package com.quickwebframework.bridge;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.Servlet;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import com.quickwebframework.framework.WebContext;
import com.quickwebframework.servlet.support.DefaultRootServlet;
import com.quickwebframework.stereotype.FilterSetting;
import com.quickwebframework.util.WebResourceUtils;
public class ServletFilterBridge implements javax.servlet.Filter {
private static Log log = LogFactory.getLog(ServletFilterBridge.class
.getName());
public class ArrayFilterChain implements FilterChain {
private Filter[] filters;
private int filterIndex = -1;
private int filterCount = 0;
public Filter lastFilter;
public boolean isContinueFilterChain() {
return filterIndex >= filterCount;
}
public ArrayFilterChain(Filter[] filters) {
if (filters == null)
return;
this.filters = filters;
filterCount = filters.length;
}
public void doFilter(ServletRequest arg0, ServletResponse arg1)
throws IOException, ServletException {
if (filters == null)
return;
filterIndex++;
// 如果过滤器已使用完
if (filterIndex >= filterCount)
return;
lastFilter = filters[filterIndex];
lastFilter.doFilter(arg0, arg1, this);
}
}
// 执行过滤
public void doFilter(ServletRequest arg0, ServletResponse arg1,
FilterChain filterChain) throws IOException, ServletException {
// 判断是不是Http的Servlet请求
if (!arg0.getScheme().equals("http")) {
log.warn("ServletRequest的Scheme不是http!");
return;
}
// 先执行过滤器
ArrayFilterChain arrayFilterChain = new ArrayFilterChain(
WebContext.getFilters());
arrayFilterChain.doFilter(arg0, arg1);
// 然后判断是否执行Servlet
HttpServletRequest request = (HttpServletRequest) arg0;
HttpServletResponse response = (HttpServletResponse) arg1;
// 是否应该发送给Servlet
boolean shouldPostToServlet = false;
if (arrayFilterChain.isContinueFilterChain())
shouldPostToServlet = true;
else {
Filter lastFilter = arrayFilterChain.lastFilter;
Class<?> lastFilterClass = lastFilter.getClass();
FilterSetting lastFilterSetting = lastFilterClass
.getAnnotation(FilterSetting.class);
if (lastFilterSetting != null
&& lastFilterSetting.returnToController()) {
shouldPostToServlet = true;
} else {
shouldPostToServlet = false;
log.info("过滤器链未全部执行完成，在执行完过滤器[" + arrayFilterChain.lastFilter
+ "]后断开。");
}
}
if (!shouldPostToServlet) {
return;
}
// 根据URL分发到相应的Servlet
String requestUri = request.getRequestURI();
String contextPath = request.getContextPath();
String requestUriWithoutContextPath = requestUri.substring(contextPath
.length());
if (StringUtils.isEmpty(requestUriWithoutContextPath)) {
requestUriWithoutContextPath = "/";
}
while (requestUriWithoutContextPath.contains("//")) {
requestUriWithoutContextPath = requestUriWithoutContextPath
.replace("//", "/");
}
// 保护WEB-INF中的文件
if (requestUriWithoutContextPath.startsWith("/WEB-INF/")) {
response.sendError(400, "/WEB-INF目录拒绝访问！");
return;
}
// 如果此路径有映射的Servlet，则交由此Servlet去处理
Servlet pathServlet = WebContext
.getServletByPath(requestUriWithoutContextPath);
if (pathServlet != null) {
pathServlet.service(request, response);
return;
}
// 如果是根路径
if ("/".equals(requestUriWithoutContextPath)) {
DefaultRootServlet.getInstance().service(arg0, arg1);
return;
}
String[] splitResult = StringUtils.split(requestUriWithoutContextPath,
"/");
if (splitResult.length == 0) {
response.sendError(404, "URL not found:"
+ requestUriWithoutContextPath);
return;
}
// 如果URL包含后缀名
if (splitResult[splitResult.length - 1].contains(".")) {
String fullFilePath = WebContext
.getRealPath(requestUriWithoutContextPath);
File tmpFile = new File(fullFilePath);
// 如果文件存在，则输出资源
if (tmpFile.exists()) {
WebResourceUtils.outputResource(response,
requestUriWithoutContextPath, new FileInputStream(
tmpFile));
return;
}
}
// 如果是映射到本地的文件资源
// 如果根据/切分出来的字符串段数小于3，则不合法，返回404错误
// 正确的插件的URL构成为： [插件名]/[视图类型名]/[路径]
if (splitResult.length < 3) {
response.sendError(404, "URL " + requestUriWithoutContextPath
+ " not found!");
return;
}
String pluginName = splitResult[0];
String viewTypeName = splitResult[1];
String pathName = StringUtils.join(splitResult, "/", 2,
splitResult.length);
// 设置插件名称与路径到request的属性中
request.setAttribute(WebContext.CONST_PLUGIN_NAME, pluginName);
request.setAttribute(WebContext.CONST_PATH_NAME, pathName);
// 根据typeName，找对应的类型的处理器
Servlet typeServlet = WebContext.getViewTypeServlet(viewTypeName);
if (typeServlet != null) {
typeServlet.service(arg0, arg1);
return;
}
response.sendError(404,
String.format("未找到映射到视图类型为[%s]的Servlet!", viewTypeName));
}
// 过滤器初始化
public void init(FilterConfig arg0) throws ServletException {
WebContext.setFilterConfig(arg0);
}
public void destroy() {
// 移除所有的过滤器
WebContext.unregisterAllFilter();
}
}