jni.h: no such file or directory
You have to add the JDK path to the include path, so the compiler knows the location of the file.
Windows:
/I "$(JAVA_HOME)\include" /I "$(JAVA_HOME)\include\win32"
Linux:
-I"${JAVA_HOME}/include" -I"${JAVA_HOME}/include/linux"
Mac:
-I"${JAVA_HOME}/include" -I"${JAVA_HOME}/include/darwin"