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How to declare a variable to get an output as a Sub parameter using Jacob

I am using Jacob to call VBA COM interfaces in software.
I need to call a Sub that has an output parameter, that is not of canonical type (int, String, etc.) but of some dedicated interface declared in .tlb that are brought with this software.
Here is the
Sub GetMaterialOnBody (Body iBody, Material oMaterial)
So I tried many declarations and initializations for the output parameter material in the call, I get various errors and cannot seem to find the proper way to do.
Variant material = new Variant (null, false);
Dispatch.invoke(materialManager.getDispatch(), "GetMaterialOnBody", Dispatch.Method, new Object[] {hybridBody, material}, new int[1]);
but got
com.jacob.com.ComFailException: A COM exception has been encountered:
At Invoke of: GetMaterialOnBody
Description: Type mismatch.
Then I tried to call .getDispatch() on material
Variant material = new Variant (null, false);
Dispatch.invoke(materialManager.getDispatch(), "GetMaterialOnBody", Dispatch.Method, new Object[] {hybridBody, material.getDispatch()}, new int[1]);
but got
java.lang.IllegalStateException: getDispatch() only legal on Variants of type VariantDispatch, not 0
So I tried
Variant material = new Variant (null, false);
material.putNothing();
Dispatch.invoke(materialManager.getDispatch(), "GetMaterialOnBody", Dispatch.Method, new Object[] {hybridBody, material.getDispatch()}, new int[1]);
but got
com.jacob.com.ComFailException: putObject failed
at com.jacob.com.Variant.putVariantDispatch(Native Method) ~[jacob-1.14.3.jar:na]
at com.jacob.com.Variant.putDispatch(Variant.java:1341) ~[jacob-1.14.3.jar:na]
I tried different solutions, including using Ref, etc.
I am a bit lost on how exactly we have to initialize a variant/dispatch to pass as an output parameter in a Sub.
Does anyone have any clue on how to do that? The closes resources I found were handling String/Integer and not object.
This old question might be related (but obviously no answer): https://community.oracle.com/tech/developers/discussion/1548970/jacob-out-parameters-refs-in-jni
I have open a question on the jacob github
https://github.com/freemansoft/jacob-project/issues/23
Also I emailed the owner of the project on github and he said the project was dormant for some time already. As all the code is available I will take the time to compile and debug the native (C++) side in order to debug my case. I will update that question then.

if that is output parameter, shouldn't it be 'ByRef' ?
Sub GetMaterialOnBody (Body iBody, ByRef Material oMaterial)
In your case probably GetMaterialOnBody sub is expected to fill in internals of oMaterial object, not to set reference to it? Then just create an empty Material object and pass to the sub

Calling windows UWP API's from Java with JNA

How can I call a windows UWP API from the JVM?
For example the Windows.Security.Credentials API.
When attempting to use JNA none of the native library names I have tried will link, and I can't actually find a DLL that matches the name Windows.Security.Credentials.dll as described in the documentation.
Is what I want to do even possible, how can I link to and call UWP API's?

Update: I completely missed the mark on my first answer, was thinking JNI, not JNA, which looks a bit more like C# pInvoke. The code below is roughly what you'll need, but you'll need to reconstruct the v-tables for IInspectable and IPasswordVault. You can use the activation factory instead of activating the instance through RoActivateInstance, but then you'll need to reconstruct the interface for IActivationFactory as well. Otherwise the call suquence below is correct, if in the wrong language.
You can link and call against RoActivateInstance or RoGetActivationFactory and use the low-level COM-styl ABI interfaces defined the SDK in Windows.Security.Credentials.h. Same import lib as above.
eg:
IInspectable *pI {};
Windows::Security::Credentials::IPasswordVault pPV;
HRESULT hr = RoActivateInstance(L"Windows.Security.Credentials.PasswordVault", &pI);
if (SUCCEEDED(hr)) {
hr = pI->QueryInterface(__uuidof(Windows::Security::Credentials::IPasswordVault), (void**)&pPV);
}
if (SUCCEEDED(hr)) {
IVectorView<IPasswordCredential> *pPV{}; // namespaces omitted
hr = pPV->RetrieveAll(&pPV);
}

Why does Rhino Javascript engine complain a function does not exist?

Please forgive me, as I am a Java man dabbling in Javascript business :)
I wanted to be able to define a set of integration test cases to be easy to script against a Java application. I thought Javascript would be a perfect language to script against. To that end, I am using the Rhino engine that comes with JDK 7, via Java's Scripting API. The scripts would have access to Java classes already defined in the application, and could be reused to define use case scenarios for integration testing.
In the Java application, I have binded the javascript engine itself to the script as jsengine, so that I can load javascript files (Including a JavaScript file during Rhino eval).
I have two Javascript files, as defined below:
Function.js:
function send(msg) {
send.sendMessage(msg);
}
TestCase.js
jsengine.eval(new java.io.FileReader("Function.js");
sendMsg("Test Message");
I also have the following object defined and binded to the script as "javaobj":
public class TestConnection {
...
public void send(String message) {
// Code to send the string message via JMS
}
}
However, the Rhino engine complains with the following Exception. It seems to not like calling the javaobj's send method, for some reason.
javax.script.ScriptException: sun.org.mozilla.javascript.internal.EcmaError: TypeError: Cannot find function send in object
function sendMsg(msg) {...}. (TestCase.js#3) in TestCase.js at line number 3
at com.sun.script.javascript.RhinoScriptEngine.eval(RhinoScriptEngine.java:224)
at javax.script.AbstractScriptEngine.eval(AbstractScriptEngine.java:212)
at com.foo.test.scenario.JavaScriptEngine.execute(JavaScriptEngine.java:56)
at com.foo.test.TestSuite.start(TestSuite.java:88)
at com.foo.test.TestSuite.main(TestSuite.java:41)
Caused by: sun.org.mozilla.javascript.internal.EcmaError: TypeError: Cannot find function send in object
function sendMsg(msg) {...}. (TestCase.js#3) in TestCase.js at line number 3
at sun.org.mozilla.javascript.internal.ScriptRuntime.constructError(ScriptRuntime.java:3773)
at sun.org.mozilla.javascript.internal.ScriptRuntime.constructError(ScriptRuntime.java:3751)
at sun.org.mozilla.javascript.internal.ScriptRuntime.typeError(ScriptRuntime.java:3779)
at sun.org.mozilla.javascript.internal.ScriptRuntime.typeError2(ScriptRuntime.java:3798)
at sun.org.mozilla.javascript.internal.ScriptRuntime.notFunctionError(ScriptRuntime.java:3869)
at sun.org.mozilla.javascript.internal.ScriptRuntime.getPropFunctionAndThisHelper(ScriptRuntime.java:2345)
at sun.org.mozilla.javascript.internal.ScriptRuntime.getPropFunctionAndThis(ScriptRuntime.java:2312)
at sun.org.mozilla.javascript.internal.Interpreter.interpretLoop(Interpreter.java:1524)
at sun.org.mozilla.javascript.internal.Interpreter.interpret(Interpreter.java:854)
at sun.org.mozilla.javascript.internal.InterpretedFunction.call(InterpretedFunction.java:164)
at sun.org.mozilla.javascript.internal.ContextFactory.doTopCall(ContextFactory.java:429)
at com.sun.script.javascript.RhinoScriptEngine$1.superDoTopCall(RhinoScriptEngine.java:116)
at com.sun.script.javascript.RhinoScriptEngine$1.doTopCall(RhinoScriptEngine.java:109)
at sun.org.mozilla.javascript.internal.ScriptRuntime.doTopCall(ScriptRuntime.java:3163)
at sun.org.mozilla.javascript.internal.InterpretedFunction.exec(InterpretedFunction.java:175)
at sun.org.mozilla.javascript.internal.Context.evaluateReader(Context.java:1159)
at com.sun.script.javascript.RhinoScriptEngine.eval(RhinoScriptEngine.java:214)
... 4 more
Has anyone ever encountered this type of issue with Rhino?
P.S. This question seems related, but no answer given as well (TypeError in Rhino: migration from Java 6 to Java 7)

Looks like I found my own answer. There was a name conflict between the Javascript function and the name of the binded Java object. Both having the same name, the engine tries to call a non-existent method on a Function object!
Silly me... :P

Using Inline::Java in perl with threads

I am writing a trading program in perl with the newest Finance::InteractiveBrokers::TWS
module. I kick off a command line interface in a separate thread at the
beginning of my program but then when I try to create a tws object, my program
exits with this message:
As of Inline v0.30, use of the Inline::Config module is no longer supported or
allowed. If Inline::Config exists on your system, it can be removed. See the
Inline documentation for information on how to configure Inline. (You should
find it much more straightforward than Inline::Config :-)
I have the newest versions of Inline and Inline::Java. I looked at TWS.pm and it doesn't seem to be using Inline::Config. I set 'SHARED_JVM => 1' in the 'use Inline()' and 'Inline->bind()' calls in TWS.pm but that did not resolve the issue...
My Code:
use Finance::InteractiveBrokers::TWS;
use threads;
use threads::shared;
our $callback;
our $tws;
my $interface = UserInterface->new();
share($interface);
my $t = threads->create(sub{$interface->runUI()});
$callback= TWScallback->new();
$tws = Finance::InteractiveBrokers::TWS->new($manager); #This is where the program fails

So is Inline::Config installed on your system or not? A cursory inspection of the code is not sufficient to tell whether Perl is loading a module or not. There are too many esoteric ways (some intentional and some otherwise) to load a package or otherwise populate a namespace.
The error message in question comes from this line of code in Inline.pm:
croak M14_usage_Config() if %main::Inline::Config::;
so something in your program is populating the Inline::Config namespace. You should do what the program instructs you to do: find out where Inline/Config.pm is installed on your system (somewhere in your #INC path) and delete it.

Pinning a Java application to the Windows 7 taskbar

I use Launch4j as a wrapper for my Java application under Windows 7, which, to my understanding, in essence forks an instance of javaw.exe that in turn interprets the Java code. As a result, when attempting to pin my application to the task bar, Windows instead pins javaw.exe. Without the required command line, my application will then not run.
As you can see, Windows also does not realize that Java is the host application: the application itself is described as "Java(TM) Platform SE binary".
I have tried altering the registry key HKEY_CLASSES_ROOT\Applications\javaw.exe to add the value IsHostApp. This alters the behavior by disabling pinning of my application altogether; clearly not what I want.
After reading about how Windows interprets instances of a single application (and a phenomenon discussed in this question), I became interested in embedding a Application User Model ID (AppUserModelID) into my Java application.
I believe that I can resolve this by passing a unique AppUserModelID to Windows. There is a shell32 method for this, SetCurrentProcessExplicitAppUserModelID. Following Gregory Pakosz suggestion, I implemented it in an attempt to have my application recognized as a separate instance of javaw.exe:
NativeLibrary lib;
try {
lib = NativeLibrary.getInstance("shell32");
} catch (Error e) {
Logger.out.error("Could not load Shell32 library.");
return;
}
Object[] args = { "Vendor.MyJavaApplication" };
String functionName = "SetCurrentProcessExplicitAppUserModelID";
try {
Function function = lib.getFunction(functionName);
int ret = function.invokeInt(args);
if (ret != 0) {
Logger.out.error(function.getName() + " returned error code "
+ ret + ".");
}
} catch (UnsatisfiedLinkError e) {
Logger.out.error(functionName + " was not found in "
+ lib.getFile().getName() + ".");
// Function not supported
}
This appears to have no effect, but the function returns without error. Diagnosing why is something of a mystery to me. Any suggestions?
Working implementation
The final implementation that worked is the answer to my follow-up question concerning how to pass the AppID using JNA.
I had awarded the bounty to Gregory Pakosz' brilliant answer for JNI that set me on the right track.
For reference, I believe using this technique opens the possibility of using any of the APIs discussed in this article in a Java application.

I don't have Windows 7 but here is something that might get you started:
On the Java side:
package com.stackoverflow.homework;
public class MyApplication
{
static native boolean setAppUserModelID();
static
{
System.loadLibrary("MyApplicationJNI");
setAppUserModelID();
}
}
And on the native side, in the source code of the `MyApplicationJNI.dll library:
JNIEXPORT jboolean JNICALL Java_com_stackoverflow_homework_MyApplication_setAppUserModelID(JNIEnv* env)
{
LPCWSTR id = L"com.stackoverflow.homework.MyApplication";
HRESULT hr = SetCurrentProcessExplicitAppUserModelID(id);
return hr == S_OK;
}
Your question explicitly asked for a JNI solution. However, since your application doesn't need any other native method, jna is another solution which will save you from writing native code just for the sake of forwarding to the windows api. If you decide to go jna, pay attention to the fact that SetCurrentProcessExplicitAppUserModelID() is expecting a UTF-16 string.
When it works in your sandbox, the next step is to add operating system detection in your application as SetCurrentProcessExplicitAppUserModelID() is obviously only available in Windows 7:
you may do that from the Java side by checking that System.getProperty("os.name"); returns "Windows 7".
if you build from the little JNI snippet I gave, you can enhance it by dynamically loading the shell32.dll library using LoadLibrary then getting back the SetCurrentProcessExplicitAppUserModelID function pointer using GetProcAddress. If GetProcAddress returns NULL, it means the symbol is not present in shell32 hence it's not Windows 7.
EDIT: JNA Solution.
References:
The JNI book for more JNI examples
Java Native Access (JNA)

There is a Java library providing the new Windows 7 features for Java. It's called J7Goodies by Strix Code. Applications using it can be properly pinned to the Windows 7 taskbar. You can also create your own jump lists, etc.

I have implemented access to the SetCurrentProcessExplicitAppUserModelID method using JNA and it works quite well when used as the MSDN documentation suggests. I've never used the JNA api in the way you have in your code snippet. My implementation follows the typical JNA usage instead.
First the Shell32 interface definition:
interface Shell32 extends StdCallLibrary {
int SetCurrentProcessExplicitAppUserModelID( WString appID );
}
Then using JNA to load Shell32 and call the function:
final Map<String, Object> WIN32API_OPTIONS = new HashMap<String, Object>() {
{
put(Library.OPTION_FUNCTION_MAPPER, W32APIFunctionMapper.UNICODE);
put(Library.OPTION_TYPE_MAPPER, W32APITypeMapper.UNICODE);
}
};
Shell32 shell32 = (Shell32) Native.loadLibrary("shell32", Shell32.class,
WIN32API_OPTIONS);
WString wAppId = new WString( "Vendor.MyJavaApplication" );
shell32.SetCurrentProcessExplicitAppUserModelID( wAppId );
Many of the API's in the last article you mentioned make use of Windows COM which is quite difficult to use directly with JNA. I have had some success creating a custom DLL to call these API's (eg. using the SHGetPropertyStoreForWindow to set a different app ID for a submodule window) which I then use JNA to access at runtime.

Try to use JSmooth. I use always this one. In JSmooth is there an option under Skeleton by Windowed Wrapper called
Lauch java app in exe process
See on this image.
(source: andrels.com)
Also command line arguments can be passed.
I think this can be a solution for you.
Martijn

SetCurrentProcessExplicitAppUserModelID (or SetAppID()) would in fact do what you're trying to do. However, it might be easier to modify your installer to set the AppUserModel.ID property on your shortcut - quoting from the Application User Model ID document mentioned above:
In the System.AppUserModel.ID property of the application's shortcut file. A shortcut (as an IShellLink, CLSID_ShellLink, or a .lnk file) supports properties through IPropertyStore and other property-setting mechanisms used throughout the Shell. This allows the taskbar to identify the proper shortcut to pin and ensures that windows belonging to the process are appropriately associated with that taskbar button.
Note: The System.AppUserModel.ID property should be applied to a shortcut when that shortcut is created. When using the Microsoft Windows Installer (MSI) to install the application, the MsiShortcutProperty table allows the AppUserModelID to be applied to the shortcut when it is created during installation.

The latest jna-platform library now includes JNA bindings for SetCurrentProcessExplicitAppUserModelID:
https://github.com/java-native-access/jna/pull/680

I fixed mine without any ID settings.
There is an option in Launch4J if you are using it and you say you do then...
You can change the header to JNI Gui and then wrap it around the jar with the JRE.
The good thing is that it runs .exe in the process now instead on running javaw.exe with your jar. It probably does it under the hood (not sure).
Also I have noticed also that it takes around 40-50% less CPU resource which is even better!
And the pinning works fine and all that window features are enabled.
I hope it helps to someone as I spent nearly 2 days trying to solve that issue with my undecorated javafx app.