Java – CMake could not find JNI

I created a new Android Studio project that supports C++, but didn’t add anything to it. The project is built, compiled, and run using CMake. Then, I added the following two lines of code to the CMakeLists.txt at the bottom of the file, and I got the CMake build error.

find_package(Java COMPONENTS Development)       # Line 47
find_package(JNI REQUIRED)                      # Line 48

This is the error I encountered while building the project

-- Found Java: /usr/lib/jvm/java-10-oracle/bin/java (found version "10.0.1") found components:  Development 
-- Configuring incomplete, errors occurred!
CMake Error at /home/xxxxx/Android/Sdk/cmake/3.6.4111459/share/cmake-3.6/Modules/FindPackageHandleStandardArgs.cmake:148 (message):
  Could NOT find JNI (missing: JAVA_AWT_LIBRARY JAVA_JVM_LIBRARY
See also "/home/xxxxx/AndroidStudioProjects/MyApplication/app/.externalNativeBuild/cmake/release/x86_64/CMakeFiles/CMakeOutput.log".
  JAVA_INCLUDE_PATH2 JAVA_AWT_INCLUDE_PATH)
Call Stack (most recent call first):
  /home/xxxxxx/Android/Sdk/cmake/3.6.4111459/share/cmake-3.6/Modules/FindPackageHandleStandardArgs.cmake:388 (_FPHSA_FAILURE_MESSAGE)
  /home/xxxxxx/Android/Sdk/cmake/3.6.4111459/share/cmake-3.6/Modules/FindJNI.cmake:314 (FIND_PACKAGE_HANDLE_STANDARD_ARGS)
  CMakeLists.txt:48 (find_package)
External native generate JSON release: JSON generation completed with problems

CMake runs when invoked from the command line, but fails in Android Studio for some reason, I’m not sure why.

Edit 1

This is the CMakeOutput.log file

Edit 2

That’s all there is in the CMakeLists.txt file. It is compiled in cmd using the command cmake.

cmake_minimum_required(VERSION 3.4.1)

find_package(Java COMPONENTS Development)
find_package(JNI REQUIRED)

This is the command output

    E:\Users\xxxxx\AndroidStudioProjects\MyApplication\app\build>cmake ..
-- Configuring done
-- Generating done
-- Build files have been written to: E:/Users/xxxxx/AndroidStudioProjects/MyApplication/app/build

When I try to compile using gradle to add it in Android Studio, I get the following error on Windows 10 Pro 64-bit

Microsoft Windows [Version 10.0.17134.112]
(c) 2018 Microsoft Corporation. All rights reserved.

E:\Users\xxxxx\AndroidStudioProjects\MyApplication>gradlew build --stacktrace

> Task :app:generateJsonModelDebug 
External native generate JSON debug: starting JSON generation
External native generate JSON debug: using platform version 24 for ABI ARMEABI_V7A and min SDK version 24
External native generate JSON debug: noticing that build file 'E:\Users\xxxxx\AndroidStudioProjects\MyApplication\app\CMakeLists.txt' is out of date with respect to E: \Users\xxxxx\AndroidStudioProjects\MyApplication\app\.extern
alNativeBuild\cmake\debug\armeabi-v7a\android_gradle_build.json
External native generate JSON debug: rebuilding JSON E:\Users\xxxxx\AndroidStudioProjects\MyApplication\app\.externalNativeBuild\cmake\debug\armeabi-v7a\android_gradle_ build.json due to:
External native generate JSON debug: - a dependent build file changed
External native generate JSON debug: keeping json folder 'E:\Users\xxxxx\AndroidStudioProjects\MyApplication\app\.externalNativeBuild\cmake\debug\armeabi-v7a' but regenerating project
External native generate JSON debug: executing cmake Executable : E:\Android\SDK\cmake\3.6.4111459\bin\cmake.exe
arguments :
-HE:\Users\xxxxx\AndroidStudioProjects\MyApplication\app
-BE:\Users\xxxxx\AndroidStudioProjects\MyApplication\app\.externalNativeBuild\cmake\debug\armeabi-v7a
-DANDROID_ABI=armeabi-v7a
-DANDROID_PLATFORM=android-24
-DCMAKE_LIBRARY_OUTPUT_DIRECTORY=E:\Users\xxxxx\AndroidStudioProjects\MyApplication\app\build\intermediates\cmake\debug\obj\armeabi-v7a
-DCMAKE_BUILD_TYPE=Debug
-DANDROID_NDK=E:\Android\SDK\ndk-bundle
-DCMAKE_CXX_FLAGS=
-DCMAKE_TOOLCHAIN_FILE=E:\Android\SDK\ndk-bundle\build\cmake\android.toolchain.cmake
-DCMAKE_MAKE_PROGRAM=E:\Android\SDK\cmake\3.6.4111459\bin\ninja.exe
-GAndroid Gradle - Ninja
jvmArgs :

CMake Error at E:/Android/SDK/cmake/3.6.4111459/share/cmake-3.6/Modules/FindPackageHandleStandardArgs.cmake:148 (message):
  Could NOT find JNI (missing: JAVA_AWT_LIBRARY JAVA_JVM_LIBRARY
  JAVA_INCLUDE_PATH2 JAVA_AWT_INCLUDE_PATH)
Call Stack (most recent call first):
  E:/Android/SDK/cmake/3.6.4111459/share/cmake-3.6/Modules/FindPackageHandleStandardArgs.cmake:388 (_FPHSA_FAILURE_MESSAGE)
  E:/Android/SDK/cmake/3.6.4111459/share/cmake-3.6/Modules/FindJNI.cmake:314 (FIND_PACKAGE_HANDLE_STANDARD_ARGS)
  CMakeLists.txt:4 (find_package)
-- Configuring incomplete, errors occurred!
See also "E:/Users/xxxxx/AndroidStudioProjects/MyApplication/app/.externalNativeBuild/cmake/debug/armeabi-v7a/CMakeFiles/CMakeOutput.log".

Could NOT find JNI (missing: JAVA_AWT_LIBRARY JAVA_JVM_LIBRARY

Solved

sudo apt-get install -y openjdk-8-jdk
sudo apt-get install -y default-jdk
export JAVA_HOME=/usr/lib/jvm/java-8-openjdk-amd64