package my.view;

import java.io.IOException;

import java.io.PrintWriter;

import java.util.Calendar;

import java.util.Date;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.apache.commons.logging.Log;

import org.apache.commons.logging.LogFactory;

import org.apache.velocity.exception.MethodInvocationException;

import org.apache.velocity.exception.ResourceNotFoundException;

import org.apache.velocity.tools.view.servlet.VelocityLayoutServlet;

/**

* 自定义velocity的错误处理

* @author liudong

*/

public final class VelocityServlet extends VelocityLayoutServlet {

private final static Log LOG = LogFactory.getLog(VelocityServlet.class);

@Override

protected void error(HttpServletRequest req, HttpServletResponse res,

Exception excp) throws ServletException {

Throwable t = excp;

if(excp instanceof MethodInvocationException)

t = ((MethodInvocationException)excp).getWrappedThrowable();

try{

if(t instanceof ResourceNotFoundException){

LOG.error(t.getMessage() + "(" + req.getRequestURL().toString() + ")");

if(!res.isCommitted())

res.sendError(HttpServletResponse.SC_NOT_FOUND);

}

else{

StringBuilder log = new StringBuilder("ERROR：Unknown Velocity Error，url=");

log.append(req.getRequestURL());

if(req.getQueryString()!=null){

log.append('?');

log.append(req.getQueryString());

}

log.append('(');

log.append(new Date());

log.append(')');

LOG.error(log.toString(), t);

log = null;

req.setAttribute("javax.servlet.jsp.jspException", t);

res.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);

}

}catch(IOException e){

LOG.error("Exception occured in VelocityServlet.error", e);

throw new ServletException(e);

}catch(IllegalStateException e){

LOG.error("==============<<IllegalStateException>>==============", e.getCause());

throw new ServletException(e);

}

return;

}

@Override

protected void doRequest(HttpServletRequest req, HttpServletResponse res)

throws ServletException, IOException {

long runtime = System.currentTimeMillis();

super.doRequest(req, res);

if(req.getAttribute("close_comment")==null){

Date cur_time = Calendar.getInstance(req.getLocale()).getTime();

PrintWriter pw = res.getWriter();

pw.print("\r\n<!-- Generated by iperl.org (");

pw.print(cur_time);

pw.print(") ");

pw.print(cur_time.getTime() - runtime);

pw.print("ms -->");

}

}

}