Java tutorial
/** * 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.mledger.offload; import java.io.IOException; import java.util.ArrayList; import java.util.List; import lombok.Data; import lombok.extern.slf4j.Slf4j; import org.apache.bookkeeper.mledger.LedgerOffloaderFactory; import org.apache.commons.lang3.tuple.Pair; import org.apache.pulsar.common.nar.NarClassLoader; @Slf4j @Data public class Offloaders implements AutoCloseable { private final List<Pair<NarClassLoader, LedgerOffloaderFactory>> offloaders = new ArrayList<>(); public LedgerOffloaderFactory getOffloaderFactory(String driverName) throws IOException { for (Pair<NarClassLoader, LedgerOffloaderFactory> factory : offloaders) { if (factory.getRight().isDriverSupported(driverName)) { return factory.getRight(); } } throw new IOException("No offloader found for driver '" + driverName + "'." + " Please make sure you dropped the offloader nar packages under `${PULSAR_HOME}/offloaders`."); } @Override public void close() throws Exception { offloaders.forEach(offloader -> { try { offloader.getLeft().close(); } catch (IOException e) { log.warn("Failed to close nar class loader for offloader '{}': {}", offloader.getRight().getClass(), e.getMessage()); } }); } }