program not compiling

[Diego Guimaraes]

Hi I’m trying to develop a simple Java App that calls twain

My c program is this but it is not compiling. I’m getting a bunch of errors like this “HANDLE does not name a type”, “LPVOID does not name a type”

#include <jni.h>
#include <stdio.h>
#include "twain.h"
#include "HelloWorld.h"

JNIEXPORT void JNICALL
Java_HelloWorld_print(JNIEnv *env, jobject obj) {
    printf("Hello World from C function!\n");
}

JNIEXPORT void JNICALL
Java_HelloWorld_scan(JNIEnv *env, jobject obj) {
    printf("Scanning")
}

My HelloWorld.h is

/* DO NOT EDIT THIS FILE - it is machine generated */
#include <jni.h>
/* Header for class HelloWorld */

#ifndef _Included_HelloWorld
#define _Included_HelloWorld
#ifdef __cplusplus
extern "C" {
#endif
/*
 * Class:     HelloWorld
 * Method:    print
 * Signature: ()V
 */
JNIEXPORT void JNICALL Java_HelloWorld_print
  (JNIEnv *, jobject);

/*
 * Class:     HelloWorld
 * Method:    scan
 * Signature: ()V
 */
JNIEXPORT void JNICALL Java_HelloWorld_scan
  (JNIEnv *, jobject);

#ifdef __cplusplus
}
#endif
#endif

I got the twain.h from this link https://www.codeproject.com/KB/audio-video/twaintest/twaintest_src.zip

I’m trying to generate a dll using this command from MinGW64

g++ -shared -I “C:\Program Files\Java\jdk1.8.0_101\include” -I “C:\Program Files\Java\jdk1.8.0_101\include\win32” HelloWorld.c -o HelloWorld.dll

[MarkM]

The twain.h file is for C/C++ only. There are Java libraries that interface to TWAIN. Searching for “java twain library” finds several…

[Author]

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