/* PerformanceMonitorFilter.java
*
* Copyright 2009-2012 Comcast Interactive Media, LLC.
*
* 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.fishwife.jrugged.spring;
import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import org.fishwife.jrugged.WrappedException;
import org.springframework.jmx.export.annotation.ManagedResource;
/**
* This class is a standard Servlet filter that can be configured in web.xml to wrap all
* request handling in a {@link org.fishwife.jrugged.PerformanceMonitor}. In order to get
* useful access to the statistics, however, it is most convenient to make use of Spring's
* {@link org.springframework.web.filter.DelegatingFilterProxy} in <code>web.xml</code> and
* instantiate this filter within a Spring application context. This will allow the JMX
* annotations inherited from {@link PerformanceMonitorBean} to take effect, with the result
* that you can get a high-level performance monitor wrapped around all of your application's
* request handling.
*/
@ManagedResource
public class PerformanceMonitorFilter extends PerformanceMonitorBean implements Filter {
public void doFilter(final ServletRequest req, final ServletResponse resp,
final FilterChain chain) throws IOException, ServletException {
try {
invoke(new Runnable() {
public void run() {
try {
chain.doFilter(req, resp);
} catch (IOException e) {
throw new WrappedException(e);
} catch (ServletException e) {
throw new WrappedException(e);
}
}
});
} catch (WrappedException e) {
Throwable wrapped = e.getCause();
if (wrapped instanceof IOException) {
throw (IOException)wrapped;
} else if (wrapped instanceof ServletException) {
throw (ServletException)wrapped;
} else {
throw new IllegalStateException("unknown wrapped exception", wrapped);
}
} catch (Exception e) {
throw new IllegalStateException("unknown checked exception", e);
}
}
public void init(FilterConfig config) throws ServletException { }
public void destroy() { }
}