All Questions
Tagged with java-native-interface c++
2,809 questions
1
vote
0
answers
50
views
Using SWIG to handle char* argument that is modified by the method from Java to C++
I have a C++ method :
class classA
{
public:
bool methodA(const char* a, const int b, char* c);
}
This is used in the C++ application as follows:
int q = 5;
char returnOutput[512] = "...
1
vote
1
answer
65
views
Why JNI env (JNI interface pointer) is thread specific?
Two doubts from JNI Design Overview docs:
The JNI interface pointer is only valid in the current thread. A native method, therefore, must not pass the interface pointer from one thread to another. A ...
- 257
1
vote
1
answer
85
views
C++ JNI:Error occurred during initialization of VMFailed setting boot class path
First run main.exe it said can not find jvm.dll
So I copy jvm.dll from C:\Program Files\Zulu\zulu-21\bin\server to ./
Then this is my workspace.
ls
jvm.dll main.cpp main.exe main.obj
But second ...
- 59
0
votes
1
answer
91
views
Cannot load a native JNI library
I'm working on a Minecraft library for my own mods to use and i ran into a problem with JNI.
I'm still new to the JNI and c++ stuff so i might've made a mistake but after hours of searching i didn't ...
0
votes
1
answer
83
views
How do I properly pre-load ASAN libraries on macOS with Java binary (JNI library) with SIP enabled
We have a large C++ library for which we have created Java bindings using SWIG (so a JNI shared library). We build for and run tests on many build platforms across macOS, Linux, and Windows; debug and ...
- 3,168
0
votes
0
answers
28
views
Call CallVoidMethod multiple time cause crash
I'm trying to use JSI and JNI in a React-Native app for sending ArrayBuffer without encoding data.
For this, I have a C++ function receiveDataFromCpp():
extern "C"
JNIEXPORT void JNICALL
...
- 1,496
1
vote
1
answer
53
views
Unable to set timestamp on Android MediaCodec Image object from native c++ code
I have an created a queue to store images from ImageReader in cpp.
while copying the queued items to the Image object from MediaCodec.getInputImage(index) method I'm facing an issue where the byte ...
- 25
2
votes
1
answer
96
views
Android Native Activity cannot FindClass from external AAR library
I'm trying to build a dynamic library (OpenXR api_layer) in c++ that communicates with a java SDK but I'm having issues with the JNI part of the implementation, from the OpenXR Create Layer function I ...
- 21
-1
votes
1
answer
38
views
c++ using JNI: AttachCurrentThread returns -1
I use the JNI in a cpp project, and JNI_GetCreatedJavaVMs is the function how I get JavaVM*.
In the project, there is one cpp function which use JNI. And I when use it in one func, it works well. But ...
- 1
0
votes
1
answer
23
views
Compiler opton for detecting missing JNI prototypes?
While going through the exercise of renaming my namespace, I occasionally get tripped up by a situation where the function definitions incorporate the OLD packagename in the fct name. For example:
...
0
votes
0
answers
43
views
How to attach visual studio code to a java process on linux loading *.so files via JNI
I have the following setup on our debug machines:
wsl running Ubuntu linux,
main code is written in C++ and exposed as shared objects, compilation done using g++,
these shared objects are then loaded ...
- 11
0
votes
0
answers
58
views
JNI Crashing when using from other header file
When i try to use the JNI pointer from another file, the main process crashes, not sure how to look up the crash reason neither.
I've a cpp header file to handle java stuff
using ...
- 88
-1
votes
1
answer
159
views
Android App using C++ for serial USB access
I'm developing an Android application that needs to access a third-party library written in C that accesses the serial port through the command (*pSerialHandle) = open(deviceName, O_RDWR | O_NOCTTY | ...
- 151
-1
votes
1
answer
147
views
JNI CallStaticObjectMethod is causing crash with Java 21
The company I work for recently moved to Java 21 from Java 8, which updated the JNI version as well that is used with interoperatibility with C++. All the function (written in C++) called through JNI ...
- 356
0
votes
1
answer
83
views
How to kill android application from c++
I am developing a library to detect rooted environment & I am able to achieve that goal but since the tools like frida, lsposed etc exists, An attacker can be easily able to hook libc's function ...
- 102
-2
votes
1
answer
152
views
How can jni be leveraged for an abstract class?
I am just getting familiar with jni/java and the workflow where we want to invoke methods that are written in native code but what i am unable to understand yet is how JNI can be leveraged if the ...
- 1,217
0
votes
1
answer
95
views
Invoking Java Methods from C++, class not found
I was experimenting with how to invoke the Methods from C++, I got this far:
#include <jni.h>
#include <iostream>
// Function to create the JVM and call the sayHi method
void ...
- 73
1
vote
0
answers
129
views
JNI DETECTED ERROR IN APPLICATION: input is not valid Modified UTF-8: illegal start byte 0x80
JNI method NewStringUTF expects input as a modified UTF8 string, the difference between Standard UTF-8 and modified UTF-8 is in how it handles the null (U+0000) character. In standard UTF-8, the null ...
- 257
2
votes
1
answer
321
views
How to represent C++ class in java to be used via FFI?
I have following sample code in C++
class SomeClass: public ISomeClass
{
private:
int myMember;
public:
SomeClass(int value) : myMember(value) {}
__declspec(dllexport)
int GetCount() ...
- 2,248
0
votes
0
answers
121
views
React Native Javascript Native Interface (JSI) Linking failure on Android
I'm trying to get a JavaScript Native Interface module working on Android.
Can anyone help?
I can compile the app including the CPP library. The app opens, runs the MyJsiNamespace::...
- 3,699
3
votes
0
answers
63
views
Trying to pass a structure from C++ to Kotlin through JNI, and I am having to do endian conversion and bit shifting, is there a better way to do this? [duplicate]
I have a union defined in C++, as follows:
static union uns {
uint64_t data;
struct {
uint64_t a : 32;
uint64_t b : ...
0
votes
1
answer
87
views
DllMain is not called after injection
I had a working code that interacted with JNI. When I injected the DLL, everything worked. I decided to improve my program and add a GUI using ImGui and MinHook. After that, DllMain stopped being ...
- 41
1
vote
1
answer
86
views
How can I include jar files for clojure in JNI inside a c++ binary created with bazel
Hello I am working on this project: https://github.com/svazqz/plClojure
But currently I am facing an issue after building the c++ binary, when I run the file create after the build step I get:
#
# A ...
- 11
3
votes
1
answer
161
views
Why SIGSEGV behaves differently from other Exception codes in Android?
I am building an Android application with Native code. I want to handle the exceptions such as SIGSEGV, SIGFPE, SIGILL, etc.
My objective is that in the unlikely scenario that one of them occurs, I am ...
- 91
0
votes
1
answer
134
views
What is the best container to store an {arbitrary jobject}'s data in C++?
I am writing an app that should use jobject's fields multiple times at a great speed. Since retrieving fields from jobjects is pretty slow, I want to do it once and then read and write fields of some ...
0
votes
1
answer
208
views
I don't know how to solve "local reference table overflow" error in android JNI
I am experiencing a local reference overflow error when running my algorithm written in JNI. The code works fine up to 2000-3000 iterations, but after that, it crashes with the error message "...
- 35
0
votes
0
answers
106
views
Invoke jar from C++ using JNI
I am trying to call a .jar file from native code. It seems no matter what I try, I always get the following error:
Error occurred during initialization of VM
Failed setting boot class path.
I have ...
user16581312
0
votes
1
answer
69
views
JNI - Call java method with a Functional Interface parameter from cpp
I would to know if there is a way to call a java method from cpp with a Functional Interface and use this callback inside my java code.
This is my code :
Main.java
import java.util.function.Consumer;
...
- 1,005
0
votes
0
answers
54
views
Generate SWIG JNI for reference pointer
I am trying to generate JNI wrappers using SWIG (4.1) for the following C++ code. The Header.h looks like this:
class Butler
{
public:
Butler();
~Butler();
void setHoursAvailable(int ...
- 21
0
votes
1
answer
104
views
Unable to create or access file at path: /storage/self/primary/Download/ from native-lib.cpp in android studio
In one of my project it requires me to create/read/write file at path /storage/self/primary/Download/ from .cpp file in android studio,but I'm unable to access to that path.
As of now I am able to ...
- 1
1
vote
1
answer
145
views
Unable to find compiled c++ library function
I have a file called libmylibrary.a and a header file called mylibrary.h this contains a function called myfunction(). I combined them with a cpp file (HelloWorldJNI.cpp) to make a new library named ...
1
vote
1
answer
79
views
How to monitor class loading and track origin jar using jvmti, jni or jvm function
I am making an antiCheating program for java game. I want to monitor the loading of all classes and find out which jar file it is loaded from, or is dynamically generated, so that I can calaulate hash ...
- 11
0
votes
2
answers
114
views
Run jar file that only exists in memory, larger than what a java byte array can hold
To give a quick overview of what my goal is, I've built an application that injects a DLL into a java process, which then proceeds to attempt to load and run a jar file from a remote host. Note that ...
- 37
0
votes
0
answers
186
views
Attempting to create a JVM in a process unexpectedly crashes due to OOM
I'm trying to debug an ODBC driver which is implemented partially in Java (using C++ & JNI).
We have a test tool which is used to run tests against the driver, but when it tries to load it, during ...
- 4,546
0
votes
1
answer
141
views
Unable to get provider com.google.android.gms.ads.MobileAdsInitProvider when using Admob with C++
I'm trying to add Admob advertising to a C++ Android game. The game uses NativeActivity and doesn't ship any Java code at all - it's all pure C++ and JNI code.
I've followed the Admob C++ instructions ...
- 1,327
2
votes
0
answers
61
views
How to define multiple classes at the same time using JNI [duplicate]
I have two classes that depend on each other in Java.
Example:
public class A {
public B b;
}
public class B{
public A a;
}
Now, I must define these two classes in JNI using env->...
- 29
0
votes
1
answer
181
views
How to define a resource with JNI
In JNI, I know that you can define a class using env->DefineClass. For example,
jclass klass = client->env->DefineClass(nullptr, classLoader, (const jbyte*) classBytes, (jsize) ...
- 29
2
votes
1
answer
831
views
How to apply Android R8 obfuscation to native code?
I'm developing an Android app that has to be obfuscated for security reasons. Some classes and fields that are obfuscated by R8 are used in my C++ code, so of course the obfuscation step breaks this ...
- 1,018
0
votes
0
answers
48
views
JNI call to FindClass returns null when run on a new thread [duplicate]
I am writing an Android appliction and am using JNI to call Java functions from C++. The following code works as expected, retrieving a reference to a static Java method and then calling it.
_JNIEnv *...
0
votes
0
answers
182
views
Calling JNI_CreateJavaVM just hangs
Just trying debug what wrong with harness code, which was compiled with command:
┌──(kali㉿kali)-[~/…/experimment/research/PoCs/android-afl-qemu]
└─$ export CC=/home/kali/Android/Sdk/ndk/22.1.7171670/...
- 25
0
votes
0
answers
54
views
JNI FindClass unable to find class from a packaged jar file
I am unable to use JNIs FindClass function to detect a class from a packaged jar file.
If I do not package the jar file (class files not within sub-folders) JNIs FindClass is successful, however I ...
- 81
0
votes
1
answer
89
views
How to call runOnUiThread in Android JNI C++
I have a method called "contactMSFServers" in Android JNI C++ which sends the post request to a API and get the JSON Returned and based on the JSON Success code i am showing toast but the ...
0
votes
1
answer
73
views
JNI NoClassDefFoundError while executing method in injected jar
I am getting NoClassDefFoundError when trying to inject a jar file into a running java process.
Jar file bytes:
static const unsigned char lib_bytes[] = {
0x50, 0x4b, 0x03, 0x04, 0x14, 0x00, ...
- 124
0
votes
0
answers
121
views
Why does FindLibrary return 0?
I'm trying to create a launcher for SAMP Android. Everything was going well until the integration of SAMP itself (build69). libsamp.so cannot find the address of the neighboring libGTASA.so library.
...
0
votes
0
answers
81
views
Why few of my symbols don't appear in my .so file? [duplicate]
I am creating an Android native application, where I have many cpp files and few kt files. With the use of cpp files, I am compiling static libraries which gives me .a extension files and as a whole I ...
- 253
1
vote
1
answer
193
views
How to use JNI without having to add jvm.dll location into Environment Variables Path
One way to make JNI work is to go into Environment Variables and add into User or System Path the folder where jvm.dll is located (.../bin/server). But this means that on a client machine, when your ...
user19405069
1
vote
0
answers
131
views
Unable to run android app with prebuilt native library
I have a library written in c++, and it is pre built by Androi NDK clang++ with Makefile command, like this:
libfoo.so:
$(CXX) -c -Wall -Werror -fpic ${SRC_PATH}foo.cpp
$(CXX) -shared -o ...
- 187
1
vote
1
answer
75
views
Constructing an object crashes jvm
Constructing an object crashes the jvm because the constructor is not found. The signature is correct and the constructor exists.
This is my new object code:
JavaObject(jclass klass, const char *...
- 124
0
votes
0
answers
427
views
Native Android Crash SIGNAL 11(SIGSEGV)
How to debug a signal 11 (SIGSEGV), code 1 (SEGV_MAPERR), fault addr 0x3634323064373235 in Android JNI?
I have tried using debugger to find out the root cause but the app is getting crashed randomly (...
- 45
1
vote
1
answer
1k
views
JNI DETECTED ERROR IN APPLICATION: Thread using JNIEnv* from different thread
When I try to call the function in the java class, I get the following error.
ava_vm_ext.cc:579] JNI DETECTED ERROR IN APPLICATION: thread Thread[21,tid=15479,Native,Thread*=0x7d932413a0,peer=...
- 423