Java tutorial
/* * Copyright 1999-2015 dangdang.com. * <p> * 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. * </p> */ package com.dangdang.ddframe.job.internal.reg; import com.dangdang.ddframe.reg.base.CoordinatorRegistryCenter; import com.dangdang.ddframe.reg.zookeeper.ZookeeperConfiguration; import com.dangdang.ddframe.reg.zookeeper.ZookeeperRegistryCenter; import com.google.common.base.Charsets; import com.google.common.base.Optional; import com.google.common.hash.HashCode; import com.google.common.hash.Hasher; import com.google.common.hash.Hashing; import lombok.AccessLevel; import lombok.NoArgsConstructor; import java.util.concurrent.ConcurrentHashMap; /** * . * * @author zhangliang */ @NoArgsConstructor(access = AccessLevel.PRIVATE) public final class RegistryCenterFactory { private static ConcurrentHashMap<HashCode, CoordinatorRegistryCenter> registryCenterMap = new ConcurrentHashMap<>(); /** * . * * @param connectString * @param namespace ?? * @param digest ? * @return */ public static CoordinatorRegistryCenter createCoordinatorRegistryCenter(final String connectString, final String namespace, final Optional<String> digest) { Hasher hasher = Hashing.md5().newHasher().putString(connectString, Charsets.UTF_8).putString(namespace, Charsets.UTF_8); if (digest.isPresent()) { hasher.putString(digest.get(), Charsets.UTF_8); } HashCode hashCode = hasher.hash(); if (registryCenterMap.containsKey(hashCode)) { return registryCenterMap.get(hashCode); } ZookeeperConfiguration zkConfig = new ZookeeperConfiguration(connectString, namespace); if (digest.isPresent()) { zkConfig.setDigest(digest.get()); } CoordinatorRegistryCenter result = new ZookeeperRegistryCenter(zkConfig); result.init(); registryCenterMap.putIfAbsent(hashCode, result); return result; } }