Java Native Interface (JNI) framework wrapper, which uses new C++ features in order to add type safety.
- Boost 1.61 or higher (http://www.boost.org)
- C++14 compatible compiler (clang >= 3.8, gcc >= 6.0)
- google test for UT (>= 1.8)
With below silly Java class:
package jni.test;
public class JNITest {
private int privatePrimitiveField;
private String privateObjectField;
public JNITest(int primitiveParam, String objectParam) {
this.privatePrimitiveField = primitiveParam;
this.privateObjectField = objectParam;
}
public int getPrimitiveField() {
return privatePrimitiveField;
}
public String getStringField() {
return privateObjectField;
}
}Get back to C++ and prepare your Java class description:
#include <jni/method_signature.hpp>
//class description is a template that must derive it's sole template parameter
template<typename T>
struct MyJNIClass: T
{
//path to your class package
using class_path_t = typestring_is("jni/test/MyJNIClass");
//here you create constructor signature: it returns object of your class, obviously, and takes one integer and string in turn
MAKE_JAVA_CONSTRUCTORS(jni::types::Object<::MyJNIClass>(jni::types::Int, jni::types::String))
//similarly you can declare methods
MAKE_JAVA_METHOD(getPrimitiveField, jni::types::Method<jni::types::Int()>)
MAKE_JAVA_METHOD(getStringField, jni::types::Method<jni::types::String()>)
};Create JVM:
#include <virtual_machine.hpp>
...
jni::VirtualMachine vm({"-Djava.class.path=path-to-your-jar-file"});Create some classes and work with them:
...
auto myClass = vm.loadClass<MyJNIClass>();
auto javaObject = myClass.Construct(5, "123ads");
cout << javaObject.getPrimitiveField() << " '" << javaObject.getStringField() << "'" << endl;
...It can't be simpler!
* registering of native methods
* Java monitors support
* arrays support
* class field access