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@Override
public void init(FilterConfig config) throws ServletException {
	application = config.getServletContext();
	String loadPath = Thread.currentThread().getContextClassLoader().getResource("").getPath();
	String classPath = loadPath.substring(1, loadPath.length());
	ArrayList<String> actions = XMLReader.getNodeValues(classPath + "unicorn-config.xml", "actions");
	this.initActions(actions);
	ArrayList<String> routers = XMLReader.getNodeValues(classPath + "unicorn-config.xml", "routers");
	this.initRouters(routers);
}

@Override
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
			throws IOException, ServletException {
	HttpServletRequest request = (HttpServletRequest) servletRequest;
	String path = request.getContextPath();
	String uri = request.getRequestURI();
	String relativeUri = uri.substring(path.length(), uri.length());
	this.request = request;
	this.session = request.getSession();
	this.response = (HttpServletResponse) servletResponse;
	// 用户自定义的Router优先级最高，url先通过用户定义的
	Iterator<IPathRouter> iterator = routerList.iterator();
	while(iterator.hasNext()) {
		IPathRouter router = iterator.next();
		if(router.route(relativeUri, this)) {
			return ;
		}
	}
	// 拦截不到的继续访问
	filterChain.doFilter(servletRequest, servletResponse);
}

private void initRouters(ArrayList<String> routers) {
	routerList = new ArrayList<IPathRouter>();
	for (int i = 0; i < routers.size(); i++) {
		String routerName = routers.get(i);
		try {
			Class<?> clz = Class.forName(routers.get(i));
			// 单例模式通过方法获取对象实例
			IPathRouter router = (IPathRouter) clz.newInstance();
			routerList.add(router);
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		} catch (IllegalAccessException e) {
			e.printStackTrace();
		} catch (SecurityException e) {
			e.printStackTrace();
		} catch (IllegalArgumentException e) {
			e.printStackTrace();
		} catch (InstantiationException e) {
			e.printStackTrace();
		}
	}
	// 最后把框架默认的Router加入进来
	routerList.add(new AMPPathRouter());
}