1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.monitoring.web.discovery;
18
19 import org.apache.commons.monitoring.gauges.Gauge;
20
21 import javax.servlet.ServletContextEvent;
22 import javax.servlet.ServletContextListener;
23
24 public class GaugeDiscoveryListener implements ServletContextListener {
25 private Gauge.LoaderHelper helper;
26
27 @Override
28 public void contextInitialized(final ServletContextEvent sce) {
29 final String prefixesStr = sce.getServletContext().getInitParameter("monitoring.discovery.packages");
30 final String[] prefixes;
31 if (prefixesStr != null) {
32 prefixes = prefixesStr.split(",");
33 } else {
34 prefixes = new String[0];
35 }
36 helper = new Gauge.LoaderHelper("true".equals(sce.getServletContext().getInitParameter("monitoring.discovery.exclude-parent")), prefixes);
37 }
38
39 @Override
40 public void contextDestroyed(final ServletContextEvent sce) {
41 helper.destroy();
42 }
43 }