Add some methods to get information from the library.

Else, the library is useless.

src/android/book.cpp

@@ -39,7 +39,7 @@ Java_org_kiwix_kiwixlib_Book_dispose(JNIEnv* env, jobject thisObj)
 
 #define BOOK (getPtr<kiwix::Book>(env, thisObj))
 
-#define METHOD(retType, name) JNIEXPORT retType JNICALL \
+#define GETTER(retType, name) JNIEXPORT retType JNICALL \
 Java_org_kiwix_kiwixlib_Book_##name (JNIEnv* env, jobject thisObj) \
 { \
   auto cRet = BOOK->name(); \
@@ -47,21 +47,23 @@ Java_org_kiwix_kiwixlib_Book_##name (JNIEnv* env, jobject thisObj) \
   return ret; \
 }
 
-METHOD(jstring, getId)
-METHOD(jstring, getPath)
-METHOD(jboolean, isPathValid)
-METHOD(jstring, getTitle)
-METHOD(jstring, getDescription)
-METHOD(jstring, getLanguage)
-METHOD(jstring, getCreator)
-METHOD(jstring, getPublisher)
-METHOD(jstring, getDate)
-METHOD(jstring, getUrl)
-METHOD(jstring, getName)
-METHOD(jstring, getTags)
-METHOD(jlong, getArticleCount)
-METHOD(jlong, getMediaCount)
-METHOD(jlong, getSize)
-METHOD(jstring, getFavicon)
-METHOD(jstring, getFaviconUrl)
-METHOD(jstring, getFaviconMimeType)
+GETTER(jstring, getId)
+GETTER(jstring, getPath)
+GETTER(jboolean, isPathValid)
+GETTER(jstring, getTitle)
+GETTER(jstring, getDescription)
+GETTER(jstring, getLanguage)
+GETTER(jstring, getCreator)
+GETTER(jstring, getPublisher)
+GETTER(jstring, getDate)
+GETTER(jstring, getUrl)
+GETTER(jstring, getName)
+GETTER(jstring, getTags)
+GETTER(jlong, getArticleCount)
+GETTER(jlong, getMediaCount)
+GETTER(jlong, getSize)
+GETTER(jstring, getFavicon)
+GETTER(jstring, getFaviconUrl)
+GETTER(jstring, getFaviconMimeType)
+
+#undef GETTER

src/android/library.cpp

@@ -60,3 +60,34 @@ Java_org_kiwix_kiwixlib_Library_addBook(
   }
   return false;
 }
+
+METHOD(jobject, Library, getBookById, jstring id) {
+  auto cId = jni2c(id, env);
+  auto cBook = new kiwix::Book(LIBRARY->getBookById(cId));
+  jclass cls = env->FindClass("org/kiwix/kiwixlib/Book");
+  jmethodID constructorId = env->GetMethodID(cls, "<init>", "()V");
+  jobject book = env->NewObject(cls, constructorId);
+  setPtr(env, book, cBook);
+  return book;
+}
+
+METHOD(jint, Library, getBookCount, jboolean localBooks, jboolean remoteBooks) {
+  return LIBRARY->getBookCount(localBooks, remoteBooks);
+}
+
+METHOD0(jobjectArray, Library, getBooksIds) {
+  return c2jni(LIBRARY->getBooksIds(), env);
+}
+
+METHOD0(jobjectArray, Library, getBooksLanguages) {
+  return c2jni(LIBRARY->getBooksLanguages(), env);
+}
+
+METHOD0(jobjectArray, Library, getBooksCreators) {
+  return c2jni(LIBRARY->getBooksCreators(), env);
+}
+
+METHOD0(jobjectArray, Library, getBooksPublisher) {
+  return c2jni(LIBRARY->getBooksPublishers(), env);
+}
+

src/android/org/kiwix/kiwixlib/Library.java

@@ -19,12 +19,23 @@
 
 package org.kiwix.kiwixlib;
 
+import org.kiwix.kiwixlib.Book;
 import org.kiwix.kiwixlib.JNIKiwixException;
 
 public class Library
 {
   public native boolean addBook(String path) throws JNIKiwixException;
 
+  public native Book getBookById(String id);
+  public native int  getBookCount(boolean localBooks, boolean remoteBooks);
+
+  public native String[] getBooksIds();
+//  public native String[] filter(Filter filter);
+
+  public native String[] getBooksLanguages();
+  public native String[] getBooksCreators();
+  public native String[] getBooksPublishers();
+
   public Library()
   {
     allocate();

src/android/utils.h

@@ -26,16 +26,23 @@
 
 #include <pthread.h>
 #include <string>
+#include <vector>
 
 extern pthread_mutex_t globalLock;
 
+template<typename T>
+void setPtr(JNIEnv* env, jobject thisObj, T* ptr)
+{
+  jclass thisClass = env->GetObjectClass(thisObj);
+  jfieldID fieldId = env->GetFieldID(thisClass, "nativeHandle", "J");
+  env->SetLongField(thisObj, fieldId, reinterpret_cast<jlong>(ptr));
+}
+
 template<typename T, typename ...Args>
 void allocate(JNIEnv* env, jobject thisObj, Args && ...args)
 {
-  jclass thisClass = env->GetObjectClass(thisObj);
-  jfieldID fidNumber = env->GetFieldID(thisClass, "nativeHandle", "J");
   T* ptr = new T(std::forward<Args>(args)...);
-  env->SetLongField(thisObj, fidNumber, reinterpret_cast<jlong>(ptr));
+  setPtr(env, thisObj, ptr);
 }
 
 template<typename T>
@@ -52,6 +59,14 @@ void dispose(JNIEnv* env, jobject thisObj)
   delete getPtr<T>(env, thisObj);
 }
 
+#define METHOD0(retType, class, name) \
+JNIEXPORT retType JNICALL Java_org_kiwix_kiwixlib_##class##_##name( \
+ JNIEnv* env, jobject thisObj)
+
+#define METHOD(retType, class, name, ...) \
+JNIEXPORT retType JNICALL Java_org_kiwix_kiwixlib_##class##_##name( \
+  JNIEnv* env, jobject thisObj, __VA_ARGS__)
+
 inline jfieldID getHandleField(JNIEnv* env, jobject obj)
 {
   jclass c = env->GetObjectClass(obj);
@@ -59,6 +74,12 @@ inline jfieldID getHandleField(JNIEnv* env, jobject obj)
   return env->GetFieldID(c, "nativeHandle", "J");
 }
 
+inline jobjectArray createArray(JNIEnv* env, size_t length, const std::string& type_sig)
+{
+  jclass c = env->FindClass(type_sig.c_str());
+  return env->NewObjectArray(length, c, NULL);
+}
+
 class Lock
 {
  protected:
@@ -126,6 +147,7 @@ template<> struct JType<long>{ typedef jlong type_t; };
 template<> struct JType<uint64_t> { typedef jlong type_t; };
 template<> struct JType<uint32_t> { typedef jlong type_t; };
 template<> struct JType<std::string>{ typedef jstring type_t; };
+template<> struct JType<std::vector<std::string>>{ typedef jobjectArray type_t; };
 
 template<typename T>
 inline typename JType<T>::type_t c2jni(const T& val, JNIEnv* env) {
@@ -141,6 +163,18 @@ inline jstring c2jni(const std::string& val, JNIEnv* env)
   return env->NewStringUTF(val.c_str());
 }
 
+template<>
+inline jobjectArray c2jni(const std::vector<std::string>& val, JNIEnv* env)
+{
+  auto array = createArray(env, val.size(), "java/lang/String");
+  size_t index = 0;
+  for (auto& elem: val) {
+    auto jElem = c2jni(elem, env);
+    env->SetObjectArrayElement(array, index++, jElem);
+  }
+  return array;
+}
+
 
 /* jni2c type conversion functions */
 inline bool jni2c(const jboolean& val) { return val == JNI_TRUE; }