/*
* Copyright 1999,2004 The Apache Software Foundation.
*
* 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 org.apache.catalina.core;
import java.io.IOException;
import java.security.Principal;
import java.security.PrivilegedActionException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
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.catalina.InstanceEvent;
import org.apache.catalina.security.SecurityUtil;
import org.apache.catalina.util.InstanceSupport;
import org.apache.catalina.util.StringManager;
/**
* Implementation of <code>javax.servlet.FilterChain</code> used to manage
* the execution of a set of filters for a particular request. When the
* set of defined filters has all been executed, the next call to
* <code>doFilter()</code> will execute the servlet's <code>service()</code>
* method itself.
*
* @author Craig R. McClanahan
* @version $Revision: 1.9 $ $Date: 2004/02/27 14:58:42 $
*/
final class ApplicationFilterChain implements FilterChain {
// -------------------------------------------------------------- Constants
public static final int INCREMENT = 10;
// ----------------------------------------------------------- Constructors
/**
* Construct a new chain instance with no defined filters.
*/
public ApplicationFilterChain() {
super();
}
// ----------------------------------------------------- Instance Variables
/**
* Filters.
*/
private ApplicationFilterConfig[] filters =
new ApplicationFilterConfig[0];
/**
* The int which is used to maintain the current position
* in the filter chain.
*/
private int pos = 0;
/**
* The int which gives the current number of filters in the chain.
*/
private int n = 0;
/**
* The servlet instance to be executed by this chain.
*/
private Servlet servlet = null;
/**
* The string manager for our package.
*/
private static final StringManager sm =
StringManager.getManager(Constants.Package);
/**
* The InstanceSupport instance associated with our Wrapper (used to
* send "before filter" and "after filter" events.
*/
private InstanceSupport support = null;
// ---------------------------------------------------- FilterChain Methods
/**
* Invoke the next filter in this chain, passing the specified request
* and response. If there are no more filters in this chain, invoke
* the <code>service()</code> method of the servlet itself.
*
* @param request The servlet request we are processing
* @param response The servlet response we are creating
*
* @exception IOException if an input/output error occurs
* @exception ServletException if a servlet exception occurs
*/
public void doFilter(ServletRequest request, ServletResponse response)
throws IOException, ServletException {
if( System.getSecurityManager() != null ) {
final ServletRequest req = request;
final ServletResponse res = response;
try {
java.security.AccessController.doPrivileged(
new java.security.PrivilegedExceptionAction() {
public Object run()
throws ServletException, IOException {
internalDoFilter(req,res);
return null;
}
}
);
} catch( PrivilegedActionException pe) {
Exception e = pe.getException();
if (e instanceof ServletException)
throw (ServletException) e;
else if (e instanceof IOException)
throw (IOException) e;
else if (e instanceof RuntimeException)
throw (RuntimeException) e;
else
throw new ServletException(e.getMessage(), e);
}
} else {
internalDoFilter(request,response);
}
}
private void internalDoFilter(ServletRequest request,
ServletResponse response)
throws IOException, ServletException {
// Call the next filter if there is one
if (pos < n) {
ApplicationFilterConfig filterConfig = filters[pos++];
Filter filter = null;
try {
filter = filterConfig.getFilter();
support.fireInstanceEvent(InstanceEvent.BEFORE_FILTER_EVENT,
filter, request, response);
if( System.getSecurityManager() != null ) {
final ServletRequest req = request;
final ServletResponse res = response;
Principal principal =
((HttpServletRequest) req).getUserPrincipal();
Class[] classType = new Class[]{ServletRequest.class,
ServletResponse.class,
FilterChain.class};
Object[] args = new Object[]{req, res, this};
SecurityUtil.doAsPrivilege
("doFilter", filter, classType, args);
} else {
filter.doFilter(request, response, this);
}
support.fireInstanceEvent(InstanceEvent.AFTER_FILTER_EVENT,
filter, request, response);
} catch (IOException e) {
if (filter != null)
support.fireInstanceEvent(InstanceEvent.AFTER_FILTER_EVENT,
filter, request, response, e);
throw e;
} catch (ServletException e) {
if (filter != null)
support.fireInstanceEvent(InstanceEvent.AFTER_FILTER_EVENT,
filter, request, response, e);
throw e;
} catch (RuntimeException e) {
if (filter != null)
support.fireInstanceEvent(InstanceEvent.AFTER_FILTER_EVENT,
filter, request, response, e);
throw e;
} catch (Throwable e) {
if (filter != null)
support.fireInstanceEvent(InstanceEvent.AFTER_FILTER_EVENT,
filter, request, response, e);
throw new ServletException
(sm.getString("filterChain.filter"), e);
}
return;
}
// We fell off the end of the chain -- call the servlet instance
try {
support.fireInstanceEvent(InstanceEvent.BEFORE_SERVICE_EVENT,
servlet, request, response);
if ((request instanceof HttpServletRequest) &&
(response instanceof HttpServletResponse)) {
if( System.getSecurityManager() != null ) {
final ServletRequest req = request;
final ServletResponse res = response;
Principal principal =
((HttpServletRequest) req).getUserPrincipal();
Class[] classType = new Class[]{ServletRequest.class,
ServletResponse.class};
Object[] args = new Object[]{req, res};
SecurityUtil.doAsPrivilege("service",
servlet,
classType,
args,
principal);
} else {
servlet.service((HttpServletRequest) request,
(HttpServletResponse) response);
}
} else {
servlet.service(request, response);
}
support.fireInstanceEvent(InstanceEvent.AFTER_SERVICE_EVENT,
servlet, request, response);
} catch (IOException e) {
support.fireInstanceEvent(InstanceEvent.AFTER_SERVICE_EVENT,
servlet, request, response, e);
throw e;
} catch (ServletException e) {
support.fireInstanceEvent(InstanceEvent.AFTER_SERVICE_EVENT,
servlet, request, response, e);
throw e;
} catch (RuntimeException e) {
support.fireInstanceEvent(InstanceEvent.AFTER_SERVICE_EVENT,
servlet, request, response, e);
throw e;
} catch (Throwable e) {
support.fireInstanceEvent(InstanceEvent.AFTER_SERVICE_EVENT,
servlet, request, response, e);
throw new ServletException
(sm.getString("filterChain.servlet"), e);
}
}
// -------------------------------------------------------- Package Methods
/**
* Add a filter to the set of filters that will be executed in this chain.
*
* @param filterConfig The FilterConfig for the servlet to be executed
*/
void addFilter(ApplicationFilterConfig filterConfig) {
if (n == filters.length) {
ApplicationFilterConfig[] newFilters =
new ApplicationFilterConfig[n + INCREMENT];
System.arraycopy(filters, 0, newFilters, 0, n);
filters = newFilters;
}
filters[n++] = filterConfig;
}
/**
* Release references to the filters and wrapper executed by this chain.
*/
void release() {
n = 0;
pos = 0;
servlet = null;
support = null;
}
/**
* Set the servlet that will be executed at the end of this chain.
*
* @param wrapper The Wrapper for the servlet to be executed
*/
void setServlet(Servlet servlet) {
this.servlet = servlet;
}
/**
* Set the InstanceSupport object used for event notifications
* for this filter chain.
*
* @param support The InstanceSupport object for our Wrapper
*/
void setSupport(InstanceSupport support) {
this.support = support;
}
}