是否可以从该JVM实例内部访问JVM的JMX服务器？或者我是否必须通过标准的套接字/端口远程接口连接？
+----------------------------------------+ Option 2: Connect | +---------------------------+ | through sockets like | | My Notification Listener |+----->----------+ a remote | | | | | monitor. | +---------------------------+ | | | + | | | Option 1: connect| | | | to the internal | | | | JMX server. I'm | | | | trying to find | | | | if this is possible. | | | | | | | | | | | A single JVM instance. | | | | | | | | +------------+-----v------+--+ | | | | | GuageMXBean|<-+<--------------+ | | +------------+ | | | | JMX MXBean Server | | | +----------------------------+ | +----------------------------------------+
上下文：我正在尝试实现一个响应JVM状态的“智能”系统,特别是内存使用,在将工作数据缓存到磁盘之间转换,并将其保存在RAM中.设置JMX监听器似乎比运行后台线程更优雅,后台线程执行以下操作：
Runtime RTime = Runtime.getRuntime();
while(!shutdown)
{
if((RTime.totalMemory / RTime.maxMemory) > upperThreshold) cachmode = CACHetodisK;
if((RTime.totalMemory / RTime.maxMemory) < lowerThreshold) cachmode = CACHetoRAM;
Sleep(1000);
}
桌面应用程序,如果它有所作为.
这是我的第一篇SO帖子,所以欢迎任何有关改进等问题的提示.
解决方法
您可以使用此代码轻松获取平台MBean Server.
ManagementFactory.getPlatformMBeanServer();
有许多有用的MBean用于收集有关JVM状态的信息.这是一个简单的例子
List<GarbageCollectorMXBean> gcBeans = ManagementFactory.getGarbageCollectorMXBeans();
// generate heap state report
String report = "";
for (GarbageCollectorMXBean gc : gcBeans) {
report += "\nGC Name : " + gc.getName();
report += "\nCollection count: " + gc.getCollectionCount();
report += "\nCollection Time : " + gc.getCollectionTime() + " milli seconds";
report += "\n";
}
List<MemoryPoolMXBean> memoryPoolMXBeans = ManagementFactory.getMemoryPoolMXBeans();
for (MemoryPoolMXBean pool : memoryPoolMXBeans) {
report += "\nMemory Pool: " + pool.getName();
MemoryUsage usage = pool.getUsage();
report += "\n Max : " + usage.getMax() / 1024000 + "MB";
report += "\n Used: " + usage.getUsed() / 1024000 + "MB";
report += "\n";
}