# ComfyJ Programmer's Guide Version: 2.1 Last Updated: April 04, 2006 Copyright © 2002-2006 TeamDev Ltd. # Chapter 1. Introduction ComfyJ is a product for Java-to-COM and COM-to-Java integration. Java-to-COM integration allows a Java application to easily integrate with any COM/OLE/OCX/ActiveX libraries in pure Java without writing any native code. The following features are available in this version of ComfyJ: Wrappers for all standard COM interfaces, such as `IUnknown`, `IDispatch`, etc. Support for standard COM types, such as `Variant`, `SafeArray` (single and multi-dimensional arrays), `BStr`, etc. Support for VTBL method calling mechanism. You can invoke COM object methods by using function index. Automation support enabling you to: Invoke any method of a COM object by using a dynamic method invocation technique. Get any property of the COM object, including indexed and named ones. Set COM object properties. Support for COM events. You have the ability to create a Java COM event handler and connect it to a COM object using a standard (findConnectionPoint/advise) COM technique. Embedding any OLE/OCX/ActiveX controls into a Swing application. ComfyJ provides a special `OleContainer` class allowing you to: Create an embedded object using ProgID, CLSID, or from a file. Also, there is a way to insert an IOleObject into the container. Embed various OLE/OCX/ActiveX components, such as Internet Explorer, Acrobat Reader, Microsoft Office documents, and various media components such as Windows MediaPlayer, DVD player, QuickTime, ShockwaveFlash, etc. Perform static drawing of an embedded component. Save/Load an embedded OLE Object to/from a file in a special binary format. Do various kinds of in-place activation such as SHOW, INPLACEACTIVE, etc. DCOM support. ComfyJ allows creating COM objects on a remote server. Support for different threading models. CodeGenerator application. This specially designed application allows you to generate Java COM wrappers for custom COM objects. Generated classes can be compiled and packed to a JAR file, if necessary. COM-to-Java integration allows you to implement and expose Java COM objects as usual COM objects in pure Java without writing any native code. In this version of ComfyJ you can use the following features: `IUnknownServer` - The server implementation of the `IUnknown` COM interface. All custom Java COM objects that implement the `IUnknown` COM interface can be derived from this class. `DispatchServer` - The server implementation of the `IDispatch` COM interface. All custom Java COM objects that implement the `IDispatch` COM interface can be derived from this class. Ability to create and register custom Java COM classes at run time. This technique is widely used in the implementation of `OleContainer` (see item 6 on the list above) and in COM events support (see item 5 on the list above). ServerManager application. This application allows you to create any custom COM classes and register them as COM servers in the system registry. ## 1.1. Prerequisites ComfyJ is based on JNIWrapper and WinPack products developed by TeamDev. Therefore, to start effectively using ComfyJ, you need to have basic knowledge of JNIWrapper and WinPack API. You can find the documentation on these products online. We recommend you to start with JNIWrapper Programmer's Guide. To get the full package of JNIWrapper and WinPack, including samples' source code, please download the full JNIWrapper distribution. ## 1.2. Related Documents The documents provided on the Documentation page at the JNIWrapper site (http://www.jniwrapper.com) are intended to help you in understanding and effective use of ComfyJ. We suggest that you read the ComfyJ documentation in the following order: You can start with this Programmer's Guide that describes the basics and underlying ideas of ComfyJ. To get some hands-on experience in using ComfyJ, you can proceed from this Programmer's Guide to ComfyJ Tutorial You can also find helpful information in Frequently Asked Questions that we regularly update based on the questions we get from our users. You can access them online at the JNIWrapper site. # Chapter 2. Getting Started ## 2.1. ComfyJ Distribution Overview The ComfyJ distribution includes: ComfyJ library. This library provides Java and COM integration functionality. JNIWrapper library. This is the core library of Java-to-Native integration for Windows. WinPack library. This is the library for Windows Desktop integration. Code Generator application. This application allows you to generate Java wrappers for interfaces and coclasses of the specified component, type library or module. Java COM ServerManager. The application is designed for registering and removing COM servers written in Java using ComfyJ. ## 2.2. System Requirements The following are the general requirements for running ComfyJ on the supported platforms: OS: Windows 9x, Me, NT 4.0, 2000, XP and 2003. Java: Java 2 SDK/JRE 1.3.x and higher. For Code Generator GUI mode, the preferred JDK is 1.4.2 or higher. There are no specific memory or other hardware requirements for developing an application based on ComfyJ. ## 2.3. Package Contents The ComfyJ package consists of the following main files required for work: Library JAR file - `comfyj-<version>.jar`, where <version> is the product version, for example "2.0". JNIWrapper library - `jniwrap-<version>.jar`, where <version> is the product version. WinPack library - `winpack-<version>.jar`, where <version> is the product version. Native code library JNIWrapper native library - `jniwrap.dll` License files JNIWrapper developer's license - `jniwrap.lic` ComfyJ developer's license - `comfyj.lic` The Code Generator application has the following related libraries: Code Generator application - `comfyj-generator-<version>.jar`, where <version> is the product version. Velocity library - `velocity-dep-1.3.1.jar` is used for creating template-based Java wrappers. Commons library - `commons-cli-1.0.jar` is used for parsing command-line parameters. The Java COM ServerManager application is based on the following: ServerManager library - `comfyj-svrmanager-<version>.jar`, where <version> is the product version. Note that all the files need to be placed in the appropriate locations. For more details about the product installation instructions, see the section "Configuring Software". The package may also contain other files providing some useful information for the user, for example the `Readme.txt` file. # Chapter 3. Configuring ComfyJ As mentioned earlier, ComfyJ consists of six main files required for the software functioning: JAR files, native code library, and license files. The following sections describe where each file should be located. No other configuration is required. ## 3.1. Library JAR Files The ComfyJ, JNIWrapper and WinPack JAR files should be located in the program classpath. Due to the limitations of the Java native library loading mechanism, it is not recommended to load ComfyJ in custom class loaders unless you are sure that it will be loaded in only one such class loader. The library files can also be placed on the boot class path or in the extension directory of Java runtime, but this is not required. ## 3.2. Native Code Library The JNIWrapper native code library is loaded using the standard Java native code loading mechanism. There are no known problems with placing the native code library file on a mapped drive or even using it from the network share using a UNC path.
| Do not rename the library file, or else it will not be loaded.
Even though the native code library can be placed virtually anywhere, its actual location should be specified considering the fact that Java code should find the library to load. It can be placed somewhere within the program library search path (value of the `java.library.path` system property, which is by default equal to the value of the system variable PATH on Windows). Alternatively, you can add a search path to the default library loader used by JNIWrapper or even write a custom one that searches for native code in a predefined location. Using the default path may be preferable for development and the library loader as a much better way for distributing a complete application. The `jniwrap.dll` can be placed in any JAR library from the application classpath, but not in the `META-INF` subfolder. You may want to install the native code library into the directories on the default system path, for example the root of Windows installation or Windows\System32. Note that this requires having appropriate access rights to the Windows NT/2000/XP system. Installing the native code library using this way may be convenient, but is not a required procedure. ## 3.3. License Files Placing the license files is very simple: They need to be located in the same directory as the native code library file.
| Do not rename the license files, or else they will not be recognized.
Alternatively, the license files can be placed in the `META-INF` folder of any JAR library from the application classpath. # Chapter 4. Using COM Integration The functionality of ComfyJ COM integration is based on run-time classes that come in the core library and code generated for specific COM objects of your application. Although it is possible to work with COM/OLE objects via COM/OLE Automation (see the section "Using COM/OLE Automation" ), which does not require generating code, for complex integration tasks it is much more convenient to work with API generated for COM functionality by Code Generator (see the section "Code Generator Application"). ## 4.1. COM Support Initialization and Shutdown Each Java thread that invokes COM functions and works with COM classes should initialize a COM library at the beginning of its lifecycle and uninitialize it at the end. ### 4.1.1. COM Memory Management in JNIWrapper All COM resources as well as other native resources that are allocated by JNIWrapper are garbage-collected automatically by JNIWrapper's NativeResourceCollector (NRC). NRC starts automatically on the application startup and runs permanently while the application runs. There is no need to call the `addRef()` and `release()` methods. The `addRef()` method is called when an object is created and the `release()` method is called automatically when the instance is not used any more by NRC. Also, when an instance of some COM class is created, it is automatically registered in NRC. Alternatively, there is an ability to control the process of instance deallocation by setting its `AutoDelete` property to `false` using the `setAutoDelete(false)` method. The example below demonstrates how to do this:
    IUnknownImpl object = getObject();
    object.setAutoDelete(false);
    try {
    // do something with the object here
    } finally {
    object.release();
    }
### 4.1.2. Initializing COM The initialization should be called at least once for each thread that uses the COM classes or functions. You can do this by invoking one of the following methods: `ComFunctions.coInitialize()`- initializes the COM library in the current thread and identifies the concurrency model as a single-threaded apartment (STA). It corresponds to the `CoInitialize` native function. `OleFunctions.oleInitialize()` - is similar to `coInitialize()` and corresponds to the `OleInilialize` native function. `ComFunctions.coInitializeEx(CoInit value)` - initializes the COM library in the current thread with the passed concurrency model. #### 4.1.2.1. Concurrency Models To specify a concurrency model different from single-threaded apartment, use the `coInitializeEx()` method that takes a specified concurrency model as a parameter. There are four concurrency models available from the `CoInit` enumeration that can be used for initialization: `MULTITHREADED` `APARTMENTTHREADED` `DISABLE_OLE1DDE` `SPEED_OVER_MEMORY`. Most of the COM/ActiveX objects use the `APARTMENTTHREADED` model. You can read about the concurrency model requirements in the documentation of your COM object, or check the value of the `ThreadingModel` key in the Windows Registry corresponding to your class. ### 4.1.3. Performing Clean-up The COM support should be uninitialized when the application shuts down. To uninitialize the COM integration, `OleFunctions.oleUninitialize()` should be called if initialization was performed by `oleInitialize()`; otherwise `ComFunctions.coUninitialize()` should be used. Both these methods do the following: Close the COM library in the current thread. Free allocated resources. Release any class factories or services. ## 4.2. Using COM in Multi-Threaded Applications As said earlier, COM objects can be accessed only from the thread that initialized COM integration. In multi-threaded applications, it may be necessary to work with COM objects from multiple threads. This can be achieved by having a single thread for invoking COM methods so that other Java threads post actions for execution. JNIWrapper provides the `OleMessageLoop` class for this purpose. ### 4.2.1. `OleMessageLoop` Class The `com.jniwrapper.win32.automation.OleMessageLoop` class provides implementation for the COM dispatch thread and methods for starting and stopping the loop thread, and invoking COM functions in this thread. ### 4.2.2. Invoking COM Methods Without Return Values If a COM function you intend to invoke does not return results or you are not interested in returning these results to the calling thread, you can add the ``Runnable`` action to the execution queue of the `OleMessageLoop` class.
    ...
      Runnable action = new Runnable() {
         public void run()
         {
           // working with COM here
         }
      };
      OleMessageLoop.addAction(action);
    ...
The calling thread will continue its execution after the `addAction()` call. The action will be run after all actions already set in the queue are executed. ### 4.2.3. Invoking COM Methods with Return Values Returning values to the calling thread is a bit more complicated. To do this, the following steps should be performed: A method that deals with a COM object should be implemented in the class that requests the execution from `OleMessageLoop`. Later, this method will be invoked in the COM thread using reflection. Request invocation of the wrapper method (created during the previous step) by calling the `OleMessageLoop.invoke()` method with the following parameters: Caller instance Function name Function parameters After the function call is requested, the calling thread will wait until the function returns the result. The following example demonstrates this invocation technique:
    public class Test
    {
      private _PropertyReaderImpl _pr = null;
      public Test()
      {
         _pr = (_PropertyReaderImpl)OleMessageLoop.invokeMethod(
          this, // caller
          "createPropertyReaderClass", // function name
          new Object[]{ // parameters
          new ClsCtx(ClsCtx.CLSCTX_INPROC_SERVER)});
      }

      public Object createPropertyReaderClass(ClsCtx dwClsContext)
      {
         final _PropertyReaderImpl prClass = PropertyReader.create(
                               dwClsContext);
         return prClass;
      }
    }
### 4.2.4. Displaying Errors By following the rules mentioned in the previous sections, you should achieve stable COM integration in your application. Generally, if code appears to be non-working, `ComException` is thrown with the error code `0x800401f0`:
    com.jniwrapper.win32.com.ComException: COM object method returns error code: -->
    --> Unknown code(0x800401f0)
If you get such an exception, please verify that your code is written according to the COM integration guidelines described in this document. ### 4.2.5. Creating New OLE Message Loop Thread The `OleMessageLoop` class can be used as a singleton or as an ordinary class. Every instance of `OleMessageLoop` reflects to its own thread. `OleMessageLoop` has a static `getInstance()` method that allows you to access a single `OleMessageLoop` instance. There are three public constructors for creating `OleMessageLoop` instances. When an `OleMessageLoop` instance is created, the message loop thread is not started yet. It should be started manually by calling the `OleMessageLoop.doStart()` method. A message loop thread can be a daemon (by default) or not. Use the `OleMessageLoop(boolean)` constructor to specify whether the thread is a daemon:
        //Creating a daemon message loop thread
        OleMessageLoop oleMessageLoop = new OleMessageLoop(true);
        //Starting the thread
        oleMessageLoop.doStart();
### 4.2.6. Invoking Functions Synchronously Use `OleMessageLoop.doInvokeAndWait()` (or static `OleMessageLoop.invokeAndWait()` for a singleton) to execute code in the message loop thread synchronously:
        Runnable runnable = new Runnable()
        {
            public void run()
            {
                _Workbook workbook = new _WorkbookImpl(oleContainer.getOleObject());
                String name = workbook.getName().getValue();
                System.out.println("Workbook name = " + name);
            }
        };
        try
        {
            oleMessageLoop.doInvokeAndWait(runnable);
        }
        catch (InterruptedException e)
        {
            e.printStackTrace();
        }
        catch (InvocationTargetException e)
        {
            e.printStackTrace();
        }
Any exceptions that are thrown in executing code are wrapped into the `InvocationTargetException` class. Call the `InvocationTargetException.getCause()` method to get the original exception. ### 4.2.7. Invoking Functions Asynchronously Use `OleMessageLoop.doInvokeLater()` (or static `OleMessageLoop.invokeLater()` for a singleton) to execute code in the message loop thread asynchronously:
        Runnable runnable = new Runnable()
        {
            public void run()
            {
                OleContainer oleContainer = new OleContainer();
                oleContainer.createObject("Excel.Sheet");
                _Workbook workbook = new _WorkbookImpl(oleContainer.getOleObject());
                String name = workbook.getName().getValue();
                System.out.println("Workbook name = " + name);
            }
        };
        oleMessageLoop.doInvokeLater(runnable);
### 4.2.8. Binding Objects to OLE Message Loop Thread `OleMessageLoop` provides the ability to invoke all methods of an object in the OLE message loop thread using the binding operation:
        //Creating a new _Workbook instance in the OLE message loop thread
        Runnable runnable = new Runnable()
        {
            public void run()
            {
                workbook = new _WorkbookImpl(oleContainer.getOleObject());
            }
        };
        try
        {
            oleMessageLoop.doInvokeAndWait(runnable);
        }
        catch (InterruptedException e)
        {
            e.printStackTrace();
        }
        catch (InvocationTargetException e)
        {
            e.printStackTrace();
        }

        //Binding the workbook object
        workbook = (_Workbook) oleMessageLoop.bindObject(workbook);
        //Invoking a workbook function in the OLE message loop thread
        String name = workbook.getName().getValue();
If the method of a bound object returns an object, the returned object is not bound to the OLE message loop thread:
        //Binding the workbook object
        workbook = (_Workbook) oleMessageLoop.bindObject(workbook);
        //Invoking a workbook function in the OLE message loop thread.
        //The sheets object is not bound
        Sheets sheets = workbook.getSheets();
        //Binding the sheets objects
        sheets = (Sheets) oleMessageLoop.bindObject(sheets);
## 4.3. Exposing COM to Java To implement a Java COM class, the following steps should be performed. ### 4.3.1. Creating Server Implementation Create a Java class that extends the `IUnknownServer` class and implements required COM interfaces as shown in the example below:
    // COM class implementation
    public static class OleClientSiteImpl extends IUnknownServer
        implements IOleClientSite,
                IOleInPlaceSite,
                IOleDocumentSite,
                IOleWindow,
                IOleInPlaceFrame
    {
        ...
    }
If your server-side implementation of a COM object needs to provide automation functionality via the `IDispatch` interface, you can derive your class from `IDispatchServer` that provides default implementation. ### 4.3.2. Creating Class Factory Create a class factory server for a given COM class implementation:
    // Creating a class factory server for our COM class
    IClassFactoryServer oleClientSiteClass =
      new IClassFactoryServer(OleClientSiteImpl.class);
`IClassFactoryServer` will automatically register the interfaces that are implemented by the specified class and its parents. If the class (`OleClientSiteImpl` in the example above) extends `IDispatchServer`, the default interface will be automatically set to `IDispatch`; otherwise the default interface will be set to `IUnknown`. If you need to specify a custom default interface, call the `IClassFactoryServer.setDefaultInterface()` method:
    // register a default interface for our COM class
    oleClientSiteClass.setDefaultInterface(IOleClientSite.class);
And finally, retrieve a class factory from the class factory server instance:
    IClassFactoryImpl classFactory =
                          oleClientSiteClass.createIClassFactory();
### 4.3.3. Creating Instances Now that you have the instance of the class factory, you can use it to create an instance of your COM class using the following example:
    IOleClientSiteImpl oleClientSite = new IOleClientSiteImpl();
    classFactory.createInstance(null, oleClientSite);
The `null` parameter above means that the object is not created as part of an aggregate. Pass a valid `IUnknown` instance instead of `null` if you work with aggregates. ## 4.4. Using COM/OLE Automation In some cases, it is necessary to invoke COM class functions or set and get properties having only the `IUnknown` instance and knowing the function name and its parameters or just a property name and its type: For example, if a COM class was instantiated by GUID. For these cases, ComfyJ provides the ability to invoke functions via the `IDispatch` interface. This technique is called Automation and is handled in ComfyJ by the `com.jniwrapper.win32.automation.Automation` class. ### 4.4.1. `Automation` Class You can invoke a method of a dispatchable object using the `invoke()` method of the `com.jniwrapper.win32. automation.Automation` class. Setting and getting properties is done using the `setProperty()` and `getProperty()` methods, respectively. All calls to this "automated" class are performed in its OLE message loop thread. The following example demonstrates this.
    // retrieve the dispatched interface
    IUnknownImpl dispatchable = getDispatchable();
    String fileName = getFileName();

    // create an Automation for instance
    Automation automation = new Automation(dispatchable);

    // set the COM object property using automation
    automation.setProperty("FileName", fileName);

    // invoke the COM object method using automation
    automation.invoke("LoadFile", new Object[] {fileName});
## 4.5. Using OCX Components Without GUI You can work with OCX components without embedding them into OleContainer. The following code sample shows how to do it.
    IUnknown ocxComponentWrapper = ...;

    IOleObjectImpl oleObject = new IOleObjectImpl(ocxComponentWrapper);

    // Initialize storage
    ILockBytesImpl lockBytes = (ILockBytesImpl)
            StorageFunctions.createILockBytesOnHGlobal(new GlobalMemoryBlock(), true);
    IStorage storage = StorageFunctions.stgCreateDocfileOnILockBytes(lockBytes,
            new StgMode(StgMode.STGM_READWRITE |
            StgMode.STGM_SHARE_EXCLUSIVE | StgMode.STGM_CREATE),
            new Int32());

    // Initialize persist storage
    IPersistStorageImpl persistStorage = new IPersistStorageImpl();
    oleObject.queryInterface(persistStorage.getIID(), persistStorage);
    persistStorage.initNew(storage);
## 4.6. Embedding ActiveX/OLE Components into Swing Applications ComfyJ provides custom client-side implementation of the OLE container that allows embedding ActiveX/OLE controls into Swing applications. ComfyJ provides its own implementation of the OLE container. There is a special `com.jniwrapper.win32.automation.OleContainer` class that represents a usual AWT component and is designed to embed various OLE/ActiveX components into Java Swing/AWT applications. `OleContainer` acts as a host site for OLE objects. It can create an OLE object by ProgID, CLSID, or from a file. Also, it provides the ability to insert an externally initialized OLE object into the container. The communication with a created OLE object is handled using the default OLE verbs. ### 4.6.1. Displaying Java Menus over ActiveX Component In many cases, it is necessary to display Java menus over an ActiveX component embedded into OleContainer. However, by default all Java menus are "lightweight" and cannot be displayed over the "heavyweight" ActiveX components. To solve this problem, just add the following piece of code to your program:
    JPopupMenu.setDefaultLightWeightPopupEnabled(false);
## 4.7. Registering Callbacks for Generated COM Components (COM Events Handling) This section describes the way of implementing custom event handlers for ActiveX components. In many cases, it appears necessary to be notified about events in a COM component and to handle them somehow. Normally, for this purpose, COM components provide so-called connection points. Connection points allow attaching custom event handlers by using their `advise()` and `unadvise()` methods. Such event handlers are usually defined as dispatch interfaces in the type library. You can see how to do this using ComfyJ and generated stubs for a COM component in the samples below. They demonstrate how to attach a custom event handler (implementing the `DWebBrowserEvents2` dispinterface) to the `WebBrowser` ActiveX component embedded in OleContainer. Note that in order to execute the samples, you need to generate Java stubs for the `WebBrowser` component using the Code Generator application. Among the generated files, you will find three files that correspond to the `DWebBrowserEvents2` dispinterface, namely `DWebBrowserEvents2`, `DWebBrowserEvents2Impl`, and `DWebBrowserEvents2Server` classes. As mentioned earlier, `DWebBrowserEvents2` is a Java interface, `DWebBrowserEvents2Impl` is the default implementation of the `DWebBrowserEvents2` interface, and `DWebBrowserEvents2Server` is a server adapter for that interface. The technique of advising custom event handler is quite simple:
    // Create IConnectionPointContainer to ActiveX object
    //that is embedded in OleContainer
    IConnectionPointContainer connectionPointContainer =
            new IConnectionPointContainerImpl(container.getOleObject());
    // Find a necessary connection point
    IConnectionPoint connectionPoint =
            connectionPointContainer.findConnectionPoint(new IID(
                              DWebBrowserEvents2.INTERFACE_IDENTIFIER));
    // Advise our handler
    connectionPoint.advise(handler);
The handler itself is an instance of the `DWebBrowserEvents2Handler` class and is created as shown below:
    public class DWebBrowserEvents2Handler extends DWebBrowserEvents2Server {
        public static final String PROPERTY_STATUS = "status";
        public static final String PROPERTY_PROGRESS = "progress";
        private final PropertyChangeSupport _propertyChangeSupport =
                                          new PropertyChangeSupport(this);
        public DWebBrowserEvents2Handler(CoClassMetaInfo info) {
            super(info);
        }
        public void statusTextChange(BStr /*[in]*/ Text) {
            _propertyChangeSupport.firePropertyChange(PROPERTY_STATUS,
                                                     "", Text.getValue());
        }
        public void progressChange(Int32 /*[in]*/ Progress, Int32 /*[in]*/ ProgressMax)
        {
            _propertyChangeSupport.firePropertyChange(PROPERTY_PROGRESS,
                    ProgressMax,
                    Progress);
        }
        public void addPropertyChangeListener(PropertyChangeListener listener) {
            _propertyChangeSupport.addPropertyChangeListener(listener);
        }
    }
As you can see, the `DWebBrowserEvents2Handler` class handles only two events - ``statusTextChange`` and ``progressChange`` - and notifies the registered Java property change listeners. But any other events can also be handled in the same way by overriding the appropriate methods of the `DWebBrowserEvents2Server` class. Also take notice that if you wish to have an inner event handler class, you shall make it `static`. For example, if you declare the `DWebBrowserEvents2Handler` class inside any other class, you shall declare it as `public static class DWebBrowserEvents2Handler`. Since `DWebBrowserEvents2Handler` is a Java COM class, it should be created using `ClassFactory`. The technique and principles of creating Java COM objects are described in the above sections. You should bear in mind, however, that `DWebBrowserEvents2` is not a dual dispatch interface because it does not have a corresponding VTBL. Its methods are invoked only using the `IDispacth.invoke()` method by predefined `dispIDs` for each method of the dispinterface. Therefore, we will use the following technique for creating a handler:
        // Create a class factory server for DWebBrowserEvents2Handler
        IClassFactoryServer server =
                         new IClassFactoryServer(DWebBrowserEvents2Handler.class);
        IClassFactory factory = server.createIClassFactory();

        // Create an instance of DWebBrowserEvents2Handler with a class factory
        IDispatchImpl handler = new IDispatchImpl();
        factory.createInstance(null, handler.getIID(), handler);

        // Get the new instance of Java COM object from the server
        DWebBrowserEvents2Handler webBrowserEvents2Handler =
                             (DWebBrowserEvents2Handler)server.getInstances().pop();
        // Add a property change listener to monitor property changing
        webBrowserEvents2Handler.addPropertyChangeListener(new PropertyChangeListener()
        {
            public void propertyChange(PropertyChangeEvent evt)
            {
                    //your handling goes here
            }
        }
Using this technique, you can create your custom event handlers virtually for any COM component. In some cases, it is necessary to register an event handler interface and the IDispatch interface in the instance of `IClassFactoryServer`, like shown below:
    server.registerInterface(IDispatch.class, new IDispatchVTBL(server));
    server.registerInterface(DWebBrowserEvents2.class, new IDispatchVTBL(server));
Such additional registration is necessary because some `ConnectionPoint` implementations do not accept a handler that implements the `IDispatch` interface only and throws the `CONNECT_E_ADVISELIMIT` COM exception. # Chapter 5. Code Generator for ComfyJ ## 5.1. Running Code Generator As the name of the Code Generator application suggests, its purpose is to generate Java code for COM, OLE and ActiveX objects. You can start the program by running `CodegenForComfyJ.bat` from the `bin` folder of ComfyJ installation. `CodegenForComfyJ.bat` takes the following parameters: `GUID` of the type library or `ProgID` of one of the components that belongs to the library. Version of the library. Destination folder for generated sources. Root package name for Java source code to be generated. Optional parameter `-disp` for generating stubs of dispatch interfaces. Note that the parameters should appear in the command line in the order listed above. Below are given command-line examples:
    CodegenForComfyJ.bat guid 00062FFF-0000-0000-C000-000000000046 9.2 src outlook
    CodegenForComfyJ.bat progid shell.explorer 1.1 src explorer -disp
### 5.1.1. Running Code Generator in GUI Mode Apart from the command-line version, you can work with Code Generator in GUI mode. To start a GUI-based program, run `CodegenForComfyJ.bat` without any parameters. ### 5.1.2. Detecting GUID, ProgID and Version Normally, GUIDs are declared in documentation for COM objects. If you don't have the GUID for the COM library, you may want to search for it in Windows Registry under:
    HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID
The type library can hold multiple versions of COM objects. Like with GUID, consult the documentation for the correct version number. ## 5.2. Namespaces and Package Naming The destination root package passed to Code Generator in the command line is actually the root for other subpackages automatically generated by the application. The program generates a subpackage for each namespace it detects in the specified type library. For example, if the type library defines two namespaces `outlook` and `office`, you would have the following package structure:
    mypackage
    mypackage.outlook
    mypackage.office
If there are no namespaces defined in the type library, the code will be generated under the passed package.
| In this document, the term root package will be used to designate a package created for a namespace (if defined), or the package specified in the command line if namespaces are not used.
## 5.3. Generated Code Structure The Code Generator application produces the code described in the following sections. ### 5.3.1. Structures, Unions, Enumerations These data type classes are created in the root package. ### 5.3.2. Interfaces Interfaces are created in the package root. The code for each interface defines methods for corresponding COM interface and the interface identifier. ### 5.3.3. Implementation Classes The Java code for each generated COM interface is accompanied by the implementing classes. These classes serve as client-side code for invoking methods of corresponding COM interfaces. These classes are generated under the `impl` subpackage. Each implementation class contains a constructor that takes `IUnknown` as a parameter. Using this constructor, you can cast one interface to another if it is implemented by the COM class you integrate with. This is similar to calling the `QueryInterface()` COM method. ### 5.3.4. CoClasses The Microsoft COM documentation defines a class as "an implementation that allows QueryInterface between a set of interfaces" (see "Platform SDK: Microsoft Interface Definition Language (MIDL)"). Code Generator creates classes derived from `com.jniwrapper.win32.com.CoClass` for each coclass found in the type library. Coclasses serve as a factory for objects that implement default interfaces associated with the coclass. Each CoClass provides methods with the following signatures:
    public static DefInterface create(ClsCtx dwClsContext)
                                           throws ComException;

    public static DefInterface queryInterface(IUnknown unknown)
                                           throws ComException;
where `DefInterface` is the default interface associated with the coclass. The `create()` method creates an object implementing the default interface of the coclass. The parameter passed to the method designates the execution context for the class. The `queryInterface()` method allows to get the default interface from the existing COM object passed as `IUnknown`. ### 5.3.5. VTBL Classes JNIWrapper provides the ability to expose a Java class as a COM object, so it can be called by the native side of the integrated application. VTBL classes provide callbacks for the native side code exposing a Java class as a COM object. For more information on calling Java from native side, please see the section "Exposing COM to Java". # Chapter 6. COM to Java Integration ## 6.1. Developing Java COM Servers To create your Java COM server means to develop your own Java class that extends the `com.jniwrapper. win32.com.DispatchComServer` class. This class should implement at least one interface. You can access only the methods listed in the interfaces the class implements as the COM server methods. So you can implement any of the existing interfaces (like `IPersist`) or develop your own one. However, the current implementation of Java Com servers supports only dispatch custom interfaces. This means that you can interact with the Java COM object via custom interfaces using the Automation technology only.
| In the current version of ComfyJ, no properties of COM servers are supported.
### 6.1.1. Developing Java Dispinterface When developing Java dispinterfaces, please pay attention to the following: Custom interfaces should derive from the `com.jniwrapper.win32.automation.IDispatch` interface. The return values and arguments of the dispinterface methods should be of JNIWrapper types (such as `DoubleFloat` or `BStr`). Your Java interfaces will not be available as regular COM interfaces. The sample dispinterface is shown below:
    public interface ISample extends IDispatch
    {
        public BStr getProgId();
    }
For the full code sample, please see `ComToJava/src/ISample.java` ### 6.1.2. Developing Java COM Server Class A Java COM server class should implement all the interfaces you want to provide in your COM server. When developing a Java COM server, pay attention to the following: This class should declare `COM_SERVER_CLSID` as the `public static final` field that describes your COM server's globally unique class identifier (CLSID). In the same way, it can also declare `PROG_ID`, `VERSION_INDEPENDENT _PROG_ID` and `COM_SERVER_DESCRIPTION`, but only `CLSID` is required. The return values and attributes of the methods should be of JNIWrapper types (such as `DoubleFloat` or `BStr`). Here is the example of the COM server class:
    public class JavaComServerSample extends DispatchComServer implements IPersist, ISample
    {
        public static final CLSID COM_SERVER_CLSID =
             new CLSID("{A35B432E-5274-4146-9858-638313EDCEA6}");
        public static final String PROG_ID = "jniwrapper.comtojavasample.1";

        public void getClassID(CLSID pClassID) throws ComException
        {
            pClassID.setData1(COM_SERVER_CLSID.getData1());
            pClassID.setData2(COM_SERVER_CLSID.getData2());
            pClassID.setData3(COM_SERVER_CLSID.getData3());
            pClassID.setData4(COM_SERVER_CLSID.getData4());
        }

        public BStr getProgId()
        {
            return new BStr(PROG_ID);
        }
    }
For the full code sample, see `ComToJava/src/JavaComServerSample.java` ## 6.2. Registering Java COM Servers Before the Java COM server can be used, it should be registered in the Windows Registry. The necessary configuration can be done with the help of ComfyJ ServerManager application or using ComfyJ API directly. During the registration, paths to all the necessary Java libraries are saved in the Windows Registry. Note that the Java COM server should have access to all the ComfyJ necessary libraries and core files. For more information on the necessary libraries and files, please refer to the section Configuring Software. Also consider that the CLASSPATH can not be very long, so if you want to add a huge number of JARs you shall use the following workaround. You put a list of JARs separated by one or more spaces as a value of the Class-Path attribute in the manifest file (`Manifest.mf`). Then you put this file to the `META-INF` folder at the root of any other JAR which shall be added to the CLASSPATH of the server. Look at the following code as an example of the manifest file. Note that jniwrap-3.0.jar, comfyj-2.0.jar, winpack-3.0.jar and jniwraplib.jar are in the same folder as the deafult.jar, which contains the following manifest file.
    Manifest-Version: 1.0
    Class-Path: jniwrap-3.0.jar comfyj-2.0.jar winpack-3.0.jar jniwraplib.jar
### 6.2.1. ComfyJ ServerManager: Registering in Command-Line Mode The ServerManager application allows you to register the Java COM server using the command line. If you run `ServerManager.bat` with the "/?" or "-h" paramater, you will see a quick guide to using the program in console mode:
    Usage 1: Command line mode

        Registering Java COM server
        ---------------------------------
        Usage: ServerManager.bat serverClassName -classpath classpath [-jvm jvmPath]

           serverClassName    Java COM server class name.
           classpath          Classpath that will be used for running the server.
                              Make sure that classpath includes jniwrap.jar, comfyj.jar,
                              and winpack.jar libraries.
           jvmPath            Optional. Specifies the JVM (java.exe or javaw.exe) that
                              will be used for running the server. If it is not defined,
                              the default JVM will be used.

        For example: ServerManager.bat com.project.MyServer
                          -classpath "c:/MyServer/jniwrap.jar;c:/MyServer/comfyj.jar;
                                c:/MyServer/winpack.jar;c:/MyServer/myserver.jar"
                          -jvm "c:\j2sdk1.4.2_06\bin\javaw.exe"

        Unregistering Java COM server
        ---------------------------------
        Usage: ServerManager.bat -unregister {serverClassName -classpath classpath
                      or -clsid clsid}

           serverClassName    Java COM server class name to be unregistered.
           classpath          Classpath of the server.
           clsid              Class ID (CLSID) of a Java COM server to be unregistered.

        For example (by class): ServerManager.bat -unregister com.project.MyServer
                                -classpath "c:/MyServer/jniwrap.jar;c:/MyServer/comfyj.jar;
                                         c:/MyServer/winpack.jar;c:/MyServer/myserver.jar"
        For example (by clsid): ServerManager.bat -unregister
                                     -clsid {A35B432E-5274-4146-9858-638313EDCEA6}

    Usage 2: To run ServerManager GUI, start without parameters.
If you want to register the Java COM server, make sure to specify the fully qualified class name and the classpath to be used for running this server. Note that the classpath should include at least the `jniwrap.jar`, `comfyj.jar` and `winpack.jar` libraries and the library that contains the specified COM server. The ServerManager application allows you to unregister the server by its class name or by its globally unique class identifier (CLSID). If you unregister the COM server by its class name, you need to specify the full classpath of the server too (the `-classpath` parameter). Unregistering the COM server by CLSID doesn't require any additional information. ### 6.2.2. ComfyJ ServerManager: Registering in GUI Mode Start the ServerManager application using the `bin/ServerManager.bat` file from the ComfyJ distribution. When the application is opened, follow these steps: In the upper part of the window, click the Load From button to load Java COM servers from a JAR library or directory. All COM servers from the specified path are displayed in Server List. If the selected server is registered, its details appear read-only; otherwise you can edit the server's startup parameters on the right. In the CLASSPATH area, click the Add JAR/Directory button to add necessary libraries and directories that are specific to this server only. In the CLASSPATH area, click the Add from Common button to add necessary libraries and directories from the list of common libraries. These can be at least `jniwrap.jar, winpack.jar` and `comfyj.jar` libraries. The dialog box that appears allows editing the list of common libraries. This list will be saved to the `manager.properties` file in the working directory of the ServerManager application. Select the server you want to register and click the Register button. Also, you can remove the Java COM Server from the Windows Registry by selecting the appropriate server from the list and clicking the Unregister button. If you need to list all Java COM servers registered in the system, click the List Registered button. ### 6.2.3. Registering at Run Time You can also register the Java COM Server object at run time of the program using the `registerComServer()` method and the `com.jniwrapper.win32.tools.RegisterDispatchComServer.ComServerDescriptor` class. In this case, you need to create an instance of the `ComServerDescriptor` class and pass it to the `registerComServer()` method. Take a look at the following code as the example of the run-time component registration and its further usage:
    public class RuntimeRegistrationSample
    {
        public static void main(String[] args) throws Exception
        {
            String classPath =
                  "C:\\JavaComServer\\comfyj.jar;" +
                  "C:\\JavaComServer\\jniwrap.jar;" +
                  "C:\\JavaComServer\\winpack.jar;" +
                  "C:\\JavaComServer\\classes";

            RegisterDispatchComServer.ComServerDescriptor descriptor =
                    new RegisterDispatchComServer.ComServerDescriptor
                            (JavaComServerSample.class, "C:\\JavaComServer\\classes",
                                    System.getProperty("jvm.path"), classPath, null, false);
            RegisterDispatchComServer.registerComServer(descriptor);

            Runnable runnable = new Runnable()
            {
                public void run()
                {

                    IDispatch dispatch =
                     new IDispatchImpl(CLSID.createFromProgID
                             ("jniwrapper.comtojavasample"), ClsCtx.LOCAL_SERVER);

                    IPersistImpl p = new IPersistImpl(dispatch);
                    CLSID clsid = new CLSID();
                    p.getClassID(clsid);
                    System.out.println("ClassID = " + clsid);

                }
            };
            OleMessageLoop.invokeAndWait(runnable);
            OleMessageLoop.stop();

        }
    }
## 6.3. Using Java COM Servers You can use the Java COM Servers as usual native COM servers. Let's consider the usage of the previous sample COM server in different programming languages. ### 6.3.1. Java Client If you want to use the Java COM server via a standard interface (like `IPersist`), you can access its methods by creating the appropriate implementing object (like `IPersistImpl`, see the sample code below) and calling its methods. To interact with the Java COM sever via a custom interface, you need to use the `com.jniwrapper.win32.automation.Automation` class. In this case, the arguments of all the custom interface's methods and their return values are of the automation-specific types, so you need to wrap all the values into `com.jniwrapper.win32. automation.types.Variant`s.
    public class JavaComClientSample
    {
        public static void main(String[] args) throws Exception
        {
            Runnable runnable = new Runnable()
            {
                public void run()
                {
                    IDispatch dispatch =
                     new IDispatchImpl(CLSID.createFromProgID("jniwrapper.comtojavasample"),
                     ClsCtx.LOCAL_SERVER);

                    IPersistImpl p = new IPersistImpl(dispatch);
                    CLSID clsid = new CLSID();
                    p.getClassID(clsid);
                    System.out.println("ClassID = " + clsid);

                    Variant result = new Variant();
                    Automation automation = new Automation(dispatch);

                    result = automation.invoke("getProgId");
                    System.out.println("PROG_ID = " + result.getValue());

                 }
            };
            OleMessageLoop.invokeAndWait(runnable);
            OleMessageLoop.stop();
        }
    }
For the full code sample, please see `ComToJava/src/JavaComClientSample.java` ### 6.3.2. C++ Client You can use the `CoCreateInstance` function to create an instance of the COM server via its CLSID. If you are going to interact with the Java COM server via a standard interface, specify its `IID` in the `CoCreateInstance` function call; otherwise you should specify the `IID_Dispatch` constant. As a result, you will be able to work with the created object via the specified interface. To call methods from custom interfaces, you need to call the `IDispatch.Invoke()` method. The first parameter for the `Invoke()` method is `dispid` of the called function that was obtained using the `GetIDsOfNames()` method. Here is an extract from the sample:
    int _tmain(int argc, _TCHAR* argv[])
    {

    using namespace std;
    HRESULT  hr;

    //Initialize COM.
    CoInitialize(NULL );

    LPCOLESTR progID =  OLESTR("jniwrapper.comtojavasample");
    LPCLSID clsID = new CLSID;
    CLSIDFromProgID(progID , clsID);

    //Working with Java COM Server via the IPersist interface
    IPersist* iPersistInst;
    hr = CoCreateInstance(*clsID,
                               NULL,
                               CLSCTX_LOCAL_SERVER,
                               IID_IPersist,
                               (void **)&iPersistInst);

    CLSID resultClsID;
    iPersistInst->GetClassID(&resultClsID);
    LPOLESTR  stringClsID;
    hr = StringFromCLSID(resultClsID , &stringClsID);
    wprintf(L"GetClassID = %s%s", (wchar_t*)stringClsID, "\n");

    //Working with Java COM Server via the IDispatch interface
    IDispatch* iDispatchInst;
    hr = CoCreateInstance(*clsID,
                               NULL,
                               CLSCTX_LOCAL_SERVER,
                               IID_IDispatch,
                               (void **)&iDispatchInst);

    DISPID dispid;
    VARIANT result;
    OLECHAR* funcName;
    DISPPARAMS dispparamsNoArgs = {NULL, NULL, 0, 0,};

    //Calling the "getProgID" method
    funcName = L"getProgId";
    iDispatchInst->GetIDsOfNames(IID_NULL,&funcName,1,GetUserDefaultLCID(),&dispid);
    iDispatchInst->Invoke(dispid,
          IID_NULL,
          GetUserDefaultLCID(),
          DISPATCH_METHOD,
          &dispparamsNoArgs,
          &result,
          NULL,
          NULL);
    wprintf(L"ProgID = %s%s", (wchar_t*)result.bstrVal, "\n");

    // Free COM resources
    CoUninitialize();
    }
For the full code sample, please see `ComToJava/native/CppSample.cpp` ### 6.3.3. Visual Basic Client The Visual Basic language uses Automation technology to create the COM server object by default. So you just need to create an `Object` variable and use the `CreateObject` function with `PROG_ID` or `CLSID` as its parameter to return the COM server object instance. As a result, you will be able to call the object's methods declared in your custom interface. In the following example, `JavaServer` is a COM server and we're calling its `getClassID` and `getProgId` methods.
    Public Class Sample

        <STAThread()> _
        Public Shared Sub Main()
            'Creating Java Com Server object by its ProgID
            Dim JavaServer As Object
            JavaServer = CreateObject("jniwrapper.comtojavasample")
            'Calling the server's methods
            Dim myClsID As Guid
            JavaServer.getClassID(myClsID)
            Console.WriteLine("ClassID = {" + myClsID.ToString + "}")
            Console.WriteLine("ProgID = " + JavaServer.getProgId)

        End Sub 'Main

    End Class
For the full code sample, please see `ComToJava/native/VBSample` # Chapter 7. ComfyJ Samples The ComfyJ distribution includes a number of samples that demonstrate different aspects of ComfyJ functionality. Among them are samples showing how to embed and interact with popular ActiveX controls such as Microsoft Office applications, Acrobat Reader, Macromedia Flash Player, QuickTime and others. Please use the ComfyJDemo application to see all these samples in action. Some of the samples require generated stubs. You can generate stubs using the Code Generator application. Follow these steps after launching the 'Code Generator for ComfyJ' application to generate the stubs: Select the Generate for a registered COM type library from the list. Select the necessary COM type library by its Description or GUID, which can be found in the java docs of the sample class. For example, if you want to try the WordIntegrationSample, you will need to choose the Microsoft Word 11.0 Object Library. Fill the Destination Folder field with any folder you wish to. Fill the Target Package Name field with the package name from the 'In the package:' line of the sample java docs. For example, if you want to try the WordIntegrationSample, you will need to fill it with word. Link up the generated sources to your project. # Chapter 8. Support If you encounter any problems or have questions regarding our product, please check the documents listed below. The answer to your question may already be there: Installation instructions Programmer's Guide Frequently Asked Questions (FAQ) page at: http://www.jniwrapper.com/pages/comfyj/faq/faq If none of the above resources contain the required information, please e-mail us at: comfyj-support@jniwrapper.com ## 8.1. ComfyJ Forum If you want to discuss topics related to COM integration, please visit a specialized forum on the JNIWrapper site: http://www.jniwrapper.com/pages/forums/forumsGroup?forumGroup=4 ## 8.2. Reporting Problems Should you experience any problem or find any bugs, please submit the issue to us using a special report form on the JNIWrapper site at the following address: http://www.jniwrapper.com/pages/support/reportForm The form will help you provide all necessary information. ## 8.3. Troubleshooting To find a solution to your problem, please visit the Troubleshooting page on our site at: http://www.jniwrapper.com/pages/jniwrapper/tshoot This page is regularly updated using information from support requests. If you don't find a solution, please e-mail us at comfyj-support@jniwrapper.com or report the problem as described in the previous section. # Chapter 9. Where to Get a New Version To obtain the latest version of ComfyJ and to receive up-to-date information, please visit: http://www.jniwrapper.com/pages/comfyj/overview
| Copyright © 2002-2005 TeamDev Ltd. |