From 49d2ca4ee7cd1273d66a97461d82e836559dae01 Mon Sep 17 00:00:00 2001
From: Harry <chenhaowei93@163.com>
Date: Mon, 3 Apr 2017 12:50:10 +0800
Subject: [PATCH] add jvm_1 of week 6

---
 .../jvm/loader/ClassFileLoader.java           |  74 +++++++++++
 .../jvm/test/ClassFileloaderTest.java         |  88 +++++++++++++
 .../coding2017/jvm/test/EmployeeV1.java       |  28 ++++
 .../coding2017/linklist/LRUPageFrame.java     | 124 ++++++++++++++++++
 .../coding2017/linklist/LRUPageFrameTest.java |  35 +++++
 .../com/coding/basic/linklist/LinkedList.java |  12 +-
 6 files changed, 356 insertions(+), 5 deletions(-)
 create mode 100644 group02/727171008/src/com/github/HarryHook/coding2017/jvm/loader/ClassFileLoader.java
 create mode 100644 group02/727171008/src/com/github/HarryHook/coding2017/jvm/test/ClassFileloaderTest.java
 create mode 100644 group02/727171008/src/com/github/HarryHook/coding2017/jvm/test/EmployeeV1.java
 create mode 100644 group02/727171008/src/com/github/HarryHook/coding2017/linklist/LRUPageFrame.java
 create mode 100644 group02/727171008/src/com/github/HarryHook/coding2017/linklist/LRUPageFrameTest.java

diff --git a/group02/727171008/src/com/github/HarryHook/coding2017/jvm/loader/ClassFileLoader.java b/group02/727171008/src/com/github/HarryHook/coding2017/jvm/loader/ClassFileLoader.java
new file mode 100644
index 0000000000..5c52c492a3
--- /dev/null
+++ b/group02/727171008/src/com/github/HarryHook/coding2017/jvm/loader/ClassFileLoader.java
@@ -0,0 +1,74 @@
+package com.github.HarryHook.coding2017.jvm.loader;
+
+
+import java.io.ByteArrayOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+
+
+
+public class ClassFileLoader {
+
+	private List<String> clzPaths = new ArrayList<String>();
+	
+	public byte[] readBinaryCode(String className)	{
+	
+	  
+	    String fileName = clzPaths.get(0) + File.separatorChar + 
+		    className.replace('.', File.separatorChar) + ".class";
+	    
+	    InputStream in = null;
+	    try {
+		in = new FileInputStream(fileName);   
+		ByteArrayOutputStream out = new ByteArrayOutputStream(1024);
+		    
+		byte[] buffer = new byte[1024];
+		int length = 0;
+		while((length = in.read(buffer)) != -1) {
+		    out.write(buffer, 0, length);
+		}
+		return out.toByteArray();
+	    } catch(IOException e) {
+		e.printStackTrace();
+	    } finally {
+		if(in != null) {
+		    try{
+			in.close();
+		    }catch(IOException e) {
+			e.printStackTrace();
+		    }
+		}
+	    }
+	    return null;
+	    
+	}
+	
+	
+	public void addClassPath(String path) {
+		
+	    this.clzPaths.add(path);
+	}
+	
+	
+	
+	public String getClassPath(){
+	    
+	    StringBuilder buffer =  new StringBuilder();
+	    
+	    for(int i=0; i<clzPaths.size(); i++) {
+		
+		buffer.append(clzPaths.get(i));
+		if(i < clzPaths.size() - 1) {
+		    buffer.append(";");
+		}
+	    }
+	    return buffer.toString();
+	}
+
+}
diff --git a/group02/727171008/src/com/github/HarryHook/coding2017/jvm/test/ClassFileloaderTest.java b/group02/727171008/src/com/github/HarryHook/coding2017/jvm/test/ClassFileloaderTest.java
new file mode 100644
index 0000000000..2a75e2d49d
--- /dev/null
+++ b/group02/727171008/src/com/github/HarryHook/coding2017/jvm/test/ClassFileloaderTest.java
@@ -0,0 +1,88 @@
+package com.github.HarryHook.coding2017.jvm.test;
+
+import org.junit.After;
+import  org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+import com.github.HarryHook.coding2017.jvm.loader.ClassFileLoader;
+
+
+public class ClassFileloaderTest {
+    
+    	static String path1 = "F:\\Coding2017\\group02\\727171008\\bin";
+	//F:\Coding2017\group02\727171008\bin\com\github\HarryHook\coding2017\jvm\test
+	static String path2 = "F:\\temp";
+	
+	@Before
+	public void setUp() throws Exception {		 
+	}
+
+	@After
+	public void tearDown() throws Exception {
+	}
+	
+	@Test
+	public void testClassPath(){		
+		
+		ClassFileLoader loader = new ClassFileLoader();
+		
+		loader.addClassPath(path1);
+		loader.addClassPath(path2);
+		
+		String clzPath = loader.getClassPath();
+		
+		Assert.assertEquals(path1+";"+path2, clzPath);
+		
+	}
+	
+	@Test
+	public void testClassFileLength() {		
+		
+		ClassFileLoader loader = new ClassFileLoader();
+		loader.addClassPath(path1);
+		
+		String className = "com.github.HarryHook.coding2017.jvm.test.EmployeeV1";
+		
+		byte[] byteCodes = loader.readBinaryCode(className);
+		// jdk_1.8.0_111
+		Assert.assertEquals(1090, byteCodes.length);
+		
+	}
+	
+	
+    @Test	
+	public void testMagicNumber() {
+	
+    		ClassFileLoader loader = new ClassFileLoader();
+		loader.addClassPath(path1);
+		String className = "com.github.HarryHook.coding2017.jvm.test.EmployeeV1";
+		byte[] byteCodes = loader.readBinaryCode(className);
+		byte[] codes = new byte[]{byteCodes[0],byteCodes[1],byteCodes[2],byteCodes[3]};
+		
+		String acctualValue = this.byteToHexString(codes);
+		
+		Assert.assertEquals("cafebabe", acctualValue);
+	}
+    
+    
+    
+    
+    
+    
+	private String byteToHexString(byte[] codes ) {
+	   
+	    	StringBuffer buffer = new StringBuffer();
+	    	for(int i=0;i<codes.length;i++) {
+			byte b = codes[i];
+			int value = b & 0xFF;
+			String strHex = Integer.toHexString(value);
+			if(strHex.length()< 2){
+				strHex = "0" + strHex;
+			}		
+			buffer.append(strHex);
+		}
+		return buffer.toString();
+	}
+
+}
diff --git a/group02/727171008/src/com/github/HarryHook/coding2017/jvm/test/EmployeeV1.java b/group02/727171008/src/com/github/HarryHook/coding2017/jvm/test/EmployeeV1.java
new file mode 100644
index 0000000000..25dcb00cd4
--- /dev/null
+++ b/group02/727171008/src/com/github/HarryHook/coding2017/jvm/test/EmployeeV1.java
@@ -0,0 +1,28 @@
+package com.github.HarryHook.coding2017.jvm.test;
+
+public class EmployeeV1 {
+	
+	
+    private String name;
+    private int age;
+    
+    public EmployeeV1(String name, int age) {
+        this.name = name;
+        this.age = age;        
+    }    
+
+    public void setName(String name) {
+        this.name = name;
+    }
+    public void setAge(int age){
+    	this.age = age;
+    }
+    public void sayHello() {        
+    	System.out.println("Hello , this is class Employee ");    	
+    }
+    public static void main(String[] args){
+    	EmployeeV1 p = new EmployeeV1("Andy",29);
+    	p.sayHello();    
+    	
+    }
+}
\ No newline at end of file
diff --git a/group02/727171008/src/com/github/HarryHook/coding2017/linklist/LRUPageFrame.java b/group02/727171008/src/com/github/HarryHook/coding2017/linklist/LRUPageFrame.java
new file mode 100644
index 0000000000..a214913c80
--- /dev/null
+++ b/group02/727171008/src/com/github/HarryHook/coding2017/linklist/LRUPageFrame.java
@@ -0,0 +1,124 @@
+package com.github.HarryHook.coding2017.linklist;
+
+/**
+ * 用双向链表实现LRU算法
+ * @author HarryHook
+ *
+ */
+public class LRUPageFrame {
+	
+    private static class Node {
+		
+	Node prev;
+	Node next;
+	int pageNum;
+
+	Node() {
+	    
+	}
+    }
+
+    private int capacity;
+    private int currentSize = 0;
+    
+    private Node first;// 链表头
+    private Node last;// 链表尾
+
+	
+    public LRUPageFrame(int capacity) {
+		
+	this.capacity = capacity;
+		
+    }
+   
+    /**
+     * 获取缓存中对象
+     * 
+     * @param pageNum
+     * @return
+     */
+
+    
+    public void access(int pageNum) {
+	
+	if(currentSize == 0) {    
+	    Node node = new Node();
+	    node.pageNum = pageNum;
+	    node.prev = node.next = null;
+	    first = last = node;  
+	    currentSize++;
+	}else {
+	    
+	    if(first.pageNum == pageNum) { 
+		return ;
+	    }
+	    
+	    if(currentSize == 1) { 
+		addToFirst(pageNum);
+	    }else {
+		
+		if(last.pageNum == pageNum) {
+		    moveLastToFirst(); 
+		    return ;
+		}
+		Node iteratorNode = first;
+		while(iteratorNode.next != null && iteratorNode.pageNum != pageNum) {
+		    iteratorNode = iteratorNode.next;
+		}
+		if(iteratorNode == last) { 
+		    addToFirst(pageNum);
+		    //若缓存已满，移除最后一个节点
+		    if(currentSize > capacity) { 
+			last = last.prev;
+			last.next = null;
+		    }
+		}else {	
+		    moveToFirst(iteratorNode);		
+		}
+	    }
+	 }	   
+    }
+    // 将节点/缓存页添加到fitrst
+    public void addToFirst(int pageNum) {
+	Node node = new Node();
+	node.pageNum = pageNum;
+	node.prev = null;
+	node.next = first;
+	first.prev = node;
+	first = node;
+	currentSize++;
+    }
+    //将last节点移动到first
+    public void moveLastToFirst() {
+	last.next = first;
+	first.prev = last;
+	first = last;
+	last = last.prev;
+	last.next = null;
+	first.prev = null;
+    }
+    //将最近使用的已有缓存页移动到first
+    public void moveToFirst(Node iteratorNode) {
+	iteratorNode.prev.next = iteratorNode.next;
+	iteratorNode.next.prev = iteratorNode.prev;
+	iteratorNode.prev = null;
+	iteratorNode.next = first;
+	first.prev = iteratorNode;
+	first = iteratorNode;
+    }
+	
+    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();
+    }
+  
+	
+}
diff --git a/group02/727171008/src/com/github/HarryHook/coding2017/linklist/LRUPageFrameTest.java b/group02/727171008/src/com/github/HarryHook/coding2017/linklist/LRUPageFrameTest.java
new file mode 100644
index 0000000000..004b99eac4
--- /dev/null
+++ b/group02/727171008/src/com/github/HarryHook/coding2017/linklist/LRUPageFrameTest.java
@@ -0,0 +1,35 @@
+package com.github.HarryHook.coding2017.linklist;
+
+import  org.junit.Assert;
+
+import org.junit.Test;
+
+
+public class LRUPageFrameTest {
+	
+	@Test
+	public void testAccess() {
+		LRUPageFrame frame = new LRUPageFrame(3);
+		frame.access(7);
+		Assert.assertEquals("7", frame.toString());
+		frame.access(0);
+		Assert.assertEquals("0,7", frame.toString());
+		frame.access(7);
+		Assert.assertEquals("7,0", frame.toString());
+		frame.access(1);
+		Assert.assertEquals("1,7,0", frame.toString());
+		frame.access(2);
+		Assert.assertEquals("2,1,7", 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());
+	}
+
+}
diff --git a/liuxin/data-structure/src/com/coding/basic/linklist/LinkedList.java b/liuxin/data-structure/src/com/coding/basic/linklist/LinkedList.java
index f4c7556a2e..9a408dc46d 100644
--- a/liuxin/data-structure/src/com/coding/basic/linklist/LinkedList.java
+++ b/liuxin/data-structure/src/com/coding/basic/linklist/LinkedList.java
@@ -6,6 +6,12 @@
 public class LinkedList implements List {
 	
 	private Node head;
+
+	private static  class Node{
+		Object data;
+		Node next;
+		
+	}
 	
 	public void add(Object o){
 		
@@ -41,11 +47,7 @@ public Iterator iterator(){
 	}
 	
 	
-	private static  class Node{
-		Object data;
-		Node next;
-		
-	}
+
 	
 	/**
 	 * 把该链表逆置