java gateway监控mem使用率

1.监控内存使用率

/**
     * des get mem usage
     * @return
     */
    private double getMemUsage()
    {
        double memUsage = 0;
       
        try
        {
            logger.info("===============test============================");
            ObjectName memObjectName = new ObjectName("java.lang:type=Memory");
            MemoryUsage heapMemoryUsage = MemoryUsage.from((CompositeDataSupport) mbsc.getAttribute(memObjectName, "HeapMemoryUsage")); 
            long maxMemory = heapMemoryUsage.getMax();// 堆最大 
            long commitMemory = heapMemoryUsage.getCommitted();// 堆当前分配 
            long usedMemory = heapMemoryUsage.getUsed(); 
           
            memUsage = (double) usedMemory  / commitMemory;
           
            logger.info("=================memUsage: " + memUsage);
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
       
        return memUsage;
    }