8348625: [21u, 17u] Revert JDK-8185862 to restore old java.awt.headless behavior on Windows

Reviewed-by: mbaesken
Backport-of: e1967d5124309de5276ab88d1bcf4d24f2620dab

Author: RealCLanger

src/java.desktop/windows/classes/sun/awt/PlatformGraphicsInfo.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -28,41 +28,20 @@
 import java.awt.GraphicsEnvironment;
 import java.awt.Toolkit;
 
-import sun.awt.windows.WToolkit;
-
 public class PlatformGraphicsInfo {
 
-    private static final boolean hasDisplays;
-
-    static {
-        loadAWTLibrary();
-        hasDisplays = hasDisplays0();
-    }
-
-    @SuppressWarnings("removal")
-    private static void loadAWTLibrary() {
-        java.security.AccessController.doPrivileged(
-            new java.security.PrivilegedAction<Void>() {
-                public Void run() {
-                    System.loadLibrary("awt");
-                    return null;
-                }
-            });
-    }
-
-    private static native boolean hasDisplays0();
-
     public static GraphicsEnvironment createGE() {
         return new Win32GraphicsEnvironment();
     }
 
     public static Toolkit createToolkit() {
-        return new WToolkit();
+        return new sun.awt.windows.WToolkit();
     }
 
     public static boolean getDefaultHeadlessProperty() {
-        // If we don't find usable displays, we run headless.
-        return !hasDisplays;
+        // On Windows, we assume we can always create headful apps.
+        // Here is where we can add code that would actually check.
+        return false;
     }
 
     /*

src/java.desktop/windows/classes/sun/awt/Win32GraphicsEnvironment.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -60,8 +60,7 @@ public final class Win32GraphicsEnvironment extends SunGraphicsEnvironment {
         WToolkit.loadLibraries();
         // setup flags before initializing native layer
         WindowsFlags.initFlags();
-
-        initDisplay();
+        initDisplayWrapper();
 
         // Install correct surface manager factory.
         SurfaceManagerFactory.setInstance(new WindowsSurfaceManagerFactory());
@@ -89,6 +88,14 @@ public final class Win32GraphicsEnvironment extends SunGraphicsEnvironment {
      */
     private static native void initDisplay();
 
+    private static boolean displayInitialized;      // = false;
+    public static void initDisplayWrapper() {
+        if (!displayInitialized) {
+            displayInitialized = true;
+            initDisplay();
+        }
+    }
+
     public Win32GraphicsEnvironment() {
     }
 

src/java.desktop/windows/native/libawt/windows/Devices.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2013, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -85,75 +85,60 @@
 #include "Trace.h"
 #include "D3DPipelineManager.h"
 
-typedef struct {
-    int monitorCounter;
-    int monitorLimit;
-    HMONITOR* hmpMonitors;
-} MonitorData;
 
+/* Some helper functions (from awt_MMStub.h/cpp) */
 
-// Only monitors where CreateDC does not fail are valid
-static BOOL IsValidMonitor(HMONITOR hMon)
-{
-    MONITORINFOEX mieInfo;
-    memset((void*)(&mieInfo), 0, sizeof(MONITORINFOEX));
-    mieInfo.cbSize = sizeof(MONITORINFOEX);
-    if (!::GetMonitorInfo(hMon, (LPMONITORINFOEX)(&mieInfo))) {
-        J2dTraceLn1(J2D_TRACE_INFO, "Devices::IsValidMonitor: GetMonitorInfo failed for monitor with handle %p", hMon);
-        return FALSE;
-    }
-
-    HDC hDC = CreateDC(mieInfo.szDevice, NULL, NULL, NULL);
-    if (NULL == hDC) {
-        J2dTraceLn2(J2D_TRACE_INFO, "Devices::IsValidMonitor: CreateDC failed for monitor with handle %p, device: %S", hMon, mieInfo.szDevice);
-        return FALSE;
-    }
-
-    ::DeleteDC(hDC);
-    return TRUE;
-}
+int g_nMonitorCounter;
+int g_nMonitorLimit;
+HMONITOR* g_hmpMonitors;
 
 // Callback for CountMonitors below
-static BOOL WINAPI clb_fCountMonitors(HMONITOR hMon, HDC hDC, LPRECT rRect, LPARAM lpMonitorCounter)
+BOOL WINAPI clb_fCountMonitors(HMONITOR hMon, HDC hDC, LPRECT rRect, LPARAM lP)
 {
-    if (IsValidMonitor(hMon)) {
-        (*((int *)lpMonitorCounter))++;
-    }
-
+    g_nMonitorCounter ++;
     return TRUE;
 }
 
 int WINAPI CountMonitors(void)
 {
-    int monitorCounter = 0;
-    ::EnumDisplayMonitors(NULL, NULL, clb_fCountMonitors, (LPARAM)&monitorCounter);
-    return monitorCounter;
+    g_nMonitorCounter = 0;
+    ::EnumDisplayMonitors(NULL, NULL, clb_fCountMonitors, 0L);
+    return g_nMonitorCounter;
+
 }
 
 // Callback for CollectMonitors below
-static BOOL WINAPI clb_fCollectMonitors(HMONITOR hMon, HDC hDC, LPRECT rRect, LPARAM lpMonitorData)
+BOOL WINAPI clb_fCollectMonitors(HMONITOR hMon, HDC hDC, LPRECT rRect, LPARAM lP)
 {
-    MonitorData* pMonitorData = (MonitorData *)lpMonitorData;
-    if ((pMonitorData->monitorCounter < pMonitorData->monitorLimit) && (IsValidMonitor(hMon))) {
-        pMonitorData->hmpMonitors[pMonitorData->monitorCounter] = hMon;
-        pMonitorData->monitorCounter++;
+
+    if ((g_nMonitorCounter < g_nMonitorLimit) && (NULL != g_hmpMonitors)) {
+        g_hmpMonitors[g_nMonitorCounter] = hMon;
+        g_nMonitorCounter ++;
     }
 
     return TRUE;
 }
 
-static int WINAPI CollectMonitors(HMONITOR* hmpMonitors, int nNum)
+int WINAPI CollectMonitors(HMONITOR* hmpMonitors, int nNum)
 {
+    int retCode = 0;
+
     if (NULL != hmpMonitors) {
-        MonitorData monitorData;
-        monitorData.monitorCounter = 0;
-        monitorData.monitorLimit = nNum;
-        monitorData.hmpMonitors = hmpMonitors;
-        ::EnumDisplayMonitors(NULL, NULL, clb_fCollectMonitors, (LPARAM)&monitorData);
-        return monitorData.monitorCounter;
-    } else {
-        return 0;
+
+        g_nMonitorCounter   = 0;
+        g_nMonitorLimit     = nNum;
+        g_hmpMonitors       = hmpMonitors;
+
+        ::EnumDisplayMonitors(NULL, NULL, clb_fCollectMonitors, 0L);
+
+        retCode             = g_nMonitorCounter;
+
+        g_nMonitorCounter   = 0;
+        g_nMonitorLimit     = 0;
+        g_hmpMonitors       = NULL;
+
     }
+    return retCode;
 }
 
 BOOL WINAPI MonitorBounds(HMONITOR hmMonitor, RECT* rpBounds)

src/java.desktop/windows/native/libawt/windows/Devices.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2011, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -74,6 +74,4 @@ static CriticalSection          arrayLock;
 
 BOOL WINAPI MonitorBounds (HMONITOR, RECT*);
 
-int WINAPI CountMonitors (void);
-
 #endif // _DEVICES_H_

src/java.desktop/windows/native/libawt/windows/awt_PlatformGraphicsInfo.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -33,6 +33,7 @@
 /**
  * @test
  * @bug 8189604 8208702
+ * @requires !vm.debug | os.family != "windows"
  * @run main/othervm -Djava.awt.headless=false HangDuringStaticInitialization
  * @run main/othervm -Djava.awt.headless=true HangDuringStaticInitialization
  */