| /** |
| * |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.bookkeeper.stats; |
| |
| import java.lang.reflect.Constructor; |
| import java.lang.reflect.InvocationTargetException; |
| import org.apache.commons.configuration.Configuration; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * An umbrella class for loading stats provider. |
| */ |
| public class Stats { |
| static final Logger LOG = LoggerFactory.getLogger(Stats.class); |
| public static final String STATS_PROVIDER_CLASS = "statsProviderClass"; |
| |
| static StatsProvider prov = new NullStatsProvider(); |
| |
| public static void loadStatsProvider(Configuration conf) { |
| String className = conf.getString(STATS_PROVIDER_CLASS); |
| loadStatsProvider(className); |
| } |
| |
| public static void loadStatsProvider(String className) { |
| if (className != null) { |
| try { |
| Class cls = Class.forName(className); |
| @SuppressWarnings("unchecked") |
| Constructor<? extends StatsProvider> cons = |
| (Constructor<? extends StatsProvider>) cls.getDeclaredConstructor(); |
| prov = cons.newInstance(); |
| } catch (ClassNotFoundException cnfe) { |
| LOG.error("Couldn't find configured class(" + className + ")", cnfe); |
| } catch (NoSuchMethodException nsme) { |
| LOG.error("Couldn't find default constructor for class (" + className + ")", nsme); |
| } catch (InstantiationException ie) { |
| LOG.error("Couldn't construct class (" + className + ")", ie); |
| } catch (IllegalAccessException iae) { |
| LOG.error("Couldn't construct class (" + className + ")," |
| + " Is the constructor private?", iae); |
| } catch (InvocationTargetException ite) { |
| LOG.error("Constructor threw an exception. It should not have.", ite); |
| } |
| } |
| } |
| |
| public static StatsProvider get() { |
| return prov; |
| } |
| } |