Merge branch 4.x

modules/java/generator/src/cpp/CleanableMat.cpp

@@ -0,0 +1,28 @@
+// This file is part of OpenCV project.
+// It is subject to the license terms in the LICENSE file found in the top-level directory
+// of this distribution and at http://opencv.org/license.html
+
+#include "opencv2/core.hpp"
+
+#define LOG_TAG "org.opencv.core.CleanableMat"
+#include "common.h"
+#include <iostream>
+
+using namespace cv;
+
+extern "C" {
+    //
+    //  native support for java finalize() or cleaners
+    //  static void CleanableMat::n_delete( __int64 self )
+    //
+
+    JNIEXPORT void JNICALL Java_org_opencv_core_CleanableMat_n_1delete
+    (JNIEnv*, jclass, jlong self);
+
+    JNIEXPORT void JNICALL Java_org_opencv_core_CleanableMat_n_1delete
+    (JNIEnv*, jclass, jlong self)
+    {
+        // LOGD("CleanableMat.n_delete() called\n");
+        delete (Mat*) self;
+    }
+}

modules/java/generator/src/cpp/Mat.cpp

@@ -2114,22 +2114,6 @@ JNIEXPORT jlong JNICALL Java_org_opencv_core_Mat_n_1zeros__I_3II
     return 0;
 }
 
-
-
-//
-//  native support for java finalize()
-//  static void Mat::n_delete( __int64 self )
-//
-
-JNIEXPORT void JNICALL Java_org_opencv_core_Mat_n_1delete
-  (JNIEnv*, jclass, jlong self);
-
-JNIEXPORT void JNICALL Java_org_opencv_core_Mat_n_1delete
-  (JNIEnv*, jclass, jlong self)
-{
-    delete (Mat*) self;
-}
-
 } // extern "C"
 
 namespace {

modules/java/generator/src/java9/CleanableMat.java

@@ -0,0 +1,23 @@
+package org.opencv.core;
+
+import java.lang.ref.Cleaner;
+
+public abstract class CleanableMat {
+    // A native memory cleaner for the OpenCV library
+    public static Cleaner cleaner = Cleaner.create();
+
+    protected CleanableMat(long obj) {
+        if (obj == 0)
+            throw new UnsupportedOperationException("Native object address is NULL");
+
+        nativeObj = obj;
+
+        // The n_delete action must not refer to the object being registered. So, do not use nativeObj directly.
+        long nativeObjCopy = nativeObj;
+        cleaner.register(this, () -> n_delete(nativeObjCopy));
+    }
+
+    private static native void n_delete(long nativeObj);
+
+    public final long nativeObj;
+}

modules/java/generator/src/java_classic/CleanableMat.java

@@ -0,0 +1,21 @@
+package org.opencv.core;
+
+public abstract class CleanableMat {
+
+    protected CleanableMat(long obj) {
+        if (obj == 0)
+            throw new UnsupportedOperationException("Native object address is NULL");
+
+        nativeObj = obj;
+    }
+
+    @Override
+    protected void finalize() throws Throwable {
+        n_delete(nativeObj);
+        super.finalize();
+    }
+
+    private static native void n_delete(long nativeObj);
+
+    public final long nativeObj;
+}