Invalid managed object reference eror

[Ghetas]

Hi everyone
I am using VirtualBox API to get the CPU usage for running Virtual machine the code gives my CPU usage but some times it throws the following exception

Code: Select all

Exception in thread "Thread-2" org.virtualbox_5_0.VBoxException: VirtualBox error: Invalid managed object reference "0cfd805b35aebcdb-0000000000000003"
	at org.virtualbox_5_0.IPerformanceCollector.queryMetricsData(IPerformanceCollector.java:337)
	at vmutilization.VmIPerformanceCollector.CollectCpuUtilization(VmIPerformanceCollector.java:75)
	at vmutilization.VmPerformanceCollectorsThread.run(VmPerformanceCollectorsThread.java:57)
Caused by: org.virtualbox_5_0.jaxws.InvalidObjectFaultMsg: VirtualBox error: Invalid managed object reference "0cfd805b35aebcdb-0000000000000003"
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
	at com.sun.xml.internal.ws.fault.SOAPFaultBuilder.createException(SOAPFaultBuilder.java:136)
	at com.sun.xml.internal.ws.client.sei.SyncMethodHandler.invoke(SyncMethodHandler.java:108)
	at com.sun.xml.internal.ws.client.sei.SyncMethodHandler.invoke(SyncMethodHandler.java:78)
	at com.sun.xml.internal.ws.client.sei.SEIStub.invoke(SEIStub.java:135)
	at com.sun.proxy.$Proxy24.iPerformanceCollectorQueryMetricsData(Unknown Source)
	at org.virtualbox_5_0.IPerformanceCollector.queryMetricsData(IPerformanceCollector.java:325)
	... 2 more

my code is

Code: Select all

package vmutilization;

import java.rmi.RemoteException;
import java.util.Arrays;
import java.util.List;

import org.virtualbox_5_0.Holder;
import org.virtualbox_5_0.IMachine;
import org.virtualbox_5_0.IPerformanceCollector;
import org.virtualbox_5_0.IUnknown;
import org.virtualbox_5_0.IVirtualBox;
import org.virtualbox_5_0.VBoxException;
import org.virtualbox_5_0.VirtualBoxManager;

import configuration.Vm;
import loadbalancer.LoadBalancerInterface;
import print.Error;
import print.Out;


public class VmIPerformanceCollector {
	Vm vm;
	IVirtualBox vbox;
	IMachine machine;
	IPerformanceCollector oCollector;
	VirtualBoxManager mgr;
	String VboxsrvUrl;

	long scale;
	double Cpuutilization;
	
	public VmIPerformanceCollector(Vm vm){
		this.vm=vm;	
	}
	@SuppressWarnings("finally")
	public boolean ConnecttoVirtualbox(){
		boolean connectsucess=false;
		mgr = VirtualBoxManager.createInstance(null);
		try{
			mgr.connect(vm.getVboxsrvUrl(), null, null);
			vbox=mgr.getVBox();
			machine=vbox.findMachine(vm.getVmName());
			oCollector = vbox.getPerformanceCollector();	
		}catch (VBoxException e){
			Error.println(e.getMessage());
			Out.println("Cannot connect, start webserver first!");
			 System.err.println(e.getMessage());
			
		}finally{
		return connectsucess;
		}
	}
	

	
	public void setup(long Period, long Count){
		 
        oCollector.setupMetrics(Arrays.asList(new String[]{"*"}),
       		 Arrays.asList(new IUnknown[]{machine}),
                Period, Count);
	}

	public void CollectCpuUtilization(double time, LoadBalancerInterface loadbalancer) throws InterruptedException{
		

        Holder<List<String>> names = new Holder<List<String>> ();
        Holder<List<IUnknown>> objects = new Holder<List<IUnknown>>() ;
        Holder<List<String>> units = new Holder<List<String>>();
        Holder<List<Long>> scales =  new Holder<List<Long>>();
        Holder<List<Long>> sequenceNumbers =  new Holder<List<Long>>();
        Holder<List<Long>> indices =  new Holder<List<Long>>();
        Holder<List<Long>> lengths =  new Holder<List<Long>>();
 
        
        List<Integer> values = oCollector.queryMetricsData(Arrays.asList(new String[]{"Guest/CPU/Load/Kernel:avg,Guest/CPU/Load/User:avg"}),
                Arrays.asList(new IUnknown[]{machine}),
                names, objects, units, scales,
                sequenceNumbers, indices, lengths);
        Cpuutilization=0;

        for (int i=0; i < names.value.size(); i++){
        		scale=scales.value.get(i);
        		
                for (int j = 0; j < lengths.value.get(i); j++)
                {
                    long val= values.get(indices.value.get(i).intValue() + j).longValue();
                    Long val2=val;
                    double val3=val2.doubleValue()/scale;
                    Cpuutilization=Cpuutilization + val3; 
                }
        }
        Cpuutilization=Math.round(Cpuutilization*100)/100.00d;
        System.out.println("Time:"+ time+" CPU Usage: "+ Cpuutilization+ " vm: "+vm.getVmName());
        vm.addStateHistoryEntry(time,Cpuutilization , 1);
        try {
			loadbalancer.UpdateVmsUsage(vm.getVmName(), Cpuutilization);
		} catch (RemoteException e) {

			e.printStackTrace();
			 System.err.println(e.getMessage());
		}
        
	}
	
	public void disconnect(){
        try {
        	oCollector.releaseRemote();
            mgr.disconnect();
        } catch (VBoxException e) {
        	e.printStackTrace();
			Error.println(e.getMessage());
			Out.println("Cannot disconnect, start webserver first!");
			 System.err.println(e.getMessage());
        }
        mgr.cleanup();
	}
	
}

I setup the authentication to be null
My Virtual Box Version is 5.14
OS: Centos 6.7
Language Java

any help will be appreciated thanks all

[noteirak]

The exception is telling you that the object you're using has lost its server counterpart - in case of performance metrics, it usually happens when the VM is powered off per example, or restarted.
The objects you are manipulating in Java are simply proxy objects which are linked to the real object on the server side, so any "managed object reference error" means that specific object is gone.

At that point, you need to ask or recreate the object throwing the exception via the API.

[Ghetas]

The exception is telling you that the object you're using has last its server counterpart - in case of performance metrics, it usually happens when the VM is powered off per example, or restarted.
The objects you are manipulating in Java are simply proxy objects which are linked to the real object on the server side, so any "managed object reference error" means that specific object is gone.

At that point, you need to ask or recreate the object throwing the exception via the API.

Thanks noteirak, this solves my problem