Accessing SWbemObject Object Properties using J-Interop Library

I am very new to J-Interop Library and WMI. I was just playing around with the following sample code from j-interop samples (MSWMI, which deals with WMI Communication).

package org.jinterop.dcom.test;

import java.net.UnknownHostException;
import java.util.logging.Level;

import org.jinterop.dcom.common.IJIUnreferenced;
import org.jinterop.dcom.common.JIException;
import org.jinterop.dcom.common.JISystem;
import org.jinterop.dcom.core.IJIComObject;
import org.jinterop.dcom.core.JIArray;
import org.jinterop.dcom.core.JICallBuilder;
import org.jinterop.dcom.core.JIComServer;
import org.jinterop.dcom.core.JIFlags;
import org.jinterop.dcom.core.JIProgId;
import org.jinterop.dcom.core.JISession;
import org.jinterop.dcom.core.JIString;
import org.jinterop.dcom.core.JIVariant;
import org.jinterop.dcom.impls.JIObjectFactory;
import org.jinterop.dcom.impls.automation.IJIDispatch;
import org.jinterop.dcom.impls.automation.IJIEnumVariant;


public class MSWMI {

private JIComServer comStub = null;
private IJIComObject comObject = null;
private IJIDispatch dispatch = null;
private String address = null;
private JISession session = null;
public MSWMI(String address, String[] args) throws JIException, UnknownHostException
{
    this.address = address;
    session = JISession.createSession(args[1],args[2],args[3]);
    session.useSessionSecurity(true);
    session.setGlobalSocketTimeout(5000);
    comStub = new JIComServer(JIProgId.valueOf("WbemScripting.SWbemLocator"),address,session);
    IJIComObject unknown = comStub.createInstance();
    comObject = (IJIComObject)unknown.queryInterface("76A6415B-CB41-11d1-8B02-00600806D9B6");//ISWbemLocator
    //This will obtain the dispatch interface
    dispatch = (IJIDispatch)JIObjectFactory.narrowObject(comObject.queryInterface(IJIDispatch.IID));
}


public void performOp() throws JIException, InterruptedException
{
    System.gc();
    JIVariant results[] = dispatch.callMethodA("ConnectServer",new Object[]{new JIString(address),JIVariant.OPTIONAL_PARAM(),JIVariant.OPTIONAL_PARAM(),JIVariant.OPTIONAL_PARAM()
            ,JIVariant.OPTIONAL_PARAM(),JIVariant.OPTIONAL_PARAM(),new Integer(0),JIVariant.OPTIONAL_PARAM()});

    //using the dispatch results above you can use the "ConnectServer" api to retrieve a pointer to IJIDispatch
    //of ISWbemServices

    //OR
    //Make a direct call like below , in this case you would get back an interface pointer to ISWbemServices , NOT to it's IDispatch
    JICallBuilder callObject = new JICallBuilder();
    callObject.addInParamAsString(address,JIFlags.FLAG_REPRESENTATION_STRING_BSTR);
    callObject.addInParamAsString("",JIFlags.FLAG_REPRESENTATION_STRING_BSTR);
    callObject.addInParamAsString("",JIFlags.FLAG_REPRESENTATION_STRING_BSTR);
    callObject.addInParamAsString("",JIFlags.FLAG_REPRESENTATION_STRING_BSTR);
    callObject.addInParamAsString("",JIFlags.FLAG_REPRESENTATION_STRING_BSTR);
    callObject.addInParamAsString("",JIFlags.FLAG_REPRESENTATION_STRING_BSTR);
    callObject.addInParamAsInt(0,JIFlags.FLAG_NULL);
    callObject.addInParamAsPointer(null,JIFlags.FLAG_NULL);
    callObject.setOpnum(0);
    callObject.addOutParamAsType(IJIComObject.class,JIFlags.FLAG_NULL);
    IJIComObject wbemServices = JIObjectFactory.narrowObject((IJIComObject)((Object[])comObject.call(callObject))[0]);
    wbemServices.setInstanceLevelSocketTimeout(1000);
    wbemServices.registerUnreferencedHandler(new IJIUnreferenced(){
        public void unReferenced()
        {
            System.out.println("wbemServices unreferenced... ");
        }
    });

    //Lets have a look at both.
    IJIDispatch wbemServices_dispatch = (IJIDispatch)JIObjectFactory.narrowObject((results[0]).getObjectAsComObject());
    results = wbemServices_dispatch.callMethodA("InstancesOf", new Object[]{new JIString("Win32_Process"), new Integer(0), JIVariant.OPTIONAL_PARAM()});
    IJIDispatch wbemObjectSet_dispatch = (IJIDispatch)JIObjectFactory.narrowObject((results[0]).getObjectAsComObject());
    JIVariant variant = wbemObjectSet_dispatch.get("_NewEnum");
    IJIComObject object2 = variant.getObjectAsComObject();

    System.out.println(object2.isDispatchSupported());
    System.out.println(object2.isDispatchSupported());

    object2.registerUnreferencedHandler(new IJIUnreferenced(){
        public void unReferenced()
        {
            System.out.println("object2 unreferenced...");
        }
    });

    IJIEnumVariant enumVARIANT = (IJIEnumVariant)JIObjectFactory.narrowObject(object2.queryInterface(IJIEnumVariant.IID));

    //This will return back a dispatch of ISWbemObjectSet

    //OR
    //It returns back the pointer to ISWbemObjectSet
    callObject = new JICallBuilder();
    callObject.addInParamAsString("Win32_Process",JIFlags.FLAG_REPRESENTATION_STRING_BSTR);
    callObject.addInParamAsInt(0,JIFlags.FLAG_NULL);
    callObject.addInParamAsPointer(null,JIFlags.FLAG_NULL);
    callObject.setOpnum(4);
    callObject.addOutParamAsType(IJIComObject.class,JIFlags.FLAG_NULL);
    IJIComObject wbemObjectSet = JIObjectFactory.narrowObject((IJIComObject)((Object[])wbemServices.call(callObject))[0]);

    //okay seen enough of the other usage, lets just stick to disptach, it's lot simpler
    JIVariant Count = wbemObjectSet_dispatch.get("Count");
    int count = Count.getObjectAsInt();
    for (int i = 0; i < count; i++)
    {
        Object[] values = enumVARIANT.next(1);
        JIArray array = (JIArray)values[0];
        Object[] arrayObj = (Object[])array.getArrayInstance();
        for (int j = 0; j < arrayObj.length; j++)
        {
            IJIDispatch wbemObject_dispatch = (IJIDispatch)JIObjectFactory.narrowObject(((JIVariant)arrayObj[j]).getObjectAsComObject());
            JIVariant variant2 = (JIVariant)(wbemObject_dispatch.callMethodA("GetObjectText_",new Object[]{new Integer(1)}))[0];
            System.out.println(variant2.getObjectAsString().getString());
            System.out.println("++++++++++++++++++++++++++++++++++++++++++++++++++++++++++");
        }
    }


}

private void killme() throws JIException
{
    JISession.destroySession(session);
}

public static void main(String[] args) {

    try {
            if (args.length < 4)
            {
                System.out.println("Please provide address domain username password");
                return;
            }

            JISystem.getLogger().setLevel(Level.INFO);
            JISystem.setInBuiltLogHandler(false);
            JISystem.setAutoRegisteration(true);
            MSWMI test = new MSWMI(args[0],args);
            for (int i = 0 ; i < 100; i++)
            {
                System.out.println("Index i: " + i);
                test.performOp();
            }
            test.killme();
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.p开发者_如何学PythonrintStackTrace();
        }
}
}

I understand that the following line of code calls the method "GetObjectText_" of the SWbemObject Object and we can see all the properties of the class instance.

JIVariant variant2 = (JIVariant)(wbemObject_dispatch.callMethodA("GetObjectText_",new Object[]{new Integer(1)}))[0];

What I wish to find out is, what should I do if I just need to retrieve a single property value, for example, if all I wanted was to retrieve the "InstallDate" property of the "Win32_Process" Class, what method would I call or how to access a particular property if I knew the property name I wish to access.

Any help on this topic would be great. Thanks a lot!!

You could access a property with the following code:

JIVariant variant2 = (JIVariant)(wbemObject_dispatch.get("Caption"));

This replaces the line:

JIVariant variant2 = (JIVariant)(wbemObject_dispatch.callMethodA("GetObjectText_",new Object[]{new Integer(1)}))[0];

The “InstallDate” properties were all empty so I use the “Caption”.