Modifier Z Order Windows avec JNA

package zOrder;

import java.awt.AWTException;
import java.awt.Image;
import java.awt.MenuItem;
import java.awt.PopupMenu;
import java.awt.Rectangle;
import java.awt.SystemTray;
import java.awt.Toolkit;
import java.awt.TrayIcon;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import javax.swing.JOptionPane;
import javax.swing.SwingUtilities;

import com.sun.jna.Native;
import com.sun.jna.Pointer;
import com.sun.jna.Structure;
import com.sun.jna.platform.win32.WinDef.BOOL;
import com.sun.jna.platform.win32.WinDef.HWND;
import com.sun.jna.platform.win32.WinDef.POINT;
import com.sun.jna.platform.win32.WinDef.RECT;
import com.sun.jna.platform.win32.WinUser;
import com.sun.jna.platform.win32.WinUser.WNDENUMPROC;
import com.sun.jna.win32.StdCallLibrary;
import com.sun.jna.win32.W32APIOptions;

final class ZOrder {
 private static final ArrayList<HWND>HANDLES = new ArrayList<HWND>();
 private static int windowsSize;
 private static class ZOrderInverter {
  private static TrayIcon tray;
  private static PopupMenu popup = new PopupMenu();
  static {
   MenuItem _close = new MenuItem("Close");
   _close.addActionListener(new ActionListener(){
    public void actionPerformed(ActionEvent e) {
     SystemTray.getSystemTray().remove(ZOrderInverter.tray);
    }
   });
   popup.add(_close);
   if(SystemTray.isSupported() == true) {
    Image _icon = Toolkit.getDefaultToolkit().getImage (
     ZOrder.class.getResource("/rsrc/Z Order Inverter TrayIcon.png")
    );
    tray = new TrayIcon(_icon, "Z Order Inverter is running", popup);
    tray.setImageAutoSize(true);
    try {
     SystemTray.getSystemTray().add(ZOrderInverter.tray);
    } catch(AWTException e) {
     e.printStackTrace();
    }
   }
  }
  private static boolean isActive(){
   List<TrayIcon>trays_list = Arrays.asList(SystemTray.getSystemTray().getTrayIcons());
   return trays_list.contains(tray);
  }
 }
 private static class Window {
  private String name;
  private Window(String _name, Rectangle _bounds) {
   name = _name;
  }
 }
 private interface User32 extends StdCallLibrary {
  static final User32 INSTANCE = (User32)Native.load (
   "user32", User32.class, W32APIOptions.DEFAULT_OPTIONS
  );
  class WINDOWPLACEMENT extends Structure {
   public int length;
   public int flags;
   public int showCmd;
   public POINT ptMinPosition;
   public POINT ptMaxPosition;
   public RECT rcNormalPosition;
   private WINDOWPLACEMENT(){
    length = size();
    
    // Lignes totalement inutiles, juste pour ne pas avoir de @SuppressWarnings("unused")
    List<Object>_null = Arrays.asList (
     length, flags, showCmd, ptMinPosition, ptMaxPosition, rcNormalPosition
    );
    _null.isEmpty();
   }
   @Override
   protected List<String>getFieldOrder(){
    return Arrays.asList (
     "length", "flags", "showCmd", "ptMinPosition", "ptMaxPosition", "rcNormalPosition"
    );
   }
  }
  int GetWindowRect(HWND h_wnd, int _rect[]);
  int GetWindowTextA(HWND h_wnd, byte lp_string[], int n_max_count);
  boolean EnumWindows(WNDENUMPROC lp_enum_func, Pointer _pointer);
  boolean IsWindowVisible(HWND h_wnd);
  BOOL GetWindowPlacement(HWND h_wnd, WINDOWPLACEMENT lp_wnd_pl);
  BOOL SetWindowPos (
   HWND h_wnd, HWND h_wnd_insert_after, int _x, int _y, int _cx, int _cy, int u_flag
  );
 }
 private static ArrayList<Window>getWindows()  {
  HANDLES.clear();
  ArrayList<Window>_windows = new ArrayList<Window>();
  User32.INSTANCE.EnumWindows(new WNDENUMPROC(){
   @Override
   public boolean callback(HWND h_wnd, Pointer _pointer) {
    if(getWindow(h_wnd).name.isEmpty() == false) {
     HANDLES.add(h_wnd);
     _windows.add(new Window(getWindowName(h_wnd), getWindowBounds(h_wnd)));
    }
    return true;
   }
  }, null);
  for(int i = _windows.size() - 1; i >= 0; i--) {
   User32.WINDOWPLACEMENT _place = new User32.WINDOWPLACEMENT();
   User32.INSTANCE.GetWindowPlacement(HANDLES.get(i), _place);
   if(User32.INSTANCE.IsWindowVisible(HANDLES.get(i)) == false) {
    _windows.remove(i);
    HANDLES.remove(i);
   } else switch(_place.showCmd) {
   case 2:
    _windows.remove(i);
    HANDLES.remove(i);
    break;
   default:
    switch(_windows.get(i).name) {
    case "":
    case "Program Manager":
    case "Microsoft Text Input Application":
     _windows.remove(i);
     HANDLES.remove(i);
    }
    break;
   }
  }
  return _windows;
 }
 private static String getWindowName(HWND h_wnd) {
  byte window_text[] = new byte[512];
  User32.INSTANCE.GetWindowTextA(h_wnd, window_text, 512);
  return Native.toString(window_text);
 }
 private static Window getWindow(HWND h_wnd) {
  return new Window(getWindowName(h_wnd), getWindowBounds(h_wnd));
 }
 private static Rectangle getWindowBounds(HWND h_wnd) {
  int _rect[] = { 0, 0, 0, 0 };
  switch(User32.INSTANCE.GetWindowRect(h_wnd, _rect)) {
  case 0:
   return null;
  }
  return new Rectangle(_rect[0], _rect[1], _rect[2], _rect[3]);
 }
 public static void main(String _args[]) {
  SwingUtilities.invokeLater(new Runnable(){
   @Override
   public void run(){
    new ZOrderInverter();
   }
  });
  ArrayList<Window>_windows = getWindows();
  String _title = _windows.get(0).name;
  windowsSize = _windows.size();
  while(ZOrderInverter.isActive() == true) {
   switch(_windows.size()) {
   case 0:
    break;
   default:
    switch(_title.compareTo(_windows.get(0).name)) {
    case 0:
     break;
    default:
     _title = _windows.get(0).name;
     if(windowsSize < _windows.size()) {
      User32.INSTANCE.SetWindowPos (
       HANDLES.get(0)
       , HANDLES.get(HANDLES.size() - 1)
       , 0, 0, 0, 0
       , WinUser.SWP_NOMOVE | WinUser.SWP_NOSIZE
      );
      _title = _windows.get(1).name;
     }
     windowsSize = _windows.size();
     break;
    }
    break;
   }
   _windows = getWindows();
  }
  SwingUtilities.invokeLater(new Runnable(){
   @Override
   public void run(){
    JOptionPane.showMessageDialog (
     null
     , "Z Order Inverter is no more active and will close."
     , "Z Order Inverter"
     , JOptionPane.INFORMATION_MESSAGE
    );
   }
  });
 }
}