JFinal 启动、请求源码简析（上篇）

1、MVC架构，设计精巧，使用简单

2、遵循COC原则，零配置，无xml

3、独创Db + Record模式，灵活便利

4、ActiveRecord支持，使数据库开发极致快速

5、自动加载修改后的java文件，开发过程中无需重启web server

6、AOP支持，拦截器配置灵活，功能强大

7、Plugin体系结构，扩展性强

8、多视图支持，支持FreeMarker、JSP、Velocity

9、强大的Validator后端校验功能

10、功能齐全，拥有struts2的绝大部分功能

11、体积小仅218K，且无第三方依赖

2、JFinal使用入门

public class CoreConfig extends JFinalConfig {

	/** 常量配置 **/
	@Override
	public void configConstant(Constants me) {
		loadPropertyFile("system_config_info.txt");
		// 设置开发模式
		me.setDevMode(getPropertyToBoolean("devMode", true));
		me.setUrlParaSeparator(Const.SYMBOLAMPERSAND);
	}

	/** 处理器配置 接管所有web请求，可在此层做功能性的拓展 **/
	@Override
	public void configHandler(Handlers me) {
		DruidStatViewHandler dvh =  new DruidStatViewHandler("/druid");
		me.add(dvh);
		
	}

	/** 拦截器配置 类似与struts2拦截器，处理action **/
	@Override
	public void configInterceptor(Interceptors me) {

		me.add(new TxByMethods("find","update","delete","save")); //声明式事物管理
		
	}

	/** 插件配置 JFinal集成了很多插件：redis,druid,quartz... **/
	@Override
	public void configPlugin(Plugins me) {

		/** 数据库监控druid **/
		DruidPlugin dp = new DruidPlugin(getProperty("jdbcUrl"),
				getProperty("user"), getProperty("password"));
		dp.addFilter(new StatFilter()); //sql监控
		dp.addFilter(new WallFilter()); //防止sql注入
		//dp.addFilter(new WebStatFilter());
		WallFilter wall = new WallFilter();
		wall.setDbType("mysql");  //mysql
		dp.addFilter(wall);
		me.add(dp);
		
		ActiveRecordPlugin arp = new ActiveRecordPlugin(dp);
		me.add(arp);
		
		//表映射关系
		arp.addMapping(BlogConst.BLOGTABLE, "id", Blog.class);
		
		/** redis缓存支持根据不同模块使用缓存，目前我创建一个关于blog的缓存块 **/
		RedisPlugin blogRedis = new RedisPlugin(BlogConst.BLOGTABLE,
				"localhost");
		me.add(blogRedis);

		/** 定时任务插件 目前配置了一个每5秒钟执行一次的定时脚本**/
		QuartzPlugin quartzPlugin =  new QuartzPlugin("job.properies");
		me.add(quartzPlugin);

	}

	/** 路由配置：1.如下配置；2.写个类如：BlogRoute继承Routes，配置，me.add(new BlogRoute());也可 **/
	/** 路径设置：1.第三个参数；2.可通过注解@ActionKey("/index")方式 **/
	@Override
	public void configRoute(Routes me) {

		me.add("/", IndexController.class, "/index");
		/** controller配置路径 **/
		me.add("/blog", BlogController.class);

	}
	
	/*插件关闭之前【方法可选择性使用】**/	
	public void beforeJFinalStop(){
		System.out.println("插件关闭"); //这里我们可以加一些业务监控代码
	};
	
	/*插件加载完后【方法可选择性使用】**/
	public void afterJFinalStart(){
		System.out.println("加载完毕"); //这里我们可以加一些业务监控代码

	};

        <filter>
		<filter-name>jfinal</filter-name>
		<filter-class>com.jfinal.core.JFinalFilter</filter-class>
		<init-param>
			<param-name>configClass</param-name>
			<param-value>com.demo.jfinal.config.CoreConfig</param-value>
		</init-param>
	</filter>

	<filter-mapping>
		<filter-name>jfinal</filter-name>
		<url-pattern>/*</url-pattern>
	</filter-mapping>

3、JFinal启动过程简析

boolean init(JFinalConfig jfinalConfig, ServletContext servletContext) {
		this.servletContext = servletContext; //获取servletContext
		this.contextPath = servletContext.getContextPath(); //获取contextPath
		
		initPathUtil(); //初始化根路径
		
		Config.configJFinal(jfinalConfig);	// start plugin and init logger factory in this method
		constants = Config.getConstants();
		
		initActionMapping();
		initHandler();
		initRender();
		initOreillyCos();
		initTokenManager();
		
		return true;
	}

static void configJFinal(JFinalConfig jfinalConfig) {
		jfinalConfig.configConstant(constants);				initLoggerFactory();
		jfinalConfig.configRoute(routes);
		jfinalConfig.configPlugin(plugins);					startPlugins();	// very important!!!
		jfinalConfig.configInterceptor(interceptors);
		jfinalConfig.configHandler(handlers);
	}
	

public Routes add(String controllerKey, Class controllerClass, String viewPath) {
		if (controllerKey == null)
			throw new IllegalArgumentException("The controllerKey can not be null");
		// if (controllerKey.indexOf(".") != -1)
			// throw new IllegalArgumentException("The controllerKey can not contain dot character: \".\"");
		controllerKey = controllerKey.trim();
		if ("".equals(controllerKey))
			throw new IllegalArgumentException("The controllerKey can not be blank");
		if (controllerClass == null)
			throw new IllegalArgumentException("The controllerClass can not be null");
		if (!controllerKey.startsWith("/"))
			controllerKey = "/" + controllerKey;
		if (map.containsKey(controllerKey))
			throw new IllegalArgumentException("The controllerKey already exists: " + controllerKey);
		
		map.put(controllerKey, controllerClass);
		
		if (viewPath == null || "".equals(viewPath.trim()))	// view path is controllerKey by default
			viewPath = controllerKey;
		
		viewPath = viewPath.trim();
		if (!viewPath.startsWith("/"))					// "/" added to prefix
			viewPath = "/" + viewPath;
		
		if (!viewPath.endsWith("/"))					// "/" added to postfix
			viewPath = viewPath + "/";
		
		if (baseViewPath != null)						// support baseViewPath
			viewPath = baseViewPath + viewPath;
		
		viewPathMap.put(controllerKey, viewPath);
		return this;
	}

map：{/=class com.demo.jfinal.controller.index.IndexController, /blog=class com.demo.jfinal.controller.blog.BlogController}

viewPathMap：{/=/index/, /blog=/blog/}

public Plugins add(IPlugin plugin) {
		if (plugin != null)
			this.pluginList.add(plugin);
		return this;
	}

	/**
	 * The same as addGlobalActionInterceptor. It is used to compatible with earlier version of jfinal
	 */
	public Interceptors add(Interceptor globalActionInterceptor) {
		if (globalActionInterceptor != null)
			this.globalActionInterceptor.add(globalActionInterceptor);
		return this;
	}

[com.jfinal.plugin.activerecord.tx.TxByMethods@1438c5fa]

public Handlers add(Handler handler) {
		if (handler != null)
			handlerList.add(handler);
		return this;
	}

[com.jfinal.plugin.druid.DruidStatViewHandler@488d4100]

private void initRender() {
		RenderFactory renderFactory = RenderFactory.me(); //单例类RenderFactory，JFinal通过该类返回数据
		renderFactory.init(constants, servletContext);
	}

public void init(Constants constants, ServletContext servletContext) {
		this.constants = constants;
		RenderFactory.servletContext = servletContext;
		
		// init Render
		Render.init(constants.getEncoding(), constants.getDevMode());
		initFreeMarkerRender(servletContext); //初始化freeMarkerRender
		initVelocityRender(servletContext); //初始化VelocityRender
		initJspRender(servletContext); //初始化 JspRender
		initFileRender(servletContext); //初始化FileRender
		
		// create mainRenderFactory
		if (mainRenderFactory == null) {
			ViewType defaultViewType = constants.getViewType();
			if (defaultViewType == ViewType.FREE_MARKER)
				mainRenderFactory = new FreeMarkerRenderFactory();
			else if (defaultViewType == ViewType.JSP)
				mainRenderFactory = new JspRenderFactory();
			else if (defaultViewType == ViewType.VELOCITY)
				mainRenderFactory = new VelocityRenderFactory();
			else
				throw new RuntimeException("View Type can not be null.");
		}
		
		// create errorRenderFactory
		if (errorRenderFactory == null) {
			errorRenderFactory = new ErrorRenderFactory();
		}
	}

private void initOreillyCos() { //初始化参数
		OreillyCos.init(constants.getUploadedFileSaveDirectory(), constants.getMaxPostSize(), constants.getEncoding());
	}

private void initTokenManager() {
		ITokenCache tokenCache = constants.getTokenCache(); //初始化token信息
		if (tokenCache != null)
			TokenManager.init(tokenCache);
	}

                handler = jfinal.getHandler();
		constants = Config.getConstants();
		encoding = constants.getEncoding();
		jfinalConfig.afterJFinalStart();
		
		String contextPath = filterConfig.getServletContext().getContextPath();
		contextPathLength = (contextPath == null || "/".equals(contextPath) ? 0 : contextPath.length());