package com.et.mvc;
import java.io.File;
import java.io.IOException;
import java.net.JarURLConnection;
import java.net.URL;
import java.net.URLDecoder;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.et.mvc.routing.RouteResult;
import com.et.mvc.routing.RouteTable;
/**
* 分发器过滤器类，在web.xml中进行配置，具有如下参数：<br/>
* <ul>
* <li>controllerBasePackage 控制器类所属包的基包</li>
* <li>viewBasePath 放置视图模板的目录</li>
* <li>plugin 插件，多个插件以“,”分开</li>
* </ul>
* @author stworthy
*/
public class DispatcherFilter implements Filter {
private FilterConfig filterConfig = null;
private Map<String,String> configParams = null;
private Dispatcher dispatcher = null;
private List<PlugIn> plugins = new ArrayList<PlugIn>();
public DispatcherFilter() {
}
private void initControllerPaths(){
List<String> paths = new ArrayList<String>();
try{
List<String> classes = new ArrayList<String>();
String packagePath = Dispatcher.getControllerBasePackage();
packagePath = packagePath.replace(".", "/");
getControllerClasses(packagePath, classes);
for(String cp: classes){
String path = cp.substring(packagePath.length());
path = path.replace("Controller.class", "");
if (!path.startsWith("/")){
path = "/" + path;
}
int pos = path.lastIndexOf("/");
String subPackage = path.substring(0, pos);
String controllerName = path.substring(pos + 1);
String controllerFirst = controllerName.substring(0, 1);
String controllerSecond = controllerName.substring(1);
path = subPackage + "/" + controllerFirst.toLowerCase() + controllerSecond;
paths.add(path);
}
}
catch(Exception ex){
ex.printStackTrace();
}
Dispatcher.setControllerPaths(paths);
}
/**
* 获取指定包路径的所有类
* @param path 包路径，如controllers/qo
* @param classes 所有类集合，每个类包括路径，如controllers/qo/ApplicationController.class
* @throws java.lang.Exception
*/
private void getControllerClasses(String path, List<String> classes) throws Exception{
Enumeration<URL> urls = getClass().getClassLoader().getResources(path);
if (!urls.hasMoreElements()){
urls = getClass().getClassLoader().getResources("/" + path);
}
while(urls.hasMoreElements()){
URL url = urls.nextElement();
String protocol = url.getProtocol();
if (protocol.equalsIgnoreCase("file") ||
protocol.equalsIgnoreCase("vfsfile")){
String filePath = URLDecoder.decode(url.getFile(), "UTF-8");
File file = new File(filePath);
File[] ff = file.listFiles();
for(File f: ff){
String name = f.getName();
if (f.isDirectory()){
getControllerClasses(path + "/" + name, classes);
}
else if (name.endsWith(".class")){
classes.add(path + "/" + name);
}
}
}
else if (protocol.equalsIgnoreCase("jar") ||
protocol.equalsIgnoreCase("zip") ||
protocol.equalsIgnoreCase("wsjar")){
JarFile jar = ((JarURLConnection)url.openConnection()).getJarFile();
Enumeration<JarEntry> entries = jar.entries();
while(entries.hasMoreElements()){
JarEntry entry = entries.nextElement();
String name = entry.getName();
if (name.startsWith("/")){
name = name.substring(1);
}
if (name.startsWith(path) && name.endsWith(".class")){
classes.add(name);
}
}
}
}
}
private void initPlugIns(){
PlugInContext context = new PlugInContext();
context.setServletContext(this.filterConfig.getServletContext());
context.setConfigParams(configParams);
try{
String plugInClasses = filterConfig.getInitParameter("plugin");
if (plugInClasses != null){
String[] classes = plugInClasses.split(",");
for(String className: classes){
className = className.trim();
if (!className.equals("")) {
PlugIn plugin = (PlugIn)Class.forName(className).newInstance();
plugin.init(context);
plugins.add(plugin);
}
}
}
}
catch(Exception ex){
ex.printStackTrace();
}
}
/**
* Init method for this filter
*
*/
public void init(FilterConfig filterConfig) {
this.filterConfig = filterConfig;
configParams = new HashMap<String,String>();
for(Enumeration<?> e = filterConfig.getInitParameterNames(); e.hasMoreElements(); ){
String name = (String)e.nextElement();
String value = filterConfig.getInitParameter(name);
configParams.put(name, value);
}
String controllerBasePackage = filterConfig.getInitParameter("controllerBasePackage");
String viewBasePath = filterConfig.getInitParameter("viewBasePath");
if (viewBasePath.endsWith("/")){
viewBasePath = viewBasePath.substring(0,viewBasePath.length()-1);
}
Dispatcher.setControllerBasePackage(controllerBasePackage);
Dispatcher.setViewBasePath(viewBasePath);
initControllerPaths();
initPlugIns();
dispatcher = new Dispatcher();
// dispatcher = new Dispatcher(filterConfig.getServletContext(), configParams);
}
protected HttpServletRequest wrapRequest(HttpServletRequest request, Map<String,String> params) throws ServletException{
String type = request.getHeader("Content-Type"); //请求类型
if (type == null || !type.startsWith("multipart/form-data")){
return new NormalRequest(request, params);
}
else{
try{
MultipartRequest mreq = new MultipartRequest(request, params);
return mreq;
}
catch(Exception ex){
throw new ServletException(ex);
}
}
}
/**
*
* @param request The servlet request we are processing
* @param response The servlet response we are creating
* @param chain The filter chain we are processing
*
* @exception IOException if an input/output error occurs
* @exception ServletException if a servlet error occurs
*/
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain)
throws IOException, ServletException {
HttpServletRequest req = (HttpServletRequest)request;
HttpServletResponse res = (HttpServletResponse)response;
// 设置默认编码为UTF-8
req.setCharacterEncoding("UTF-8");
res.setContentType("text/html;charset=UTF-8");
RequestContext requestContext = new RequestContext();
requestContext.setControllerBasePackage(Dispatcher.getControllerBasePackage());
requestContext.setControllerPaths(Dispatcher.getControllerPaths());
requestContext.setRequest(req);
RouteResult routeResult = null;
try{
routeResult = RouteTable.selectRoute(requestContext);
}
catch(Exception ex){
throw new ServletException(ex);
}
if (routeResult == null){
chain.doFilter(request, response);
}
else{
String controllerPackage = Dispatcher.getControllerBasePackage();
if (!routeResult.getSubPackageName().equals("")){
controllerPackage += "." + routeResult.getSubPackageName();
}
String controllerClassName = controllerPackage + "." + toControllerClassName(routeResult.getControllerName());
Controller controller;
try{
controller = (Controller)getController(controllerClassName);
req = wrapRequest(req, routeResult.getParams());
controller.init(this.filterConfig.getServletContext(), req, res, routeResult);
}
catch(Exception ex){
// ex.printStackTrace();
chain.doFilter(request, response);
return;
}
try{
dispatcher.service(controller);
}
catch(Exception ex){
throw new ServletException(ex);
}
}
}
protected Object getController(String controllerClassName) throws Exception{
return Class.forName(controllerClassName).newInstance();
}
/**
* Return the filter configuration object for this filter.
*/
public FilterConfig getFilterConfig() {
return (this.filterConfig);
}
/**
* Set the filter configuration object for this filter.
*
* @param filterConfig The filter configuration object
*/
public void setFilterConfig(FilterConfig filterConfig) {
this.filterConfig = filterConfig;
}
/**
* Destroy method for this filter
*
*/
public void destroy() {
for(PlugIn plugin: plugins){
plugin.destroy();
}
}
/**
* 请控制器名称转换成具体的控制器类名称，首字母变成大写，后缀加上Controller。
* @param controllerName
* @return
*/
protected String toControllerClassName(String controllerName){
if (controllerName == null){
return null;
}
String first = controllerName.substring(0,1);
String second = controllerName.substring(1);
return first.toUpperCase()+second+"Controller";
}
}