package cn.org.ape;
import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.collections.IteratorUtils;
import org.apache.commons.configuration.ConfigurationException;
import org.apache.commons.configuration.PropertiesConfiguration;
import org.apache.commons.configuration.reloading.FileChangedReloadingStrategy;
import org.apache.commons.io.FileUtils;
import org.apache.commons.lang.StringUtils;
import org.objectweb.asm.ClassReader;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import cn.org.ape.asm.ClassParsing;
import cn.org.ape.context.BeanParameter;
import cn.org.ape.http.HttpRequest;
import cn.org.ape.http.HttpResponse;
import cn.org.ape.http.RequestContext;
import cn.org.ape.http.ResponseContext;
/**
* Servlet的接口 默认的URL :servlet/*<br>
* 同时也可以配置文件 如：<br >
*
* <br >
* <servlet><br >
* <servlet-name>servlet</servlet-name><br >
* <servlet-class>cn.org.ape.ApeServlet</servlet-class><br >
* <init-param><br >
* <param-name>module</param-name><br >
* <param-value>module.properties</param-value><br >
* </init-param><br >
* <!-- 是否使用 异步处理 默认是false 不使用-->
* <async-supported>true</async-supported><br >
* <multipart-config></multipart-config><br >
* </servlet><br >
* <br >
* <br >
* <servlet-mapping><br >
* <servlet-name>servlet</servlet-name><br >
* <url-pattern>/action/*</url-pattern><br >
* </servlet-mapping><br >
* <br >
* @author 陈磊
*
*/
@WebServlet(urlPatterns= "/servlet/*")
public class ApeServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
private final static Logger log= LoggerFactory.getLogger(ApeServlet.class);
/**
* 初始化,主要是完成module的内存加载<br>
* 从配置文件中读取module对于类
*/
@Override
public void init() throws ServletException {
super.init();
String module = getInitParameter("module"); //<init-param>
if (module==null)
{
module = "ape.properties"; //设置默认的配置文件
}
this._createModules(module);
}
@Override
protected void service(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
HttpRequest request=new RequestContext(req);
HttpResponse response = new ResponseContext(resp);
String module= request.getModule();//取得调用类
String action= request.getAction(); //取得调方法
BaseAction baseAction = modules.get(module); //初始调用类
if (baseAction==null)
{
//没有找到Module 返回404
response.sendError(HttpResponse.SC_NOT_FOUND);//返回404
return ;
}
//通过asm 把request的属性赋值到调用类中属性中
ClassParsing cp = new ClassParsing();
ClassLoader classloader = baseAction.getClass().getClassLoader();
if (classloader != null)
{
//取得调用类的url
URL url = classloader.getResource(StringUtils.replace(baseAction.getClass().getName(), ".", "/") + ".class");
File file = FileUtils.toFile(url);
if (file != null)
{
ClassReader cr = new ClassReader(FileUtils.openInputStream(file));
cr.accept(cp, 0);
}
}
Map<?, ?> map=cp.getMap();
baseAction.init(request, response); //初始化baseAction
BeanParameter.populate(baseAction, request,map);//初始化bean
if (StringUtils.isNotEmpty(action))
{
baseAction.run(); //执行
}
else
{
baseAction.execute(); //默认执行
}
}
/**
* 销毁
*/
@Override
public void destroy() {
// TODO Auto-generated method stub
log.debug("destroy");
super.destroy();
}
/**
* 把配置文件的内容 存放于 HashMap<String, BaseAction>
* @param module 配置文件的名称
*/
private void _createModules(String module)
{
try {
//module这个文件会自动在下面几个地方被搜寻：当前目录 、用户主目录 、classpath
PropertiesConfiguration conf = new PropertiesConfiguration(module);
//当配置文件的内容发生改变了的时候，Commons Configuration能自 动重新读取配置文件的内容。
conf.setReloadingStrategy(new FileChangedReloadingStrategy());
@SuppressWarnings("unchecked")
List<String> keys=IteratorUtils.toList(conf.getKeys());
for (String key : keys)
{
String moduleClass = conf.getString(key);
BaseAction baseAction = _retrieveModule(moduleClass);
modules.put(key, baseAction);
}
} catch (ConfigurationException e) {
log.error("找不到配置文件 : {}\n"+e, module);
}
}
/**
* 通过类的名称 ，返回名称对于的对象。如果没有找到该对象，返回NULL
* @param moduleClass 类的名称 如：test.action.TestAction
* @return 返回 Object对象
*/
private BaseAction _retrieveModule(String moduleClass)
{
try {
BaseAction baseAction = (BaseAction) Class.forName(moduleClass).newInstance();
return baseAction;
} catch (InstantiationException e){
log.error("不存在 ：{} 类\n"+e,moduleClass);
return null;
}
catch (IllegalAccessException e){
log.error("不存在 ：{} 类\n"+e,moduleClass);
return null;
}
catch (ClassNotFoundException e) {
log.error("不存在 ：{} 类\n"+e,moduleClass);
return null;
}
}
private final static HashMap<String, BaseAction> modules = new HashMap<String, BaseAction>();
}