I am trying to follow this tutorial to build a JNI project from a Windows 10 machine with CYGWIN and MinGW installed:
I have managed to create the Java file HelloWorldJNI.java and generated the header file HelloWorldJNI.h.
The 'HelloWorldJNI.java' file:
public class HelloWorldJNI {
static {
System.loadLibrary("native");
}
public static void main(String[] args) {
new HelloWorldJNI().sayHello();
}
// Declare a native method sayHello() that receives no arguments and returns void
private native void sayHello();
}
The generated header file 'HelloWorldJNI.h':
/* DO NOT EDIT THIS FILE - it is machine generated */
#include <jni.h>
/* Header for class HelloWorldJNI */
#ifndef _Included_HelloWorldJNI
#define _Included_HelloWorldJNI
#ifdef __cplusplus
extern "C" {
#endif
/*
* Class: HelloWorldJNI
* Method: sayHello
* Signature: ()V
*/
JNIEXPORT void JNICALL Java_HelloWorldJNI_sayHello
(JNIEnv *, jobject);
#ifdef __cplusplus
}
#endif
#endif
The 'HelloWorldJNI.cpp' C++ file:
#include "HelloWorldJNI.h"
#include <stdio.h>
JNIEXPORT void JNICALL Java_HelloWorldJNI_sayHello(JNIEnv* env, jobject thisObject) {
printf("Hello World");
}
I attempted to use G++ compiler to compile the 'HelloWorldJNI.cpp' and received a bunch of errors:
C:\Users\Administrator\Desktop>g++ -c -I"C:\Program Files\Java\jdk-16.0.1\include" -I"C:\Program Files\Java\jdk-16.0.1\include\win32" HelloWorldJNI.cpp -o HelloWorldJNI.o
In file included from C:\Program Files\Java\jdk-16.0.1\include/jni.h:44,
from HelloWorldJNI.h:2,
from HelloWorldJNI.cpp:1:
C:\Program Files\Java\jdk-16.0.1\include\win32/jni_md.h:36:9: error: '__int64' does not name a type; did you mean '__int64_t'?
36 | typedef __int64 jlong;
| ^~~~~~~
| __int64_t
In file included from HelloWorldJNI.h:2,
from HelloWorldJNI.cpp:1:
C:\Program Files\Java\jdk-16.0.1\include/jni.h:125:5: error: 'jlong' does not name a type; did you mean 'ulong'?
125 | jlong j;
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:333:20: error: expected identifier before '*' token
333 | jlong (JNICALL *CallLongMethod)
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:333:21: warning: 'stdcall' attribute only applies to function types [-Wattributes]
333 | jlong (JNICALL *CallLongMethod)
| ^~~~~~~~~~~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:334:57: error: 'jlong' declared as function returning a function
334 | (JNIEnv *env, jobject obj, jmethodID methodID, ...);
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:335:20: error: expected identifier before '*' token
335 | jlong (JNICALL *CallLongMethodV)
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:335:21: warning: 'stdcall' attribute only applies to function types [-Wattributes]
335 | jlong (JNICALL *CallLongMethodV)
| ^~~~~~~~~~~~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:336:66: error: 'jlong' declared as function returning a function
336 | (JNIEnv *env, jobject obj, jmethodID methodID, va_list args);
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:337:20: error: expected identifier before '*' token
337 | jlong (JNICALL *CallLongMethodA)
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:337:21: warning: 'stdcall' attribute only applies to function types [-Wattributes]
337 | jlong (JNICALL *CallLongMethodA)
| ^~~~~~~~~~~~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:338:72: error: 'jlong' declared as function returning a function
338 | (JNIEnv *env, jobject obj, jmethodID methodID, const jvalue *args);
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:415:20: error: expected identifier before '*' token
415 | jlong (JNICALL *CallNonvirtualLongMethod)
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:415:21: warning: 'stdcall' attribute only applies to function types [-Wattributes]
415 | jlong (JNICALL *CallNonvirtualLongMethod)
| ^~~~~~~~~~~~~~~~~~~~~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:416:71: error: 'jlong' declared as function returning a function
416 | (JNIEnv *env, jobject obj, jclass clazz, jmethodID methodID, ...);
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:417:20: error: expected identifier before '*' token
417 | jlong (JNICALL *CallNonvirtualLongMethodV)
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:417:21: warning: 'stdcall' attribute only applies to function types [-Wattributes]
417 | jlong (JNICALL *CallNonvirtualLongMethodV)
| ^~~~~~~~~~~~~~~~~~~~~~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:419:20: error: 'jlong' declared as function returning a function
419 | va_list args);
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:420:20: error: expected identifier before '*' token
420 | jlong (JNICALL *CallNonvirtualLongMethodA)
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:420:21: warning: 'stdcall' attribute only applies to function types [-Wattributes]
420 | jlong (JNICALL *CallNonvirtualLongMethodA)
| ^~~~~~~~~~~~~~~~~~~~~~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:422:26: error: 'jlong' declared as function returning a function
422 | const jvalue *args);
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:466:20: error: expected identifier before '*' token
466 | jlong (JNICALL *GetLongField)
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:466:21: warning: 'stdcall' attribute only applies to function types [-Wattributes]
466 | jlong (JNICALL *GetLongField)
| ^~~~~~~~~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:467:50: error: 'jlong' declared as function returning a function
467 | (JNIEnv *env, jobject obj, jfieldID fieldID);
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:486:52: error: 'jlong' has not been declared
486 | (JNIEnv *env, jobject obj, jfieldID fieldID, jlong val);
| ^~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:537:20: error: expected identifier before '*' token
537 | jlong (JNICALL *CallStaticLongMethod)
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:537:21: warning: 'stdcall' attribute only applies to function types [-Wattributes]
537 | jlong (JNICALL *CallStaticLongMethod)
| ^~~~~~~~~~~~~~~~~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:538:58: error: 'jlong' declared as function returning a function
538 | (JNIEnv *env, jclass clazz, jmethodID methodID, ...);
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:539:20: error: expected identifier before '*' token
539 | jlong (JNICALL *CallStaticLongMethodV)
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:539:21: warning: 'stdcall' attribute only applies to function types [-Wattributes]
539 | jlong (JNICALL *CallStaticLongMethodV)
| ^~~~~~~~~~~~~~~~~~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:540:67: error: 'jlong' declared as function returning a function
540 | (JNIEnv *env, jclass clazz, jmethodID methodID, va_list args);
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:541:20: error: expected identifier before '*' token
541 | jlong (JNICALL *CallStaticLongMethodA)
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:541:21: warning: 'stdcall' attribute only applies to function types [-Wattributes]
541 | jlong (JNICALL *CallStaticLongMethodA)
| ^~~~~~~~~~~~~~~~~~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:542:73: error: 'jlong' declared as function returning a function
542 | (JNIEnv *env, jclass clazz, jmethodID methodID, const jvalue *args);
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:579:20: error: expected identifier before '*' token
579 | jlong (JNICALL *GetStaticLongField)
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:579:21: warning: 'stdcall' attribute only applies to function types [-Wattributes]
579 | jlong (JNICALL *GetStaticLongField)
| ^~~~~~~~~~~~~~~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:580:51: error: 'jlong' declared as function returning a function
580 | (JNIEnv *env, jclass clazz, jfieldID fieldID);
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:599:53: error: 'jlong' has not been declared
599 | (JNIEnv *env, jclass clazz, jfieldID fieldID, jlong value);
| ^~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:661:5: error: 'jlong' does not name a type; did you mean 'ulong'?
661 | jlong * (JNICALL *GetLongArrayElements)
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:679:39: error: 'jlong' has not been declared
679 | (JNIEnv *env, jlongArray array, jlong *elems, jint mode);
| ^~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:696:63: error: 'jlong' has not been declared
696 | (JNIEnv *env, jlongArray array, jsize start, jsize len, jlong *buf);
| ^~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:713:69: error: 'jlong' does not name a type; did you mean 'ulong'?
713 | (JNIEnv *env, jlongArray array, jsize start, jsize len, const jlong *buf);
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:757:37: error: 'jlong' has not been declared
757 | (JNIEnv* env, void* address, jlong capacity);
| ^~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:760:20: error: expected identifier before '*' token
760 | jlong (JNICALL *GetDirectBufferCapacity)
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:760:21: warning: 'stdcall' attribute only applies to function types [-Wattributes]
760 | jlong (JNICALL *GetDirectBufferCapacity)
| ^~~~~~~~~~~~~~~~~~~~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:761:33: error: 'jlong' declared as function returning a function
761 | (JNIEnv* env, jobject buf);
| ^
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1004:5: error: 'jlong' does not name a type; did you mean 'ulong'?
1004 | jlong CallLongMethod(jobject obj, jmethodID methodID, ...) {
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1012:5: error: 'jlong' does not name a type; did you mean 'ulong'?
1012 | jlong CallLongMethodV(jobject obj, jmethodID methodID,
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1016:5: error: 'jlong' does not name a type; did you mean 'ulong'?
1016 | jlong CallLongMethodA(jobject obj, jmethodID methodID,
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1196:5: error: 'jlong' does not name a type; did you mean 'ulong'?
1196 | jlong CallNonvirtualLongMethod(jobject obj, jclass clazz,
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1206:5: error: 'jlong' does not name a type; did you mean 'ulong'?
1206 | jlong CallNonvirtualLongMethodV(jobject obj, jclass clazz,
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1211:5: error: 'jlong' does not name a type; did you mean 'ulong'?
1211 | jlong CallNonvirtualLongMethodA(jobject obj, jclass clazz,
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1304:5: error: 'jlong' does not name a type; did you mean 'ulong'?
1304 | jlong GetLongField(jobject obj, jfieldID fieldID) {
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1338:23: error: 'jlong' has not been declared
1338 | jlong val) {
| ^~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1463:5: error: 'jlong' does not name a type; did you mean 'ulong'?
1463 | jlong CallStaticLongMethod(jclass clazz,
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1472:5: error: 'jlong' does not name a type; did you mean 'ulong'?
1472 | jlong CallStaticLongMethodV(jclass clazz,
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1476:5: error: 'jlong' does not name a type; did you mean 'ulong'?
1476 | jlong CallStaticLongMethodA(jclass clazz,
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1554:5: error: 'jlong' does not name a type; did you mean 'ulong'?
1554 | jlong GetStaticLongField(jclass clazz, jfieldID fieldID) {
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1589:25: error: 'jlong' has not been declared
1589 | jlong value) {
| ^~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1683:5: error: 'jlong' does not name a type; did you mean 'ulong'?
1683 | jlong * GetLongArrayElements(jlongArray array, jboolean *isCopy) {
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1719:35: error: 'jlong' has not been declared
1719 | jlong *elems,
| ^~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1755:53: error: 'jlong' has not been declared
1755 | jsize start, jsize len, jlong *buf) {
| ^~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1788:35: error: 'jlong' does not name a type; did you mean 'ulong'?
1788 | const jlong *buf) {
| ^~~~~
| ulong
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1851:48: error: 'jlong' has not been declared
1851 | jobject NewDirectByteBuffer(void* address, jlong capacity) {
| ^~~~~
C:\Program Files\Java\jdk-16.0.1\include/jni.h:1857:5: error: 'jlong' does not name a type; did you mean 'ulong'?
1857 | jlong GetDirectBufferCapacity(jobject buf) {
| ^~~~~
| ulong
How do I fix the issue with the compilation ?
