ParameterDumpingRequestListener.java

/*
 * JBoss, Home of Professional Open Source
 * Copyright 2015, Red Hat, Inc. and/or its affiliates, and individual
 * contributors by the @authors tag. See the copyright.txt in the
 * distribution for a full listing of individual contributors.
 *
 * 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.jboss.as.quickstarts.servlet.filterlistener;

import java.util.Map;

import javax.servlet.ServletContext;
import javax.servlet.ServletRequestEvent;
import javax.servlet.ServletRequestListener;
import javax.servlet.annotation.WebListener;

/**
 * A simple request listener that dumps all the parameters of the HTTP requests.
 * <p>
 * Because Request Listeners see requests before Filters see them, this listener sees the original parameter values as sent by
 * the user rather than the modified ones passed down the filter chain by {@link VowelRemoverFilter}.
 *
 * @author Jonathan Fuerth <jfuerth@redhat.com>
 */
@WebListener
public class ParameterDumpingRequestListener implements ServletRequestListener {

    @Override
    public void requestInitialized(ServletRequestEvent sre) {
        Map<String, String[]> paramMap = sre.getServletRequest().getParameterMap();
        ServletContext servletContext = sre.getServletContext();

        // to see log messages at runtime, check the terminal window where you started JBoss EAP.
        servletContext.log("ParameterDumpingRequestListener: request has been initialized. It has " + paramMap.size()
            + " parameters:");
        for (Map.Entry<String, String[]> entry : paramMap.entrySet()) {
            for (String val : entry.getValue()) {
                servletContext.log("  " + entry.getKey() + "=" + val);
            }
        }
    }

    @Override
    public void requestDestroyed(ServletRequestEvent sre) {
        sre.getServletContext().log("ParameterDumpingRequestListener: request has been destroyed");
    }

}