JVM第一周作业

group10/904627477/src/com/coding/basic/LRUPageFrame.java

@@ -0,0 +1,135 @@
+package com.coding.basic;
+
+/**
+ * 用双向链表实现LRU算法
+ * @author liuxin
+ *
+ */
+public class LRUPageFrame {
+
+	private static class Node {
+
+		Node prev;
+		Node next;
+		int pageNum;
+
+		Node() {
+		}
+	}
+
+	private int capacity;
+
+
+	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 key
+	 * @return
+	 */
+	public void access(int pageNum) {		
+		Node node = findPageNumNode(pageNum);
+		if(node==null){
+			if(size()>=capacity){
+				removeLast();
+			}
+			push(pageNum);
+		}else{
+			moveToFirst(node);
+		}
+	}
+
+	public Node findPageNumNode(int pageNum) {
+		Node node = first;
+		while(node!=null){
+			if(node.pageNum==pageNum){
+				break;
+			}else{
+				node = node.next;
+			}
+		}
+		return node;
+	}
+
+	public void moveToFirst(Node node) {
+		if(first==null||node==null||first.pageNum==node.pageNum){
+			return;
+		}
+		if(node.pageNum == last.pageNum){
+			node.prev.next = null;
+			last = node.prev;
+		}else{
+			Node tPrev = node.prev;
+			Node tNext = node.next;
+			tPrev.next = tNext;
+			tNext.prev = tPrev;
+		}
+		node.prev = null;
+		node.next = first;
+		first = node;
+	}
+
+	public void push(int pageNum) {
+		if(size()==0){
+			first = new Node();
+			first.pageNum = pageNum;
+			last = first;
+			return ;
+		}
+		Node node;
+		node = new Node();
+		node.pageNum = pageNum;
+		node.next = first;
+		first.prev = node;
+		first = node;
+	}
+
+	public void removeLast() {
+		if(last==null){
+			return ;
+		}
+		if(size()==1){
+			first = null;
+			last = null;
+			return ;
+		}
+		Node temp = last.prev;
+		last.prev = null;
+		last = temp;
+		last.next = null;
+	}
+
+	public int size() {
+		int size = 0;
+		Node temp = first;
+		while (temp!=null) {
+			size++;
+			temp = temp.next;
+		}
+		return size;
+	}
+
+	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();
+	}
+
+}

group10/904627477/src/com/coding/download/FileDownloader.java

@@ -1,18 +1,12 @@
 package com.coding.download;
 
 import java.io.File;
-import java.io.FileNotFoundException;
-import java.io.IOException;
-import java.io.RandomAccessFile;
-import java.util.ArrayList;
-import java.util.List;
 import java.util.concurrent.CyclicBarrier;
 
 import com.coding.download.api.Connection;
 import com.coding.download.api.ConnectionException;
 import com.coding.download.api.ConnectionManager;
 import com.coding.download.api.DownloadListener;
-import com.coding.download.api.Resource;
 import com.coding.util.IOUtils;
 
 

group10/904627477/src/com/coding/test/ClassFileloaderTest.java

@@ -0,0 +1,88 @@
+package com.coding.test;
+
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+import com.conding.jvm.loader.ClassFileLoader;
+
+public class ClassFileloaderTest {
+
+
+	static String path1 = "D:\\workspace\\MyGithub\\coding2017\\group10\\904627477\\target\\classes";
+	static String path2 = "C:\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.coding.test.EmployeeV1";
+
+		byte[] byteCodes = loader.readBinaryCode(className);
+
+		// 注意：这个字节数可能和你的JVM版本有关系， 你可以看看编译好的类到底有多大
+		Assert.assertEquals(1040, byteCodes.length);
+
+	}
+
+
+    @Test	
+	public void testMagicNumber(){
+    	ClassFileLoader loader = new ClassFileLoader();
+		loader.addClassPath(path1);
+		String className = "com.coding.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();
+	}
+
+}

group10/904627477/src/com/coding/test/EmployeeV1.java

@@ -0,0 +1,29 @@
+package com.coding.test;
+@SuppressWarnings("unused")
+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();    
+
+    }
+}

group10/904627477/src/com/coding/test/LRUPageFrameTest.java

@@ -0,0 +1,32 @@
+package com.coding.test;
+
+import  org.junit.Assert;
+import org.junit.Test;
+
+import com.coding.basic.LRUPageFrame;
+
+
+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());
+	}
+
+}

group10/904627477/src/com/coding/util/IOUtils.java

@@ -1,12 +1,16 @@
 package com.coding.util;
 
+import java.io.ByteArrayOutputStream;
 import java.io.File;
+import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.RandomAccessFile;
 
 public class IOUtils {
 
+	private final static int DEFAULT_SIZE = 1024;
+
 	public static void writeFile(File file,int startPos,byte[] buff) throws IOException{
 		if(buff==null){
 			return;
@@ -37,4 +41,30 @@ public static void createFile(long length,String filePath){
 		}
 	}
 
+	public static byte[] readFile(String filePath) {
+		ByteArrayOutputStream out = new ByteArrayOutputStream();
+		FileInputStream in = null;
+		try {
+			in = new FileInputStream(filePath);
+			byte[] buff = new byte[DEFAULT_SIZE];
+			int len = 0;
+			while((len=in.read(buff))!=-1){
+				out.write(buff, 0, len);
+			}
+		} catch (FileNotFoundException e) {
+			e.printStackTrace();
+		} catch (IOException e) {
+			e.printStackTrace();
+		}finally{
+			if(in!=null){
+				try {
+					in.close();
+				} catch (IOException e) {
+					e.printStackTrace();
+				}
+			}
+		}
+		return out.toByteArray();
+	}
+
 }