C :: How To Generate DLL File In Eclipse

I just re-installed my OS some days ago,which contained Visual Studio.But I don't want to use the VS any more(at least in my computer) as the interminable installing process.Then I take Eclipse as my C/C++ IDE by MinGW and CDT. My Java program need to load an DLL file which wrote by C.But when I generating the DLL file,I got some errors.It seems that the compiler cannot find the header files. By the way,I just want to implement the hello-world program in C and invoke it in the Java program.This is my Java testing program:

Code:

public class HelloWorld{ public native void printHelloWorld();
static{
System.loadLibrary("hello");
}
public static void main(String[] args){
new HelloWorld().printHelloWorld();
}
}

And this is the header file generating by "javah HelloWorld":

Code:

/* 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

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