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QueryInterface returns wrong interface in JACOB 1.17

I am trying to use JACOB 1.17 (latest stable version) to access a 64-bit in-process COM server, i.e. MyObject-x64.dll .
My CoClass has two dualinterfaces: IFoo (default), and IBar. IFoo contains foo_method(), and IBar contains bar_method(). Both methods have dispatch ID of 1.
My Java code is:
import com.jacob.activeX.ActiveXComponent;
import com.jacob.com.Dispatch;
import com.jacob.com.LibraryLoader;
import com.jacob.com.Variant;
// ...
ActiveXComponent my_object = new ActiveXComponent("MyObject.MyClass"); // OK
Dispatch.call(my_object, "foo_method"); // OK
Dispatch ibar = my_object.QueryInterface("{DE3FF217-120B-4F1E-BEF5-098B8ABDEC1F}"); // OK
Dispatch.call(ibar, "bar_method"); // Exception - "Can't map names to dispid:bar_method"
Dispatch.getIDOfName(ibar, "bar_method"); // Exception - "Can't map names to dispid:bar_method"
Dispatch.call(ibar, "foo_method"); // OK, executes foo_method
Dispatch.call(ibar, 1); // OK, executes foo_method
So, it seems that either the QueryInterface has returned the wrong interface, or the call function on ibar is calling the default interface instead of the result of the QueryInterface.
I have had a quick look through the JNI source code for jacob-1.17-x64.dll and can't see any obvious problem with the QueryInterface implementation or with the call implementation, although I haven't looked at JNI code before so I may be missing something obvious.
There is a sample that comes with JACOB, samples/com/jacob/samples/atl which accesses multiple interfaces, and it uses QueryInterface the same as I have. However I can't run this sample as it requires a MultiFace.dll which is not provided. (Source is provided but it is MSVC++-specific source, and I don't use MSVC++).
The IID in QueryInterface is definitely correct , and my object definitely isn't broken; I can access IBar fine using a free trial of one of the commercial Java-COM bridges, as well as from Visual Basic.
Is JACOB bugged or am I doing something wrong?
Using JRE 1.7.0_51-b13 .

Actually, Jacob is OK. The problem is that C++Builder XE5 has bugged implementation of IDispatch. If you QueryInterface for IDispatch plus the IID of the interface you want, then you get a valid pointer, however it actually points to the original interface you queried from, not the new one.
The other access methods all must be using vtable binding, so they did not encounter a problem.
Leaving this answer here in case anyone else has the same issue and searches.
So far, I have not discovered a workaround.

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

Why is my Com4J interface hanging during iteration?

I have to interface a third party COM API into an Java application. So I decided to use Com4j, and so far I've been satisfied, but now I've run into a problem.
After running the tlbgen I have an object called IAddressCollection which according to the original API documentation conforms to the IEnum interface definition. The object provides an iterator() function that returns a java.util.Iterator<Com4jObject>. The object comes from another object called IMessage when I want to find all the addresses for the message. So I would expect the code to work like this:
IAddressCollection adrCol = IMessage.getAddressees();
Iterator<Com4jObject> adrItr = adrCol.iterator();
while(adrItr.hasNext()){
Com4jObject adrC4j = adrItr.next();
// normally here I would handle the queryInterface
// and work with the rest of the API
}
My problem is that when I attempt the adrItr.next() nothing happens, the code stops working but hangs. No exception is thrown and I usually have to kill it through the task manager. So I'm wondering is this a problem that is common with Com4j, or am I handling this wrong, or is it possibly a problem with the API?

Ok, I hate answering my own question but in this case I found the problem. The issue was the underlying API. The IAddressCollection uses a 1 based indexing instead of a 0 based as I would have expected. It didn't provide this information in the API documentation. There is an item function where I can pull the object this way and so I can handle this with
IAddressCollection adrCol = IMessage.getAddressees();
for(int i = 1; i <= adrCol.count(); i++){
IAddress adr = adrCol.item(i);
// IAddress is the actual interface that I wanted and this works
}
So sorry for the annoyance on this.

Problems Calling a Java Class from JRuby

I'm trying to use boilerpipe from JRuby. I've seen the guide for calling Java from JRuby, and have used it successfully with another Java package, but can't figure out why the same thing isn't working with boilerpipe.
I'm trying to basically do the equivalent of this Java from JRuby:
URL url = new URL("http://www.example.com/some-location/index.html");
String text = ArticleExtractor.INSTANCE.getText(url);
Tried this in JRuby:
require 'java'
url = java.net.URL.new("http://www.example.com/some-location/index.html")
text = Java::DeL3sBoilerpipeExtractors::ArticleExtractor.INSTANCE.getText(url)
This is based on the API Javadocs for boilerpipe. Here's the error:
jruby-1.6.0 :042 > Java::DeL3sBoilerpipeExtractors::ArticleExtractor
NameError: cannot load Java class deL3sBoilerpipeExtractors.ArticleExtractor
from org/jruby/javasupport/JavaClass.java:1195:in `for_name'
from org/jruby/javasupport/JavaUtilities.java:34:in `get_proxy_class'
from /usr/local/rvm/rubies/jruby-1.6.0/lib/ruby/site_ruby/shared/builtin/javasupport/java.rb:45:in `const_missing'
from (irb):42:in `evaluate'
from org/jruby/RubyKernel.java:1087:in `eval'
from /usr/local/rvm/rubies/jruby-1.6.0/lib/ruby/1.8/irb.rb:158:in `eval_input'
from /usr/local/rvm/rubies/jruby-1.6.0/lib/ruby/1.8/irb.rb:271:in `signal_status'
from /usr/local/rvm/rubies/jruby-1.6.0/lib/ruby/1.8/irb.rb:270:in `signal_status'
from /usr/local/rvm/rubies/jruby-1.6.0/lib/ruby/1.8/irb.rb:155:in `eval_input'
from org/jruby/RubyKernel.java:1417:in `loop'
from org/jruby/RubyKernel.java:1190:in `catch'
from /usr/local/rvm/rubies/jruby-1.6.0/lib/ruby/1.8/irb.rb:154:in `eval_input'
from /usr/local/rvm/rubies/jruby-1.6.0/lib/ruby/1.8/irb.rb:71:in `start'
from org/jruby/RubyKernel.java:1190:in `catch'
from /usr/local/rvm/rubies/jruby-1.6.0/lib/ruby/1.8/irb.rb:70:in `start'
from /usr/local/rvm/rubies/jruby-1.6.0/bin/irb:17:in `(root)'
Looks like it didn't parse the camelcase into the appropriate Java package name. What am I doing wrong? I believe I've set up my classpath alright (last 3 entries), though there may be some conflict with xerces possibly being included twice:
$ echo $CLASSPATH
:/jellly/Maui1.2:/jellly/Maui1.2/src:/jellly/Maui1.2/bin:/jellly/Maui1.2/lib/commons-io-1.4.jar:/jellly/Maui1.2/lib/commons-logging.jar:/jellly/Maui1.2/lib/icu4j_3_4.jar:/jellly/Maui1.2/lib/iri.jar:/jellly/Maui1.2/lib/jena.jar:/jellly/Maui1.2/lib/maxent-2.4.0.jar:/jellly/Maui1.2/lib/mysql-connector-java-3.1.13-bin.jar:/jellly/Maui1.2/lib/opennlp-tools-1.3.0.jar:/jellly/Maui1.2/lib/snowball.jar:/jellly/Maui1.2/lib/trove.jar:/jellly/Maui1.2/lib/weka.jar:/jellly/Maui1.2/lib/wikipediaminer1.1.jar:/jellly/Maui1.2/lib/xercesImpl.jar:/jellly/boilerpipe-1.1.0/boilerpipe-1.1.0.jar:/jellly/boilerpipe-1.1.0/lib/nekohtml-1.9.13.jar:/jellly/boilerpipe-1.1.0/lib/xerces-2.9.1.jar

I'd recommend against trying to guess the module name we put under Java::, since for unusual packages it can get mangled pretty badly. Use java_import 'your.weird.package.ArticleExtractor' or if all the package components are compatible with Ruby method naming, you can also do Java::your.weird.package.ArticleExtractor.
Also, since you might run into this... you'll want to reference the INSTANCE variable as ArticleExtractor::INSTANCE, since we map it as a Ruby constant.
Have fun!

You can also use the nice Jruby Boilerpipe Gem which wraps the Java code
Or the pure ruby implementation of Boilerpipe Ruby Boilerpipe Gem
require 'boilerpipe'
Boilerpipe::Extractors::ArticleExtractor.text("https://github.com/jruby/jruby/wiki/AboutJRuby")

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.