[WIP] Use a common class Wrapper and IterWrapper to wrapp native resource.

Native resource (pointer to shared_ptr) is stored as a long in the
`Wrapper.Resource` class.

As Wrapper implements AutoCloseable and we register the (java) resource
to be cleaned at object destruction, we now properly delete the native
resource.


This also adding new macro to avoid writting the class name and so
reduce potential typos.

Author: mgautierfr

lib/build.gradle

@@ -26,11 +26,11 @@ ext {
 
 apply from: 'publish.gradle'
 android {
-    compileSdk 32
+    compileSdk 33
 
     defaultConfig {
 
-        minSdk 21
+        minSdk 33
         targetSdk 32
         versionCode 1
         versionName "1.0"
@@ -285,5 +285,5 @@ task checkCurrentJavaVersion() {
 
 task generateHeaderFilesFromJavaWrapper(type: Exec) {
     workingDir "${projectDir}/src/main/java/org/kiwix/"
-    commandLine 'bash', '-c', "javac -h ${buildDir}/include/javah_generated/ -d ${buildDir}/libzim/ libzim/*.java libkiwix/*.java"
+    commandLine 'bash', '-c', "javac -h ${buildDir}/include/javah_generated/ -d ${buildDir}/libzim/ *.java libzim/*.java libkiwix/*.java"
 }

lib/src/main/cpp/CMakeLists.txt

@@ -10,6 +10,7 @@ add_library(
         zim_wrapper
 
         SHARED
+        wrapper.cpp
         libzim/archive.cpp
         libzim/entry.cpp
         libzim/entry_iterator.cpp
@@ -45,6 +46,7 @@ add_library(
         kiwix_wrapper
 
         SHARED
+        wrapper.cpp
         libkiwix/book.cpp
         libkiwix/filter.cpp
         libkiwix/kiwixicu.cpp

lib/src/main/cpp/libkiwix/book.cpp

@@ -29,13 +29,11 @@
 #define TYPENAME libkiwix_Book
 #include <macros.h>
 
-METHOD0(void, allocate)
+METHOD0(jobject, getNativeBook)
 {
-  SET_PTR(std::make_shared<NATIVE_TYPE>());
+  return NEW_RESOURCE(std::make_shared<NATIVE_TYPE>());
 }
 
-DISPOSE
-
 METHOD(void, update__Lorg_kiwix_libkiwix_Book_2, jobject otherBook)
 {
   THIS->update(*getPtr<kiwix::Book>(env, otherBook));
@@ -93,12 +91,12 @@ METHOD0(jobjectArray, getIllustrations) {
   jobjectArray retArray = createArray(env, illustrations.size(), "org/kiwix/libkiwix/Illustration");
   size_t index = 0;
   for (auto illu: illustrations) {
-    auto wrapper = BUILD_WRAPPER("org/kiwix/libkiwx/Illustration", illu);
+    auto wrapper = BUILD_WRAPPER(illu);
     env->SetObjectArrayElement(retArray, index++, wrapper);
   }
   return retArray;
 }
 
 METHOD(jobject, getIllustration, jint size) {
-  return BUILD_WRAPPER("org/kiwix/libkiwix/Illustration", THIS->getIllustration(TO_C(size)));
+  return BUILD_WRAPPER(THIS->getIllustration(TO_C(size)));
 }

lib/src/main/cpp/libkiwix/filter.cpp

@@ -28,15 +28,11 @@
 #define TYPENAME libkiwix_Filter
 #include "macros.h"
 
-
-
 /* Kiwix Reader JNI functions */
-METHOD0(void, allocate) {
-  SET_PTR(std::make_shared<NATIVE_TYPE>());
+METHOD0(jobject, getNativeFilter) {
+  return NEW_RESOURCE(std::make_shared<NATIVE_TYPE>());
 }
 
-DISPOSE
-
 #define FORWARD(name, args_type) \
 METHOD(jobject, name, args_type value) { \
   THIS->name(jni2c(value, env)); \

lib/src/main/cpp/libkiwix/kiwixserver.cpp

@@ -32,21 +32,14 @@
 
 
 /* Kiwix Reader JNI functions */
-METHOD(void, setNativeServer, jobject jLibrary)
+METHOD(jobject, buildNativeServer, jobject jLibrary)
 {
   LOG("Attempting to create server");
-  try {
-    auto library = getPtr<kiwix::Library>(env, jLibrary);
-    SET_PTR(std::make_shared<NATIVE_TYPE>(library.get()));
-  } catch (std::exception& e) {
-    LOG("Error creating the server");
-    LOG("%s", e.what());
-  }
+  auto library = getPtr<kiwix::Library>(env, jLibrary);
+  return NEW_RESOURCE(std::make_shared<NATIVE_TYPE>(library.get()));
 }
 
 
-DISPOSE
-
 /* Kiwix library functions */
 METHOD(void, setRoot, jstring root)
 {

lib/src/main/cpp/libkiwix/library.cpp

@@ -29,12 +29,11 @@
 #include "macros.h"
 
 /* Kiwix Reader JNI functions */
-METHOD0(void, setNativeHandler)
+METHOD0(jobject, buildNativeLibrary)
 {
-  SET_PTR(std::make_shared<NATIVE_TYPE>());
+  return NEW_RESOURCE(std::make_shared<NATIVE_TYPE>());
 }
 
-DISPOSE
 
 /* Kiwix library functions */
 METHOD(jboolean, addBook, jobject book)
@@ -50,11 +49,11 @@ METHOD(jboolean, addBook, jobject book)
 }
 
 METHOD(jobject, getBookById, jstring id) {
-  return BUILD_WRAPPER("org/kiwix/libkiwix/Book", THIS->getBookById(TO_C(id)));
+  return BUILD_WRAPPER(THIS->getBookById(TO_C(id)));
 }
 
 METHOD(jobject, getArchiveById, jstring id) {
-  return BUILD_WRAPPER("org/kiwix/libzim/Archive", THIS->getArchiveById(TO_C(id)));
+  return BUILD_WRAPPER(THIS->getArchiveById(TO_C(id)));
 }
 
 METHOD(jboolean, removeBookById, jstring id) {

lib/src/main/cpp/libkiwix/manager.cpp

@@ -28,14 +28,12 @@
 #define TYPENAME libkiwix_Manager
 #include <macros.h>
 
-METHOD(void, allocate, jobject libraryObj)
+METHOD(jobject, buildNativeManager, jobject libraryObj)
 {
   auto lib = getPtr<kiwix::Library>(env, libraryObj);
-  SET_PTR(std::make_shared<NATIVE_TYPE>(lib.get()));
+  return NEW_RESOURCE(std::make_shared<NATIVE_TYPE>(lib.get()));
 }
 
-DISPOSE
-
 /* Kiwix manager functions */
 METHOD(jboolean, readFile, jstring path)
 {

lib/src/main/cpp/libzim/archive.cpp

@@ -36,18 +36,13 @@
 #include <macros.h>
 
 /* Kiwix Reader JNI functions */
-METHOD(void, setNativeArchive, jstring filename)
+METHOD(jobject, buildNativeArchive, jstring filename)
 {
   std::string cPath = TO_C(filename);
 
   LOG("Attempting to create reader with: %s", cPath.c_str());
-  try {
-    auto archive = std::make_shared<zim::Archive>(cPath);
-    SET_PTR(archive);
-  } catch (std::exception& e) {
-    LOG("Error opening ZIM file");
-      LOG("%s", e.what());
-  }
+  auto archive = std::make_shared<NATIVE_TYPE>(cPath);
+  return NEW_RESOURCE(archive);
 }
 
 namespace
@@ -70,7 +65,7 @@ int jni2fd(const jobject& fdObj, JNIEnv* env)
 
 } // unnamed namespace
 
-JNIEXPORT void JNICALL Java_org_kiwix_libzim_Archive_setNativeArchiveByFD(
+JNIEXPORT jobject JNICALL Java_org_kiwix_libzim_Archive_buildNativeArchiveByFD(
     JNIEnv* env, jobject thisObj, jobject fdObj)
 {
 #ifndef _WIN32
@@ -79,18 +74,16 @@ JNIEXPORT void JNICALL Java_org_kiwix_libzim_Archive_setNativeArchiveByFD(
   LOG("Attempting to create reader with fd: %d", fd);
   try {
     auto archive = std::make_shared<zim::Archive>(fd);
-    SET_PTR(archive);
-  } catch (std::exception& e) {
-    LOG("Error opening ZIM file");
-       LOG("%s", e.what());
-  }
+    return NEW_RESOURCE(archive);
+  } CATCH("Error opening ZIM file")
 #else
   jclass exception = env->FindClass("java/lang/UnsupportedOperationException");
   env->ThrowNew(exception, "org.kiwix.libzim.Archive.setNativeArchiveByFD() is not supported under Windows");
 #endif
+  return nullptr;
 }
 
-JNIEXPORT void JNICALL Java_org_kiwix_libzim_Archive_setNativeArchiveEmbedded(
+JNIEXPORT jobject JNICALL Java_org_kiwix_libzim_Archive_buildNativeArchiveEmbedded(
     JNIEnv* env, jobject thisObj, jobject fdObj, jlong offset, jlong size)
 {
 #ifndef _WIN32
@@ -99,19 +92,15 @@ JNIEXPORT void JNICALL Java_org_kiwix_libzim_Archive_setNativeArchiveEmbedded(
   LOG("Attempting to create reader with fd: %d", fd);
   try {
     auto archive = std::make_shared<zim::Archive>(fd, offset, size);
-    SET_PTR(archive);
-  } catch (std::exception& e) {
-    LOG("Error opening ZIM file");
-       LOG("%s", e.what());
-  }
+    return NEW_RESOURCE(archive);
+  } CATCH("Error opening ZIM file")
 #else
   jclass exception = env->FindClass("java/lang/UnsupportedOperationException");
   env->ThrowNew(exception, "org.kiwix.libzim.Archive.setNativeArchiveEmbedded() is not supported under Windows");
 #endif
+  return nullptr;
 }
 
-DISPOSE
-
 GETTER(jstring, getFilename)
 GETTER(jlong, getFilesize)
 GETTER(jint, getAllEntryCount)
@@ -128,13 +117,13 @@ METHOD(jstring, getMetadata, jstring name) {
 }
 
 METHOD(jobject, getMetadataItem, jstring name) {
-  return BUILD_WRAPPER("org/kiwix/libzim/Item", THIS->getMetadataItem(TO_C(name)));
+  return BUILD_WRAPPER(THIS->getMetadataItem(TO_C(name)));
 }
 
 GETTER(jobjectArray, getMetadataKeys)
 
 METHOD(jobject, getIllustrationItem, jint size) {
-  return BUILD_WRAPPER("org/kiwix/libzim/Item", THIS->getIllustrationItem(TO_C(size)));
+  return BUILD_WRAPPER(THIS->getIllustrationItem(TO_C(size)));
 }
 
 METHOD(jboolean, hasIllustration, jint size) {
@@ -144,41 +133,41 @@ METHOD(jboolean, hasIllustration, jint size) {
 GETTER(jlongArray, getIllustrationSizes)
 
 METHOD(jobject, getEntryByPath__Ljava_lang_String_2, jstring path) {
-  return BUILD_WRAPPER("org/kiwix/libzim/Entry", THIS->getEntryByPath(TO_C(path)));
+  return BUILD_WRAPPER(THIS->getEntryByPath(TO_C(path)));
 }
 
 METHOD(jobject, getEntryByPath__I, jint index) {
-  return BUILD_WRAPPER("org/kiwix/libzim/Entry", THIS->getEntryByPath(TO_C(index)));
+  return BUILD_WRAPPER(THIS->getEntryByPath(TO_C(index)));
 }
 
 METHOD(jboolean, hasEntryByPath, jstring path) {
   return TO_JNI(THIS->hasEntryByPath(TO_C(path)));
 }
 
 METHOD(jobject, getEntryByTitle__Ljava_lang_String_2, jstring title) {
-  return BUILD_WRAPPER("org/kiwix/libzim/Entry", THIS->getEntryByTitle(TO_C(title)));
+  return BUILD_WRAPPER(THIS->getEntryByTitle(TO_C(title)));
 }
 
 METHOD(jobject, getEntryByTitle__I, jint index) {
-  return BUILD_WRAPPER("org/kiwix/libzim/Entry", THIS->getEntryByTitle(TO_C(index)));
+  return BUILD_WRAPPER(THIS->getEntryByTitle(TO_C(index)));
 }
 
 METHOD(jboolean, hasEntryByTitle, jstring title) {
   return TO_JNI(THIS->hasEntryByPath(TO_C(title)));
 }
 
 METHOD(jobject, getEntryByClusterOrder, jint index) {
-  return BUILD_WRAPPER("org/kiwix/libzim/Entry", THIS->getEntryByClusterOrder(TO_C(index)));
+  return BUILD_WRAPPER(THIS->getEntryByClusterOrder(TO_C(index)));
 }
 
 METHOD0(jobject, getMainEntry) {
-  return BUILD_WRAPPER("org/kiwix/libzim/Entry", THIS->getMainEntry());
+  return BUILD_WRAPPER(THIS->getMainEntry());
 }
 
 GETTER(jboolean, hasMainEntry)
 
 METHOD0(jobject, getRandomEntry) {
-  return BUILD_WRAPPER("org/kiwix/libzim/Entry", THIS->getRandomEntry());
+  return BUILD_WRAPPER(THIS->getRandomEntry());
 }
 
 GETTER(jboolean, hasFulltextIndex)
@@ -192,62 +181,57 @@ GETTER(jboolean, hasNewNamespaceScheme)
 #define ITER_BY_PATH 0
 #define ITER_BY_TITLE 1
 #define ITER_EFFICIENT 2
+
+
+// No use of the macro BUILD_WRAPPER as `EntryIterator` takes a integer(I) to
+// track the order. So the signature of the constructor is not the same.
+// The same way, as we are building a iterator, it has two nativeHandle (for begin and end).
 METHOD0(jobject, iterByPath) {
   auto range = THIS->iterByPath();
-  jclass objClass = env->FindClass("org/kiwix/libzim/EntryIterator");
-  jmethodID initMethod = env->GetMethodID(objClass, "<init>", "(I)V");
-  jobject obj = env->NewObject(objClass, initMethod, ITER_BY_PATH);
-  SET_HANDLE(zim::Archive::iterator<zim::EntryOrder::pathOrder>, obj, range.begin());
+  auto beginIter = NEW_RESOURCE(range.begin());
+  auto endIter = NEW_RESOURCE(range.end());
 
-  auto end_ptr = std::make_shared<zim::Archive::iterator<zim::EntryOrder::pathOrder>>(range.end());
-  setPtr(env, obj, std::move(end_ptr), "nativeHandleEnd");
-  return obj;
+  jclass wrapperClass = env->FindClass("org/kiwix/libzim/EntryIterator");
+  jmethodID initMethod = env->GetMethodID(wrapperClass, "<init>", "(org/kiwix/Wrapper/Resource;org/kiwix/Wrapper/Resource)V");
+  return env->NewObject(wrapperClass, initMethod, beginIter, endIter);
 }
 
 METHOD0(jobject, iterByTitle) {
   auto range = THIS->iterByTitle();
-  jclass objClass = env->FindClass("org/kiwix/libzim/EntryIterator");
-  jmethodID initMethod = env->GetMethodID(objClass, "<init>", "(I)V");
-  jobject obj = env->NewObject(objClass, initMethod, ITER_BY_TITLE);
-  SET_HANDLE(zim::Archive::iterator<zim::EntryOrder::titleOrder>, obj, range.begin());
+  auto beginIter = NEW_RESOURCE(range.begin());
+  auto endIter = NEW_RESOURCE(range.end());
 
-  auto end_ptr = std::make_shared<zim::Archive::iterator<zim::EntryOrder::titleOrder>>(range.end());
-  setPtr(env, obj, std::move(end_ptr), "nativeHandleEnd");
-  return obj;
+  jclass wrapperClass = env->FindClass("org/kiwix/libzim/EntryIterator");
+  jmethodID initMethod = env->GetMethodID(wrapperClass, "<init>", "(org/kiwix/Wrapper/Resource;org/kiwix/Wrapper/Resource)V");
+  return env->NewObject(wrapperClass, initMethod, beginIter, endIter);
 }
 
 METHOD0(jobject, iterEfficient) {
   auto range = THIS->iterEfficient();
-  jclass objClass = env->FindClass("org/kiwix/libzim/EntryIterator");
-  jmethodID initMethod = env->GetMethodID(objClass, "<init>", "(I)V");
-  jobject obj = env->NewObject(objClass, initMethod, ITER_EFFICIENT);
-  SET_HANDLE(zim::Archive::iterator<zim::EntryOrder::efficientOrder>, obj, range.begin());
+  auto beginIter = NEW_RESOURCE(range.begin());
+  auto endIter = NEW_RESOURCE(range.end());
 
-  auto end_ptr = std::make_shared<zim::Archive::iterator<zim::EntryOrder::efficientOrder>>(range.end());
-  setPtr(env, obj, std::move(end_ptr), "nativeHandleEnd");
-  return obj;
+  jclass wrapperClass = env->FindClass("org/kiwix/libzim/EntryIterator");
+  jmethodID initMethod = env->GetMethodID(wrapperClass, "<init>", "(org/kiwix/Wrapper/Resource;org/kiwix/Wrapper/Resource)V");
+  return env->NewObject(wrapperClass, initMethod, beginIter, endIter);
 }
 
 METHOD(jobject, findByPath, jstring path) {
   auto range = THIS->findByPath(TO_C(path));
-  jclass objClass = env->FindClass("org/kiwix/libzim/EntryIterator");
-  jmethodID initMethod = env->GetMethodID(objClass, "<init>", "(I)V");
-  jobject obj = env->NewObject(objClass, initMethod, ITER_BY_PATH);
-  SET_HANDLE(zim::Archive::iterator<zim::EntryOrder::pathOrder>, obj, range.begin());
+  auto beginIter = NEW_RESOURCE(range.begin());
+  auto endIter = NEW_RESOURCE(range.end());
 
-  auto end_ptr = std::make_shared<zim::Archive::iterator<zim::EntryOrder::pathOrder>>(range.end());
-  setPtr(env, obj, std::move(end_ptr), "nativeHandleEnd");
-  return obj;
+  jclass wrapperClass = env->FindClass("org/kiwix/libzim/EntryIterator");
+  jmethodID initMethod = env->GetMethodID(wrapperClass, "<init>", "(org/kiwix/Wrapper/Resource;org/kiwix/Wrapper/Resource)V");
+  return env->NewObject(wrapperClass, initMethod, beginIter, endIter);
 }
 
 METHOD(jobject, findByTitle, jstring title) {
   auto range = THIS->findByTitle(TO_C(title));
-  jclass objClass = env->FindClass("org/kiwix/libzim/EntryIterator");
-  jmethodID initMethod = env->GetMethodID(objClass, "<init>", "(I)V");
-  jobject obj = env->NewObject(objClass, initMethod, ITER_BY_TITLE);
-  SET_HANDLE(zim::Archive::iterator<zim::EntryOrder::titleOrder>, obj, range.begin());
-
-  auto end_ptr = std::make_shared<zim::Archive::iterator<zim::EntryOrder::titleOrder>>(range.end());
-  setPtr(env, obj, std::move(end_ptr), "nativeHandleEnd");
-  return obj;
+  auto beginIter = NEW_RESOURCE(range.begin());
+  auto endIter = NEW_RESOURCE(range.end());
+
+  jclass wrapperClass = env->FindClass("org/kiwix/libzim/EntryIterator");
+  jmethodID initMethod = env->GetMethodID(wrapperClass, "<init>", "(org/kiwix/Wrapper/Resource;org/kiwix/Wrapper/Resource)V");
+  return env->NewObject(wrapperClass, initMethod, beginIter, endIter);
 }