// ========================================================================
// $Id: Invoker.java,v 1.15 2005/08/13 00:01:27 gregwilkins Exp $
// Copyright 199-2004 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ========================================================================
package net.lightbody.bmp.proxy.jetty.jetty.servlet;
import net.lightbody.bmp.proxy.jetty.log.LogFactory;
import net.lightbody.bmp.proxy.jetty.util.LogSupport;
import net.lightbody.bmp.proxy.jetty.util.URI;
import org.apache.commons.logging.Log;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.UnavailableException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;
/* ------------------------------------------------------------ */
/** Dynamic Servlet Invoker.
* This servlet invokes anonymous servlets that have not been defined
* in the web.xml or by other means. The first element of the pathInfo
* of a request passed to the envoker is treated as a servlet name for
* an existing servlet, or as a class name of a new servlet.
* This servlet is normally mapped to /servlet/*
* This servlet support the following initParams:
* <PRE>
* nonContextServlets If false, the invoker can only load
* servlets from the contexts classloader.
* This is false by default and setting this
* to true may have security implications.
*
* verbose If true, log dynamic loads
*
* * All other parameters are copied to the
* each dynamic servlet as init parameters
* </PRE>
* @version $Id: Invoker.java,v 1.15 2005/08/13 00:01:27 gregwilkins Exp $
* @author Greg Wilkins (gregw)
*/
public class Invoker extends HttpServlet
{
private static Log log = LogFactory.getLog(Invoker.class);
private ServletHandler _servletHandler;
private Map.Entry _invokerEntry;
private Map _parameters;
private boolean _nonContextServlets;
private boolean _verbose;
/* ------------------------------------------------------------ */
public void init()
{
ServletContext config=getServletContext();
_servletHandler=((ServletHandler.Context)config).getServletHandler();
Enumeration e = getInitParameterNames();
while(e.hasMoreElements())
{
String param=(String)e.nextElement();
String value=getInitParameter(param);
String lvalue=value.toLowerCase();
if ("nonContextServlets".equals(param))
{
_nonContextServlets=value.length()>0 && lvalue.startsWith("t");
}
if ("verbose".equals(param))
{
_verbose=value.length()>0 && lvalue.startsWith("t");
}
else
{
if (_parameters==null)
_parameters=new HashMap();
_parameters.put(param,value);
}
}
}
/* ------------------------------------------------------------ */
protected void service(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
// Get the requested path and info
boolean included=false;
String servlet_path=(String)request.getAttribute(Dispatcher.__INCLUDE_SERVLET_PATH);
if (servlet_path==null)
servlet_path=request.getServletPath();
else
included=true;
String path_info = (String)request.getAttribute(Dispatcher.__INCLUDE_PATH_INFO);
if (path_info==null)
path_info=request.getPathInfo();
// Get the servlet class
String servlet = path_info;
if (servlet==null || servlet.length()<=1 )
{
response.sendError(404);
return;
}
int i0=servlet.charAt(0)=='/'?1:0;
int i1=servlet.indexOf('/',i0);
servlet=i1<0?servlet.substring(i0):servlet.substring(i0,i1);
// look for a named holder
ServletHolder holder=_servletHandler.getServletHolder(servlet);
if (holder!=null)
{
// Add named servlet mapping
_servletHandler.addServletHolder(holder);
_servletHandler.mapPathToServlet(URI.addPaths(servlet_path,servlet)+"/*", holder.getName());
}
else
{
// look for a class mapping
if (servlet.endsWith(".class"))
servlet=servlet.substring(0,servlet.length()-6);
if (servlet==null || servlet.length()==0)
{
response.sendError(404);
return;
}
synchronized(_servletHandler)
{
// find the entry for the invoker
if (_invokerEntry==null)
_invokerEntry=_servletHandler.getHolderEntry(servlet_path);
// Check for existing mapping (avoid threaded race).
String path=URI.addPaths(servlet_path,servlet);
Map.Entry entry = _servletHandler.getHolderEntry(path);
if (entry!=null && entry!=_invokerEntry)
{
// Use the holder
holder=(ServletHolder)entry.getValue();
}
else
{
// Make a holder
holder=new ServletHolder(_servletHandler,servlet,servlet);
if (_parameters!=null)
holder.putAll(_parameters);
try {holder.start();}
catch (Exception e)
{
log.debug(LogSupport.EXCEPTION,e);
throw new UnavailableException(e.toString());
}
// Check it is from an allowable classloader
if (!_nonContextServlets)
{
Object s=holder.getServlet();
if (_servletHandler.getClassLoader()!=
s.getClass().getClassLoader())
{
holder.stop();
log.warn("Dynamic servlet "+s+
" not loaded from context "+
request.getContextPath());
throw new UnavailableException("Not in context");
}
}
// Add the holder for all the possible paths
if (_verbose)
log("Dynamic load '"+servlet+"' at "+path);
_servletHandler.addServletHolder(holder);
_servletHandler.mapPathToServlet(path+"/*",holder.getName());
_servletHandler.mapPathToServlet(path+".class/*",holder.getName());
}
}
}
if (holder!=null)
holder.handle(new Request(request,included,servlet,servlet_path,path_info),
response);
else
response.sendError(404);
}
/* ------------------------------------------------------------ */
class Request extends HttpServletRequestWrapper
{
String _servletPath;
String _pathInfo;
boolean _included;
/* ------------------------------------------------------------ */
Request(HttpServletRequest request,
boolean included,
String name,
String servletPath,
String pathInfo)
{
super(request);
_included=included;
_servletPath=URI.addPaths(servletPath,name);
_pathInfo=pathInfo.substring(name.length()+1);
if (_pathInfo.length()==0)
_pathInfo=null;
}
/* ------------------------------------------------------------ */
public String getServletPath()
{
if (_included)
return super.getServletPath();
return _servletPath;
}
/* ------------------------------------------------------------ */
public String getPathInfo()
{
if (_included)
return super.getPathInfo();
return _pathInfo;
}
/* ------------------------------------------------------------ */
public Object getAttribute(String name)
{
if (_included)
{
if (name.equals(Dispatcher.__INCLUDE_REQUEST_URI))
return URI.addPaths(URI.addPaths(getContextPath(),_servletPath),_pathInfo);
if (name.equals(Dispatcher.__INCLUDE_PATH_INFO))
return _pathInfo;
if (name.equals(Dispatcher.__INCLUDE_SERVLET_PATH))
return _servletPath;
}
return super.getAttribute(name);
}
}
}