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An efficient, fast, convenient, easy to learn, easy to use MVC framework and ORM framework. It is seamless compatible with JSTL and supports FreeMarker. It can run independently, and it can also be applied to traditional Java Web projects. It is an efficient, fast, convenient, easy to learn and easy to use MVC framework and ORM framework. It is seamless compatible with JSTL and supports FreeMarker. It can be run on its own, or it can be applied to traditional Java Web projects

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package org.docshare.mvc;

import java.io.File;
import java.util.ArrayList;
import java.util.HashMap;

import org.docshare.log.Log;
import org.docshare.util.FileTool;

/**
 * 重新加载修改的class文件
 * @author Tongfeng Yang
 *
 */
public class Reloader {
	protected String root;
	protected HashMap last_tm=new HashMap();
	ArrayList reloadList = new ArrayList();
	ClassLoader loader = null;
	Class clz = null;
	protected String reloadPkg; //需要监测重新加载的包
	public Reloader(String clsRoot,String reloadPkg) {
		setParam(clsRoot,reloadPkg);
	}
	 Reloader(){
		
	}
	public void setParam(String clsRoot,String reloadPkg){
		this.root = clsRoot;
		this.reloadPkg = reloadPkg;
		
	}
	
	int loaderVersion = 0;
	
	
	/**
	 * 递归扫描目录
	 * @param reloadDir
	 */
	public void scan(String reloadDir){
		T("start scan ...");
		if(reloadDir == null){
			reloadDir = root;
		}
		reloadList.clear();
		scan(new File(reloadDir));
		if(reloadList.size()>0){
			loader = new YangClassLoader(++loaderVersion,root,reloadPkg);
		}
		for(String p: reloadList){
			String cname = path2Class(p);
			reloadCls(p, cname);
		}
	}

	private void scan(File reloadF){
		File[] childs = reloadF.listFiles();
		for(File c: childs){
			//out.println(c.getAbsolutePath());
			if(c.isFile() && c.getName().endsWith(".class")){
				checkFile(c);
			}else{
				scan(c);
			}
		}
	}
	
	/**
	 * 路径转类名
	 * @param path
	 * @return
	 */
	private String path2Class(String path){
		String t = path.replace(root, "");
		t = t.replace("/", ".").replace("\\", ".").replace(".class", "");
		if(t.startsWith(".")){
			t = t.substring(1);
		}
		return t;
		
	}
	private void checkFile(File c) {
		String path = c.getAbsolutePath();
		long now = c.lastModified();
		if(last_tm.containsKey(path)){
			long last = last_tm.get(path);
			if(now > last){
				reloadList.add(path);
				T("find a file need to reload "+path);
				last_tm.put(path, now);
			}
		}else{
			last_tm.put(path, now);
		}
	}
	public Class load(String clsName) throws ClassNotFoundException{
		if(!Config.reloadable){
			Class ret = Class.forName(clsName);
			MethodAccessCacher.putIfNoExist(clsName,ret);
		}
		//下面是打开了reloadable选项后的功能
		
		ClassLoader loader  = classIsUpdate(clsName);
		
		return Class.forName(clsName, true, loader);
	}
	

	
	/**
	 * 检查是否更新了，如果更新了。返回真，并记录这一次的文件修改时间
	 * @param clsName 类名
	 * @return 类加载器
	 */
	public ClassLoader classIsUpdate(String clsName){
		String path = clsToPath(clsName);
		if(! FileTool.exists(path) && FileTool.exists("bin/") && ! path.contains("bin/") ){
			path = "bin"+path;
		}

		File c = new File(path);
		long now = c.lastModified();
		if(last_tm.containsKey(path)){
			long last = last_tm.get(path);
			if(now > last){
				
				T("find a file need to reload "+path);
				last_tm.put(path, now);
				loader = new YangClassLoader(++loaderVersion,root,reloadPkg);
				return loader;
			}
		}else{
			last_tm.put(path, now);
			
		}
		if(loader == null){
			loader = new YangClassLoader(++loaderVersion,root,reloadPkg);
		}
		return loader;
	}
	
	protected String clsToPath(String clsName) {
		if(!root.endsWith("/"))root += "/";
		
		return root+clsName.replace(".","/") +".class";
	}

	private void reloadCls(String fileName,String clsName) {
		try {
				T("reload "+clsName +" , from "+fileName);
				clz = loader.loadClass(clsName);
				T("load succ "+ clz.hashCode());
				//Animal animal = (Animal)clz.newInstance();
				//animal.speak();
			
		} catch (ClassNotFoundException e) {
			T("person class not found");
		}catch (Exception e) {
			e.printStackTrace();
		}
	}
	protected void T(String s) {
		System.out.println(s);
	}
	
	public static void main(String[] args) throws InterruptedException {
		Reloader reload = new Reloader("bin","org");
		while(true){
			reload.scan("bin");
			Thread.sleep(1000);
		}

	}
	public static void startThread(String reloadDir){
		Thread t =new Thread(new Runnable() {
			
			@Override
			public void run() {
				Reloader reload = new Reloader("bin","org");
				while(true){
					try {
						reload.scan("bin");
						
					} catch (Exception e) {
						e.printStackTrace();
						Log.i("Reloader Thread Exception ,restart 30 second later ");
						try {
							Thread.sleep(30*1000);
						} catch (InterruptedException e1) {
							System.out.println("Reload thread interupted");
							return;
						}
					}
					try {
						Thread.sleep(1000);
					} catch (InterruptedException e) {
						System.out.println("Reload thread interupted");
						return;
					}
				}
			}
		});
		t.start();
	}
	
	@SuppressWarnings("unused")
	private static long getFileLastTm(String path){
		File f = new File(path);
		if(!f.exists()){
			return -1;
		}
		return f.lastModified();
	}
}