[bug#39745] [v4 1/2] gnu: java-openjfx-build: Fix openjfx-swing component build for JDKu8

[Alexey Abramov <levenson@mmer.org>]

* gnu/packages/java.scm (java-openjfx-build)[source]: Use it.
* gnu/packages/patches/java-openjfx-build-swing-compile-JFXPanel-with-JDK-8.patch:
  New file.
* gnu/local.mk (dist_patch_DATA): Add it.
---
 gnu/local.mk                                  |  1 +
 gnu/packages/java.scm                         |  3 +-
 ...ld-swing-compile-JFXPanel-with-JDK-8.patch | 63 +++++++++++++++++++
 3 files changed, 66 insertions(+), 1 deletion(-)
 create mode 100644 gnu/packages/patches/java-openjfx-build-swing-compile-JFXPanel-with-JDK-8.patch

diff --git a/gnu/local.mk b/gnu/local.mk
index 476aa00511..010247be3b 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -1033,6 +1033,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/java-commons-collections-fix-java8.patch \
   %D%/packages/patches/java-jeromq-fix-tests.patch		\
   %D%/packages/patches/java-openjfx-build-get_guix_jdk_version.patch    \
+  %D%/packages/patches/java-openjfx-build-swing-compile-JFXPanel-with-JDK-8.patch     \
   %D%/packages/patches/java-powermock-fix-java-files.patch		\
   %D%/packages/patches/java-simple-xml-fix-tests.patch		\
   %D%/packages/patches/java-svg-salamander-Fix-non-det.patch	\
diff --git a/gnu/packages/java.scm b/gnu/packages/java.scm
index 6c1c2dba6c..768fbf09a1 100644
--- a/gnu/packages/java.scm
+++ b/gnu/packages/java.scm
@@ -2363,7 +2363,8 @@ new Date();"))
               (sha256
                (base32
                 "0yg38mwpivswccv9n96k06x3iv82i4px1a9xg9l8dswzwmfj259f"))
-              (patches (search-patches "java-openjfx-build-get_guix_jdk_version.patch"))))
+              (patches (search-patches "java-openjfx-build-get_guix_jdk_version.patch"
+                                       "java-openjfx-build-swing-compile-JFXPanel-with-JDK-8.patch"))))
     (build-system ant-build-system)
     (arguments
      `(#:jar-name "java-openjfx.jar"
diff --git a/gnu/packages/patches/java-openjfx-build-swing-compile-JFXPanel-with-JDK-8.patch b/gnu/packages/patches/java-openjfx-build-swing-compile-JFXPanel-with-JDK-8.patch
new file mode 100644
index 0000000000..363ce9509b
--- /dev/null
+++ b/gnu/packages/patches/java-openjfx-build-swing-compile-JFXPanel-with-JDK-8.patch
@@ -0,0 +1,63 @@
+From 173e65937d9e76872df51f7ba39c9d58986dc38f Mon Sep 17 00:00:00 2001
+From: Alexey Abramov <levenson@mmer.org>
+Date: Fri, 3 Jan 2020 01:17:45 +0100
+Subject: [PATCH] java-openjfx-build: Cannot compile JFXPanel with JDK 8
+
+In JDKu9 getDefaultScale method was removed and sun.java2d.SurfaceData class now
+has separate getDefaultScaleX() and getDefaultScaleY() methods. See
+https://bugs.openjdk.java.net/browse/JDK-8073320 for more info.
+
+Backport the missing port to build openjfx-swing package using JDKu8. For more
+info please see https://bugs.openjdk.java.net/browse/JDK-8149967
+
+---
+ .../java/javafx/embed/swing/JFXPanel.java     | 20 ++++++++++++++++++-
+ 1 file changed, 19 insertions(+), 1 deletion(-)
+
+diff --git a/modules/swing/src/main/java/javafx/embed/swing/JFXPanel.java b/modules/swing/src/main/java/javafx/embed/swing/JFXPanel.java
+index 97515e2290..614ed656b9 100644
+--- a/modules/swing/src/main/java/javafx/embed/swing/JFXPanel.java
++++ b/modules/swing/src/main/java/javafx/embed/swing/JFXPanel.java
+@@ -81,6 +81,7 @@ import sun.awt.AppContext;
+ import sun.awt.CausedFocusEvent;
+ import sun.awt.SunToolkit;
+ import sun.java2d.SunGraphics2D;
++import sun.java2d.SurfaceData;
+ import sun.util.logging.PlatformLogger;
+ import sun.util.logging.PlatformLogger.Level;
+
+@@ -681,6 +682,23 @@
+                 e.getCaret().getInsertionIndex());
+     }
+
++    // FIXME: once we move to JDK 9 as the boot JDK we should remove the
++    // reflection code from this method, consider changing it to
++    // use double rather than int, and account for the possibility of
++    // a different scale factor in X and Y.
++    private int getDefaultScale(SurfaceData surfaceData) {
++        /*
++          double scale = surfaceData.getDefaultScaleX();
++        */
++        double scale = 1;
++        try {
++            Method meth = SurfaceData.class.getMethod("getDefaultScaleX");
++            scale = (Double)meth.invoke(surfaceData);
++        } catch (Exception ex) {
++        }
++
++        return (int)Math.round(scale);
++    }
+
+     /**
+      * Overrides the {@link javax.swing.JComponent#paintComponent(Graphics)}
+@@ -720,7 +738,7 @@ public class JFXPanel extends JComponent {
+
+             int newScaleFactor = scaleFactor;
+             if (g instanceof SunGraphics2D) {
+-                newScaleFactor = ((SunGraphics2D)g).surfaceData.getDefaultScale();
++                newScaleFactor = getDefaultScale(((SunGraphics2D)g).surfaceData);
+             }
+             if (scaleFactor != newScaleFactor) {
+                 resizePixelBuffer(newScaleFactor);
+--
+2.24.1
--
2.24.1