--- jffi-jffi-1.2.12/build.xml	2016-04-29 23:23:51.000000000 +0200
+++ jffi-jffi-1.2.12/build.xml	2019-04-03 20:08:43.577425168 +0200
@@ -151,9 +151,10 @@
   <target name="-post-jar" depends="-assemble-final-jar"/>
 
   <target name="-do-compile" depends="-init">
+    <mkdir dir="${build.native.dir}"/>
     <mkdir dir="${build.classes.dir}"/>
     <!-- Compile the java code from ${src} into ${build} -->
-    <javac srcdir="${src.dir}" destdir="${build.classes.dir}" includeantruntime="false"/>
+    <javac srcdir="${src.dir}" destdir="${build.classes.dir}" nativeheaderdir="${build.native.dir}" includeantruntime="false"/>
   </target>
 
   <target name="-compile-java" depends="-do-compile"/>
@@ -282,26 +283,10 @@
 
 
   <target name="-generate-version" depends="-init,-init-vars,-generate-version-source">
-    <javac target="1.6" destdir="${build.classes.dir}" srcdir="${build.dir}/java" includeantruntime="false"/>
+    <javac target="1.6" destdir="${build.classes.dir}" srcdir="${build.dir}/java"  nativeheaderdir="${build.native.dir}" includeantruntime="false"/>
   </target>
 
-  <target name="-generate-native-headers" depends="-init-vars,-generate-version,-compile-java">
-    <mkdir dir="${build.native.dir}"/>
-    <mkdir dir="${build.classes.dir}"/>
-    <javah classpath="${build.classes.dir}" destdir="${build.native.dir}" force="yes">
-      <class name="com.kenai.jffi.Foreign"/>
-      <class name="com.kenai.jffi.ObjectBuffer"/>
-      <class name="com.kenai.jffi.Version"/>
-    </javah>
-    <!--
-    <exec executable="javah" failonerror="true">
-      <arg line="-d ${build.native.dir}"/>
-      <arg line="-classpath ${build.classes.dir}"/>
-      <arg line="com.kenai.jffi.Foreign"/>
-      <arg line="com.kenai.jffi.ObjectBuffer"/>
-    </exec>
-    -->
-  </target>
+  <target name="-generate-native-headers" depends="-init-vars,-generate-version,-compile-java" />
 
   <target name="-build-native-library" depends="-init-vars, -generate-native-headers, -generate-version">
     <mkdir dir="${build.native.dir}"/>
--- jffi-jffi-1.2.12/src/main/java/com/kenai/jffi/ObjectBuffer.java	2016-04-29 23:23:51.000000000 +0200
+++ jffi-jffi-1.2.12/src/main/java/com/kenai/jffi/ObjectBuffer.java	2019-04-03 20:00:13.598956759 +0200
@@ -32,55 +32,57 @@
 
 package com.kenai.jffi;
 
+import java.lang.annotation.Native;
+
 /**
  * Holds objects the native code must handle - such as primitive arrays
  */
 final class ObjectBuffer {
     /** Copy the array contents to native memory before calling the function */
-    public static final int IN = 0x1;
+    @Native public static final int IN = 0x1;
 
     /** After calling the function, reload the array contents from native memory */
-    public static final int OUT = 0x2;
+    @Native public static final int OUT = 0x2;
 
     /** Append a NUL byte to the array contents after copying to native memory */
-    public static final int ZERO_TERMINATE = 0x4;
+    @Native public static final int ZERO_TERMINATE = 0x4;
 
     /** Pin the array memory and pass the JVM memory pointer directly to the function */
-    public static final int PINNED = 0x8;
+    @Native public static final int PINNED = 0x8;
 
     /** For OUT arrays, clear the temporary native memory area */
-    public static final int CLEAR = 0x10;
+    @Native public static final int CLEAR = 0x10;
 
     /*
      * WARNING: The following flags cannot be altered without recompiling the native code 
      */
-    static final int INDEX_SHIFT = 16;
-    static final int INDEX_MASK = 0x00ff0000;
-    static final int TYPE_SHIFT = 24;
-    static final int TYPE_MASK = 0xff << TYPE_SHIFT;
-    static final int PRIM_MASK = 0x0f << TYPE_SHIFT;
-    static final int FLAGS_SHIFT = 0;
-    static final int FLAGS_MASK = 0xff;
-
-    static final int ARRAY = 0x10 << TYPE_SHIFT;
-    static final int BUFFER = 0x20 << TYPE_SHIFT;
-    static final int JNI = 0x40 << TYPE_SHIFT;
-    
-    static final int BYTE = 0x1 << TYPE_SHIFT;
-    static final int SHORT = 0x2 << TYPE_SHIFT;
-    static final int INT = 0x3 << TYPE_SHIFT;
-    static final int LONG = 0x4 << TYPE_SHIFT;
-    static final int FLOAT = 0x5 << TYPE_SHIFT;
-    static final int DOUBLE = 0x6 << TYPE_SHIFT;
-    static final int BOOLEAN = 0x7 << TYPE_SHIFT;
-    static final int CHAR = 0x8 << TYPE_SHIFT;
+    @Native static final int INDEX_SHIFT = 16;
+    @Native static final int INDEX_MASK = 0x00ff0000;
+    @Native static final int TYPE_SHIFT = 24;
+    @Native static final int TYPE_MASK = 0xff << TYPE_SHIFT;
+    @Native static final int PRIM_MASK = 0x0f << TYPE_SHIFT;
+    @Native static final int FLAGS_SHIFT = 0;
+    @Native static final int FLAGS_MASK = 0xff;
+
+    @Native static final int ARRAY = 0x10 << TYPE_SHIFT;
+    @Native static final int BUFFER = 0x20 << TYPE_SHIFT;
+    @Native static final int JNI = 0x40 << TYPE_SHIFT;
+    
+    @Native static final int BYTE = 0x1 << TYPE_SHIFT;
+    @Native static final int SHORT = 0x2 << TYPE_SHIFT;
+    @Native static final int INT = 0x3 << TYPE_SHIFT;
+    @Native static final int LONG = 0x4 << TYPE_SHIFT;
+    @Native static final int FLOAT = 0x5 << TYPE_SHIFT;
+    @Native static final int DOUBLE = 0x6 << TYPE_SHIFT;
+    @Native static final int BOOLEAN = 0x7 << TYPE_SHIFT;
+    @Native static final int CHAR = 0x8 << TYPE_SHIFT;
 
     /* NOTE: The JNI types can overlap the primitive type, since they are mutually exclusive */
     /** The JNIEnv address */
-    public static final int JNIENV = 0x1 << TYPE_SHIFT;
+    @Native public static final int JNIENV = 0x1 << TYPE_SHIFT;
 
     /** The jobject handle */
-    public static final int JNIOBJECT = 0x2 << TYPE_SHIFT;
+    @Native public static final int JNIOBJECT = 0x2 << TYPE_SHIFT;
 
     /** The objects stored in this buffer */
     private Object[] objects;
--- jffi-jffi-1.2.12/version.xml	2016-04-29 23:23:51.000000000 +0200
+++ jffi-jffi-1.2.12/version.xml	2019-04-03 20:04:11.168106751 +0200
@@ -8,11 +8,12 @@
         <mkdir dir="${build.dir}/java/com/kenai/jffi"/>
         <echo file="${build.dir}/java/com/kenai/jffi/Version.java" append="false">
             package com.kenai.jffi;
+            import java.lang.annotation.Native;
             public final class Version {
                 private Version() {}
-                public static final int MAJOR = ${jffi.version.major};
-                public static final int MINOR = ${jffi.version.minor};
-                public static final int MICRO = ${jffi.version.micro};
+                @Native public static final int MAJOR = ${jffi.version.major};
+                @Native public static final int MINOR = ${jffi.version.minor};
+                @Native public static final int MICRO = ${jffi.version.micro};
             }
         </echo>
     </target>