/* | |
* Copyright 1999-2011 Alibaba Group. | |
* | |
* 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 com.alibaba.dubbo.monitor.support; | |
import java.util.Collection; | |
import java.util.Collections; | |
import java.util.Map; | |
import java.util.concurrent.ConcurrentHashMap; | |
import java.util.concurrent.locks.ReentrantLock; | |
import com.alibaba.dubbo.common.Constants; | |
import com.alibaba.dubbo.common.URL; | |
import com.alibaba.dubbo.monitor.Monitor; | |
import com.alibaba.dubbo.monitor.MonitorFactory; | |
import com.alibaba.dubbo.monitor.MonitorService; | |
/** | |
* AbstractMonitorFactroy. (SPI, Singleton, ThreadSafe) | |
* | |
* @author william.liangf | |
*/ | |
public abstract class AbstractMonitorFactroy implements MonitorFactory { | |
// 注册中心获取过程锁 | |
private static final ReentrantLock LOCK = new ReentrantLock(); | |
// 注册中心集合 Map<RegistryAddress, Registry> | |
private static final Map<String, Monitor> MONITORS = new ConcurrentHashMap<String, Monitor>(); | |
public static Collection<Monitor> getMonitors() { | |
return Collections.unmodifiableCollection(MONITORS.values()); | |
} | |
public Monitor getMonitor(URL url) { | |
url = url.setPath(MonitorService.class.getName()).addParameter(Constants.INTERFACE_KEY, MonitorService.class.getName()); | |
String key = url.toServiceString(); | |
LOCK.lock(); | |
try { | |
Monitor monitor = MONITORS.get(key); | |
if (monitor != null) { | |
return monitor; | |
} | |
monitor = createMonitor(url); | |
if (monitor == null) { | |
throw new IllegalStateException("Can not create monitor " + url); | |
} | |
MONITORS.put(key, monitor); | |
return monitor; | |
} finally { | |
// 释放锁 | |
LOCK.unlock(); | |
} | |
} | |
protected abstract Monitor createMonitor(URL url); | |
} |