CMakeLists.txt

cmake_minimum_required(VERSION 3.13 FATAL_ERROR)

project(jni-lib VERSION 0.1.0 LANGUAGES CXX)

set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_CXX_EXTENSIONS OFF)

include(GNUInstallDirs)
set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_LIBDIR})
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_LIBDIR})
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_BINDIR})

# jvm
find_package(Java REQUIRED)
# https://stackoverflow.com/questions/51047978/cmake-could-not-find-jni
set(JAVA_AWT_LIBRARY NotNeeded)
set(JAVA_JVM_LIBRARY NotNeeded)
find_package(JNI REQUIRED)

include_directories(${JNI_INCLUDE_DIRS})

# force off-tree build
if(${CMAKE_SOURCE_DIR} STREQUAL ${CMAKE_BINARY_DIR})
  message(FATAL_ERROR "CMake generation is not allowed within the source directory!
  Remove the CMakeCache.txt file and try again from another folder, e.g.:
    mkdir build && cd build
    cmake ..
  ")
endif()

# default to Release build
if(NOT CMAKE_BUILD_TYPE)
  set(CMAKE_BUILD_TYPE Release CACHE STRING
      "Choose the type of build, options are: None Debug Release RelWithDebInfo MinSizeRel."
      FORCE)
endif()

include_directories(src/main/include)
add_subdirectory(src/main/cpp)