JNI MinGW Tutorial x64 Windows

JNI Steps

########## GNU MinGW JNI Tutorial Windows x64 ############

##. Copy jni.h jni_md.h to MinGW include Directory


 --- JniApp.java ----

public class JniApp{
    public native int factorial(int number);
    
    public static void main(String[] args){
        JniApp ja = new JniApp();
        int f = ja.factorial(5);
        System.out.println("Factorial of 5 is : " + f);
    }
    
    /// Add Later if Not Works
    static
    {
  	System.loadLibrary("Factorial");
    }
}


##. javac JniApp.java
##. javah -jni JniApp

##. JniApp.h header file contents :

  JNIEXPORT jint JNICALL Java_JniApp_factorial
  (JNIEnv *, jobject, jint);
  
  change it to JniApp.c by following:
  
  ----- Factorial.c -------
  
    #include <stdio.h>
	#include "jni.h"
    #include "JniApp.h"

	JNIEXPORT jint JNICALL Java_JniApp_factorial
	(JNIEnv *env, jobject obj, jint num)
	{
		int fact = 1;
		while(num > 0){
			fact *= num;
			num--;        
		}
	}

##. gcc -c Factorial.c 

##. gcc -shared -o Factorial.dll Factorial.o

##. Javac JniApp.java

	--- JniApp.java ----

	public class JniApp{
		public native int factorial(int number);
		
		public static void main(String[] args){
			JniApp ja = new JniApp();
			int f = ja.factorial(5);
			System.out.println("Factorial of 5 is : " + f);
		}
		static{
			System.loadLibrary("Factorial");
		}
		
	}
	
##. java JniApp

JNI-Shell.cmd

call javac JniApp.java
call javah -jni JniApp
call gcc -c Factorial.c
call gcc -shared -o Factorial.dll Factorial.o
call Javac JniApp.java
call java JniApp

good work !!