使用javax.accessibility与来自另一个JVM的应用程序交互

Question

我正在尝试使用java辅助功能实用程序与一个java swing应用程序交互。java可访问性指南指出

要使辅助技术与Java应用程序一起工作，将其加载到与其提供访问的Java应用程序相同的JVM中。这是通过使用assistive_technologies属性完成的。

和

Monkey类位于此版本的Java辅助工具附带的示例/Monkey目录中。在运行它之前，需要按照以下说明适当地设置您的环境： 将jaccess.jar和jaccess-examples.jar复制到JDKHOME/jre/lib/ext目录下的JDK1.2或更高版本的安装中。修改$JDKHOME/jre/lib/create sibility.properties文件(如果不存在的话创建一个)，以包含以下行: assistive_technologies=Monkey 按照上面的说明，任何时候启动Java应用程序时都会自动启动Monkey。例如，您可以运行作为Swing演示应用程序的一部分的SwingSet演示。

我已经将jaccess-examples.jar复制到我的jre文件夹(C：\ProgramFiles\Java\jre1.8.0_221\lib\ext)中，jaccess.jar已经在那里，添加到了(C：\ProgramFiles\Java\jre1.8.0_221\lib)行assistive_technologies=Monkey中的accessibility.properties文件中，但是在启动launching应用程序时什么也不会发生。我怎么才能让它起作用？

要注意的是，如果Monkey在与它需要访问的应用程序相同的JVM中启动，即使不修改accessibility.properties文件，它实际上也能工作。

Answer 1

//load WindowsAccessBridge-64.dll

    import com.sun.jna.Library;
    import com.sun.jna.Native;
    import com.sun.jna.Pointer;
    import com.sun.jna.platform.win32.WinDef;
    import com.sun.jna.ptr.PointerByReference;

    public interface WindowsAccessBridge extends Library {

        //Load the .dll using JNA
        WindowsAccessBridge INSTANCE = Native.load("windowsaccessbridge-64", WindowsAccessBridge.class);


        //declare some functions from the .dll

        void Windows_run();

        boolean isJavaWindow(WinDef.HWND window);

        boolean getAccessibleContextFromHWND(WinDef.HWND target, WinDef.LONGByReference vmID, PointerByReference accessibleContext);

        boolean getAccessibleContextInfo(WinDef.LONG vmID, Pointer accessibleContext, ABPackages.AccessibleContextInfo.ByReference info);

    }



 //load custom user32.dll, the user32 provided by JNA does not have the ChangeWindowMessageFilter function

    import com.sun.jna.Native;
    import com.sun.jna.Pointer;
    import com.sun.jna.platform.win32.WinUser.WNDENUMPROC;
    import com.sun.jna.ptr.PointerByReference;
    import com.sun.jna.win32.StdCallLibrary;
    import com.sun.jna.platform.win32.WinDef.HWND;

    public interface UUser32 extends StdCallLibrary {

        UUser32 INSTANCE = Native.load("user32", UUser32.class);

        boolean ChangeWindowMessageFilter(int message, int flag);

    }

    //to get window messages you need a message pump
    import com.sun.jna.platform.win32.User32;
    import com.sun.jna.platform.win32.WinUser;
    import static com.sun.jna.platform.win32.WinUser.WM_COPYDATA;
    import static com.sun.jna.platform.win32.WinUser.WM_USER;

    public class WindowMessagePump extends Thread {
        //get a WAB instance
        private final WindowsAccessBridge wab = WindowsAccessBridge.INSTANCE;
        //get a custom user32 instance
        private final UUser32 uUser32 = UUser32.INSTANCE;
        // the user32 provided by JNA
        private final User32 user32 = User32.INSTANCE;

        @Override
        public void run() {
            uUser32.ChangeWindowMessageFilter(WM_COPYDATA, 1);
            for (int i = WM_USER + 1; i < 0xfff; i++) {
                uUser32.ChangeWindowMessageFilter(i, 1);
            }
            wab.Windows_run();
            WinUser.MSG msg = new WinUser.MSG();
            while (user32.GetMessage(msg, null, 0, 0) > 0) {
                user32.TranslateMessage(msg);
                user32.DispatchMessage(msg);
            }
        }
    }

    //you also need some structures to get the needed information 

    import com.sun.jna.Structure;

    public class ABPackages {

        static final int MAX_STRING_SIZE = 1024;
        static final int SHORT_STRING_SIZE = 256;

        @Structure.FieldOrder({"name", "description", "role", "role_en_US", "states", "states_en_US", "indexInParent",
                "childrenCount", "x", "y", "width", "height", "accessibleComponent", "accessibleAction",
                "accessibleSelection", "accessibleText", "accessibleInterfaces"})
        public static class AccessibleContextInfo extends Structure {
            public char[] name = new char[MAX_STRING_SIZE];        // the AccessibleName of the object
            public char[] description = new char[MAX_STRING_SIZE]; // the AccessibleDescription of the object
            public char[] role = new char[SHORT_STRING_SIZE];      // localized AccesibleRole string
            public char[] role_en_US = new char[SHORT_STRING_SIZE];
            public char[] states = new char[SHORT_STRING_SIZE];    // localized AccesibleStateSet string (comma separated)
            public char[] states_en_US = new char[SHORT_STRING_SIZE];
            public int indexInParent;                   // index of object in parent
            public int childrenCount;                  // # of children, if any
            public int x;                              // screen x-axis co-ordinate in pixels
            public int y;                              // screen y-axis co-ordinate in pixels
            public int width;                          // pixel width of object
            public int height;                         // pixel height of object
            public int accessibleComponent;            // flags for various additional
            public int accessibleAction;               // Java Accessibility interfaces
            public int accessibleSelection;            // FALSE if this object doesn't
            public int accessibleText;                 // implement the additional interface
            public int accessibleInterfaces;           // new bitfield containing additional interface flags

            public static class ByReference extends AccessibleContextInfo implements Structure.ByReference {
            }

            public static class ByValue extends AccessibleContextInfo implements Structure.ByValue {
            }
        }
    }


    //and now for the implementation
    import com.sun.jna.Native;
    import com.sun.jna.Pointer;
    import com.sun.jna.platform.DesktopWindow;
    import com.sun.jna.platform.WindowUtils;
    import com.sun.jna.platform.win32.WinDef;
    import com.sun.jna.ptr.PointerByReference;

    public static void main(String[] args) throws InterruptedException {
        //start the message pump
        WindowMessagePump messagePump = new WindowMessagePump();
        messagePump.setDaemon(true);
        messagePump.start();
        //wait a few seconds for the pump to start just in case
        Thread.sleep(2000);

        //get an instance of windows access bridge
        WindowsAccessBridge accessBridge = WindowsAccessBridge.INSTANCE;

        //get a list of active windows
        List<DesktopWindow> list = WindowUtils.getAllWindows(true);

        for (DesktopWindow window : list) {
            if (window.getFilePath().contains("the name of the window you are looking for")) {
                WinDef.HWND handle = window.getHWND();
                //check if its a java window
                if (accessBridge.isJavaWindow(handle)) {

                    WinDef.LONGByReference vmID = new WinDef.LONGByReference();
                    PointerByReference accessibleContext = new PointerByReference();

                    boolean getAccessibleContextSuccess = accessBridge.getAccessibleContextFromHWND(handle, vmID, accessibleContext);

                    if(getAccessibleContextSuccess) {
                        ABPackages.AccessibleContextInfo.ByReference contextInfo = new ABPackages.AccessibleContextInfo.ByReference();
                        boolean getContextInfoSuccess = accessBridge.getAccessibleContextInfo(vmID.getValue(), accessibleContext.getValue(), contextInfo);
                        System.out.println("getContextInfoSuccess: " + getContextInfoSuccess);
                    }
                    break;
                }
            }
        }
    }