Merge pull request #4018 from Akhil-Chaturvedi:patch-1

[Saliency] Enable Java/Android bindings by adding 'WRAP java' to CMake #4018

Fixes #4016

This addresses the inability to use the `saliency` module in Android (Java/Kotlin) applications. When generated using `build_sdk.py`, the native library compiles, but the Java wrapper class (`org.opencv.saliency.Saliency`) is not generated.

# Technical Fix:
The `ocv_define_module` macro in `modules/saliency/CMakeLists.txt` was missing the `java` flag in its `WRAP` parameter.

**Change in `modules/saliency/CMakeLists.txt`:**

**OLD**
ocv_define_module(saliency opencv_imgproc opencv_features2d WRAP python)

**NEW**
ocv_define_module(saliency opencv_imgproc opencv_features2d WRAP python java)

### Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [x] The PR is proposed to the proper branch
- [x] There is a reference to the original bug report and related work
- [ ] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
      Patch to opencv_extra has the same branch name.
- [x] The feature is well documented and sample code can be built with the project CMake

Author: Akhil-Chaturvedi

modules/saliency/CMakeLists.txt

@@ -4,6 +4,6 @@ endif()
 
 set(the_description "Saliency API")
 
-ocv_define_module(saliency opencv_imgproc opencv_features2d WRAP python)
+ocv_define_module(saliency opencv_imgproc opencv_features2d WRAP python java)
 
 ocv_warnings_disable(CMAKE_CXX_FLAGS -Woverloaded-virtual)

modules/saliency/include/opencv2/saliency/saliencySpecializedClasses.hpp

@@ -87,7 +87,7 @@ class CV_EXPORTS_W StaticSaliencySpectralResidual : public StaticSaliency
   }
 
   CV_WRAP void read( const FileNode& fn ) CV_OVERRIDE;
-  void write( FileStorage& fs ) const CV_OVERRIDE;
+  CV_WRAP void write( FileStorage& fs ) const CV_OVERRIDE;
 
   CV_WRAP int getImageWidth() const
   {
@@ -308,9 +308,6 @@ class CV_EXPORTS_W ObjectnessBING : public Objectness
     return computeSaliencyImpl( image, saliencyMap );
   }
 
-  CV_WRAP void read();
-  CV_WRAP void write() const;
-
   /** @brief Return the list of the rectangles' objectness value,
 
     in the same order as the *vector\<Vec4i\> objectnessBoundingBox* returned by the algorithm (in

modules/saliency/src/BING/objectnessBING.cpp

@@ -448,21 +448,12 @@ bool ObjectnessBING::matRead( const std::string& filename, Mat& _M )
   M.copyTo( _M );
   return true;
 }
+
 std::vector<float> ObjectnessBING::getobjectnessValues()
 {
   return objectnessValues;
 }
 
-void ObjectnessBING::read()
-{
-
-}
-
-void ObjectnessBING::write() const
-{
-
-}
-
 bool ObjectnessBING::computeSaliencyImpl( InputArray image, OutputArray objectnessBoundingBox )
 {
   ValStructVec<float, Vec4i> finalBoxes;