From 8d1f254dcc2b4f413b1a610ec77b92896702cfca Mon Sep 17 00:00:00 2001
From: Alexander Alekhin <alexander.alekhin@intel.com>
Date: Fri, 2 Jul 2021 10:41:41 +0000
Subject: [PATCH] java: force using of 'Ptr<>' for OpenCV classes

backport of commit: e5841d3126527ff1151ab480ba8e291e29942e07
---
 modules/dnn/misc/java/gen_dict.json |  2 +-
 modules/java/generator/gen_java.py  | 35 ++++++++++++++++-------------
 2 files changed, 21 insertions(+), 16 deletions(-)

diff --git a/modules/dnn/misc/java/gen_dict.json b/modules/dnn/misc/java/gen_dict.json
index 5a397eac51..65ecfdc25e 100644
--- a/modules/dnn/misc/java/gen_dict.json
+++ b/modules/dnn/misc/java/gen_dict.json
@@ -54,7 +54,7 @@
                 ]
 
             ],
-            "jni_name": "(*(cv::dnn::DictValue*)%(n)s_nativeObj)",
+            "jni_name": "(*(*(Ptr<cv::dnn::DictValue>*)%(n)s_nativeObj))",
             "jni_type": "jlong",
             "suffix": "J",
             "j_import": "org.opencv.dnn.DictValue"
diff --git a/modules/java/generator/gen_java.py b/modules/java/generator/gen_java.py
index 8e5c69e788..f3b5e132d1 100755
--- a/modules/java/generator/gen_java.py
+++ b/modules/java/generator/gen_java.py
@@ -224,6 +224,9 @@ class ClassInfo(GeneralInfo):
         for m in decl[2]:
             if m.startswith("="):
                 self.jname = m[1:]
+            if m == '/Simple':
+                self.smart = False
+
         self.base = ''
         if decl[1]:
             #self.base = re.sub(r"\b"+self.jname+r"\b", "", decl[1].replace(":", "")).strip()
@@ -370,7 +373,7 @@ class JavaWrapperGenerator(object):
 
     def clear(self):
         self.namespaces = ["cv"]
-        self.classes = { "Mat" : ClassInfo([ 'class Mat', '', [], [] ], self.namespaces) }
+        self.classes = { "Mat" : ClassInfo([ 'class Mat', '', ['/Simple'], [] ], self.namespaces) }
         self.module = ""
         self.Module = ""
         self.ported_func_list = []
@@ -390,10 +393,15 @@ class JavaWrapperGenerator(object):
         if name in type_dict and not classinfo.base:
             logging.warning('duplicated: %s', classinfo)
             return
+        if self.isSmartClass(classinfo):
+            jni_name = "*((*(Ptr<"+classinfo.fullName(isCPP=True)+">*)%(n)s_nativeObj).get())"
+        else:
+            jni_name = "(*("+classinfo.fullName(isCPP=True)+"*)%(n)s_nativeObj)"
         type_dict.setdefault(name, {}).update(
             { "j_type" : classinfo.jname,
               "jn_type" : "long", "jn_args" : (("__int64", ".nativeObj"),),
-              "jni_name" : "(*("+classinfo.fullName(isCPP=True)+"*)%(n)s_nativeObj)", "jni_type" : "jlong",
+              "jni_name" : jni_name,
+              "jni_type" : "jlong",
               "suffix" : "J",
               "j_import" : "org.opencv.%s.%s" % (self.module, classinfo.jname)
             }
@@ -401,7 +409,8 @@ class JavaWrapperGenerator(object):
         type_dict.setdefault(name+'*', {}).update(
             { "j_type" : classinfo.jname,
               "jn_type" : "long", "jn_args" : (("__int64", ".nativeObj"),),
-              "jni_name" : "("+classinfo.fullName(isCPP=True)+"*)%(n)s_nativeObj", "jni_type" : "jlong",
+              "jni_name" : "&("+jni_name+")",
+              "jni_type" : "jlong",
               "suffix" : "J",
               "j_import" : "org.opencv.%s.%s" % (self.module, classinfo.jname)
             }
@@ -889,7 +898,13 @@ class JavaWrapperGenerator(object):
                 ret = "return env->NewStringUTF(_retval_.c_str());"
                 default = 'return env->NewStringUTF("");'
             elif self.isWrapped(fi.ctype): # wrapped class:
-                ret = "return (jlong) new %s(_retval_);" % self.fullTypeName(fi.ctype)
+                ret = None
+                if fi.ctype in self.classes:
+                    ret_ci = self.classes[fi.ctype]
+                    if self.isSmartClass(ret_ci):
+                        ret = "return (jlong)(new Ptr<%(ctype)s>(new %(ctype)s(_retval_)));" % { 'ctype': self.fullTypeName(fi.ctype) }
+                if ret is None:
+                    ret = "return (jlong) new %s(_retval_);" % self.fullTypeName(fi.ctype)
             elif fi.ctype.startswith('Ptr_'):
                 c_prologue.append("typedef Ptr<%s> %s;" % (self.fullTypeName(fi.ctype[4:]), fi.ctype))
                 ret = "return (jlong)(new %(ctype)s(_retval_));" % { 'ctype':fi.ctype }
@@ -1128,17 +1143,7 @@ JNIEXPORT void JNICALL Java_org_opencv_%(module)s_%(j_cls)s_delete
         if ci.smart != None:
             return ci.smart
 
-        # if parents are smart (we hope) then children are!
-        # if not we believe the class is smart if it has "create" method
-        ci.smart = False
-        if ci.base or ci.name == 'Algorithm':
-            ci.smart = True
-        else:
-            for fi in ci.methods:
-                if fi.name == "create":
-                    ci.smart = True
-                    break
-
+        ci.smart = True  # smart class is not properly handled in case of base/derived classes
         return ci.smart
 
     def smartWrap(self, ci, fullname):
-- 
2.34.1