JNI 无法在 NetBeans 上检测到 __int64 [英] JNI cannot detect __int64 on NetBeans

问题描述

我正在尝试编译一个本地库以从 java 中使用它(使用 JNI).我已按照本教程进行操作:https://cnd.netbeans.org/docs/jni/beginning-jni-win.html

I'm trying to compile a native library to use it from java (with JNI). I have followed this tutorial: https://cnd.netbeans.org/docs/jni/beginning-jni-win.html

当我尝试编译时，我有这个错误(见第 4 行):

When I try to compile, I have this error (see line 4):

[...]
In file included from ../../Progra~2/Java/jdk1.8.0_91/include/jni.h:45:0,
                 from HelloWorldNative.h:3,
                 from HelloWorldNative.c:6:
../../Progra~2/Java/jdk1.8.0_91/include/win32/jni_md.h:34:9: error: unknown type name '__int64'
 typedef __int64 jlong;
         ^
nbproject/Makefile-Debug.mk:66: recipe for target 'build/Debug/Cygwin-Windows/HelloWorldNative.o' failed
[...]

我可以在 #include <jni.h> 之前添加 typedef long long __int64 来解决此错误，但我认为我正在做某事错了.

I can solve this error adding a typedef long long __int64 before the #include <jni.h> but I assume that there is something that I'm doing wrong.

代码如下:

头文件:

/* DO NOT EDIT THIS FILE - it is machine generated */
typedef long long __int64; // <============ Why do I need to do this?
#include <jni.h>
/* Header for class helloworld_Main */

#ifndef _Included_helloworld_Main
#define _Included_helloworld_Main
#ifdef __cplusplus
extern "C" {
#endif
/*
 * Class:     helloworld_Main
 * Method:    nativePrint
 * Signature: ()V
 */
JNIEXPORT void JNICALL Java_helloworld_Main_nativePrint
  (JNIEnv *, jobject);

#ifdef __cplusplus
}
#endif
#endif

源文件:

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
#include "HelloWorldNative.h"

JNIEXPORT void JNICALL Java_helloworld_Main_nativePrint
  (JNIEnv *env, jobject _this){

}

推荐答案

__int64 是 Visual Studio 具体类型

__int64 is Visual Studio specific type

使用标准类型，例如 int64_t 或 uint64_t.在 <cstdint> 中定义 C++，在 中定义 C.

Use standard types like int64_t or uint64_t. Defined in <cstdint> for C++ and in <stdint.h> for C.

您的错误的确切解决方案可以在 JNI 常见问题中找到:

Exact solution to your error can be found in JNI faq:

http://www.oracle.com/technetwork/java/jni-j2sdk-faq-141732.html

Your compiler might not like __int64 in jni_md.h. You should fix this by adding:
    #ifdef FOOBAR_COMPILER
    #define __int64 signed_64_bit_type
    #endif
where signed_64_bit_type is the name of the signed 64 bit type supported by your compiler.

所以你应该使用:

#define __int64 long long

或:

#include <stdint.h>
#define __int64 int64_t

这与您最初所做的非常相似

which is quite similar to what you have initially done

这篇关于JNI 无法在 NetBeans 上检测到 __int64的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！