
+		Node() {
+		}
+	}
+
+	private int capacity;
+
+	private int currentSize;
+	private Node first;// 链表头
+	private Node last;// 链表尾
+
+	public LRUPageFrame(int capacity) {
+		this.currentSize = 0;
+		this.capacity = capacity;
+
+	}
+
+	/**
+	 * 获取缓存中对象
+	 * 
+	 * @param key
+	 * @return
+	 */
+	public void access(int pageNum) {
+
+		Node node = find(pageNum);
+		// 在该队列中存在， 则提到队列头
+		if (node != null) {
+
+			moveExistingNodeToHead(node);
+
+		} else {
+
+			node = new Node();
+			node.pageNum = pageNum;
+
+			// 缓存容器是否已经超过大小.
+			if (currentSize >= capacity) {
+				removeLast();
+
+			}
+
+			addNewNodetoHead(node);
+
+		}
+	}
+
+	private void addNewNodetoHead(Node node) {
+
+		if (isEmpty()) {
+
+			node.prev = null;
+			node.next = null;
+			first = node;
+			last = node;
+
+		} else {
+			node.prev = null;
+			node.next = first;
+			first.prev = node;
+			first = node;
+		}
+		this.currentSize++;
+	}
+
+	private Node find(int data) {
+
+		Node node = first;
+		while (node != null) {
+			if (node.pageNum == data) {
+				return node;
+			}
+			node = node.next;
+		}
+		return null;
+
+	}
+
+	/**
+	 * 删除链表尾部节点 表示 删除最少使用的缓存对象
+	 */
+	private void removeLast() {
+		Node prev = last.prev;
+		prev.next = null;
+		last.prev = null;
+		last = prev;
+		this.currentSize--;
+	}
+
+	/**
+	 * 移动到链表头，表示这个节点是最新使用过的
+	 * 
+	 * @param node
+	 */
+	private void moveExistingNodeToHead(Node node) {
+
+		if (node == first) {
+
+			return;
+		} else if (node == last) {
+			// 当前节点是链表尾， 需要放到链表头
+			Node prevNode = node.prev;
+			prevNode.next = null;
+			last.prev = null;
+			last = prevNode;
+
+		} else {
+			// node 在链表的中间， 把node 的前后节点连接起来
+			Node prevNode = node.prev;
+			prevNode.next = node.next;
+
+			Node nextNode = node.next;
+			nextNode.prev = prevNode;
+
+		}
+
+		node.prev = null;
+		node.next = first;
+		first.prev = node;
+		first = node;
+
+	}
+
+	private boolean isEmpty() {
+		return (first == null) && (last == null);
+	}
+
+	public String toString() {
+		StringBuilder buffer = new StringBuilder();
+		Node node = first;
+		while (node != null) {
+			buffer.append(node.pageNum);
+
+			node = node.next;
+			if (node != null) {
+				buffer.append(",");
+			}
+		}
+		return buffer.toString();
+	}
+
+}

group22/627559964/src/com/coding/basic/linklist/LRUPageFrameTest

@@ -0,0 +1,35 @@
+package com.coding.basic.linklist;
+
+
+import  org.junit.Assert;
+
+import org.junit.Test;
+
+
+public class LRUPageFrameTest {
+
+	@Test
+	public void testAccess() {
+		LRUPageFrame frame = new LRUPageFrame(3);
+		frame.access(7);
+		frame.access(0);
+		frame.access(1);
+		Assert.assertEquals("1,0,7", frame.toString());
+		frame.access(2);
+		Assert.assertEquals("2,1,0", frame.toString());
+		frame.access(0);
+		Assert.assertEquals("0,2,1", frame.toString());
+		frame.access(0);
+		Assert.assertEquals("0,2,1", frame.toString());
+		frame.access(3);
+		Assert.assertEquals("3,0,2", frame.toString());
+		frame.access(0);
+		Assert.assertEquals("0,3,2", frame.toString());
+		frame.access(4);
+		Assert.assertEquals("4,0,3", frame.toString());
+		frame.access(5);
+		Assert.assertEquals("5,4,0", frame.toString());
+
+	}
+
+}

group22/627559964/src/com/coding/basic/LinkedList.java → group22/627559964/src/com/coding/basic/linklist/LinkedList.java

@@ -1,4 +1,7 @@
-package com.coding.basic;
+package com.coding.basic.linklist;
+
+import com.coding.basic.Iterator;
+import com.coding.basic.List;
 
 /**
  * 自定义LinkList