Jeeves - Sun's Java Server

Applets/Servlets - Native Functions

The Files to be included in the Project will be
To learn the basics of native functions refer to our native tutorial on the Java Page
Program 1

I Java Applet - Simple Program

aaa.java 
class aaa

{      public static void main(String s[])

       {      bbb a;

              System.out.println("Start");

              a = new bbb();

              System.out.println("Before xx");

               a.xx();

               System.out.println("After xx");

         }

}

	

class bbb

{      public native void xx();

       public bbb()

       {

            System.out.println("in bbb");

            System.loadLibrary("sss");

        }

}
sss.c 
#include <windows.h>
void *Java_bbb_xx_stub(void * p)

{       MessageBox(0,"Hi","Hi",0);

        return p;

}
sss.def 
LIBRARY     sss

EXPORTS

        Java_bbb_xx_stub

I Servlet Simple Program

s.java 
import java.io.*;

import java.servlet.*;



public class s extends Servlet

{



public void service(ServletRequest req,ServletResponse res) throws IOException

{

        bbb a;

        res.setContentType("text/html");

        res.writeHeaders();

        PrintStream out =new PrintStream(res.getOutputStream());

        out.println("Start");

        a=new bbb();

        out.println("Before xx");

        a.xx();

        out.println("After xx");

}

}

class bbb

{      public native void xx();

       public bbb()

       {

            System.loadLibrary("sss");

       }

}
sss.c 
#include <windows.h>
void *Java_bbb_xx_stub(void * p)

{       MessageBox(0,"Hi","Hi",0);

        return p;

}
sss.def 
LIBRARY     sss

EXPORTS

        Java_bbb_xx_stub
Program 2

II Java Applet - Ping Program

aaa.java 
class aaa

{      public static void main(String s[])

       {      bbb a;

              System.out.println("Start");



              a = new bbb();

              System.out.println("Before xx");

		

               a.xx();

               System.out.println("After xx");

         }

}

	

class bbb

{      public native void xx();

       public bbb()

       {

            System.out.println("in bbb");

            System.loadLibrary("sss");

        }

}
sss.def 
LIBRARY     sss

EXPORTS

        Java_bbb_xx_stub
sss.c 
#include <windows.h>


struct o

{

        unsigned char Ttl,Tos,Flags,OptionsSize,*OptionsData;

};

struct

{

        DWORD Address;

        unsigned long  Status,RoundTripTime;

        unsigned short DataSize,Reserved;

        void *Data;                  

        struct o  Options;

} E;



HANDLE hIP;WSADATA wsa;HANDLE hIcmp;DWORD *dwIPAddr;struct hostent *phostent;

DWORD d;char aa[100];struct o I;



HANDLE ( WINAPI *pIcmpCreateFile )( VOID );

BOOL ( WINAPI *pIcmpCloseHandle )( HANDLE );

DWORD (WINAPI *pIcmpSendEcho)(HANDLE,DWORD,LPVOID,WORD,LPVOID,

                                        LPVOID,DWORD,DWORD);





void *Java_bbb_xx_stub(void * p)

{  

    hIcmp = LoadLibrary( "ICMP.DLL" );

        WSAStartup( 0x0101, &wsa );

		MessageBox(0,"In Java_bb_xx_stub","hi",0);

        phostent = gethostbyname( "www.microsoft.com");

        dwIPAddr = (DWORD *)( *phostent->h_addr_list );

        

        pIcmpCreateFile=GetProcAddress( hIcmp,"IcmpCreateFile");

        pIcmpCloseHandle=GetProcAddress( hIcmp,"IcmpCloseHandle");

        pIcmpSendEcho =GetProcAddress( hIcmp,"IcmpSendEcho" );



        hIP = pIcmpCreateFile();

        I.Ttl=6;

        pIcmpSendEcho(hIP,*dwIPAddr,0,0,&I,&E,sizeof(E),8000 );

        d=E.Address;

        phostent = gethostbyaddr((char *)&d,4,PF_INET);

        sprintf(aa,"gethostbyaddr %p",phostent );

        MessageBox(0,aa,aa,0);

        if ( phostent  != 0 )

                MessageBox(0,phostent->h_name,"hi",0);

        wsprintf(aa,"RTT: %dms,  TTL: %d",E.RoundTripTime,E.Options.Ttl );

        MessageBox(0,aa,"hi",0);

        pIcmpCloseHandle( hIP );

        FreeLibrary( hIcmp );

        WSACleanup();                                       

       return p;

}

II Servlet -Ping Program

s.java 
import java.io.*;

import java.servlet.*;



public class s extends Servlet

{



public void service(ServletRequest req,ServletResponse res) throws IOException

{

        bbb a;

        res.setContentType("text/html");

        res.writeHeaders();

        PrintStream out =new PrintStream(res.getOutputStream());

        out.println("Start");

        a=new bbb();

        a.xx();

        out.println("Hop No...." + a.ctr + "<p>");

        out.println("Computer... : " + a.str + "<p>");

}



}





class bbb

{       int ctr;

        String str;

        public native void xx();

	bbb()

        {

		System.loadLibrary("sss");

	}



}
The files in the project will be
Click on Tools then Options, then Directories and set the include path to

sss.c 

#include <StubPreamble.h>
#include <fcntl.h>
#include <javaString.h>
struct o

{

        unsigned char Ttl,Tos,Flags,OptionsSize,*OptionsData;

};

struct

{

        DWORD Address;

        unsigned long  Status,RoundTripTime;

        unsigned short DataSize,Reserved;

        void *Data;                  

        struct o  Options;

} E;



HANDLE hIP;WSADATA wsa;HANDLE hIcmp;DWORD *dwIPAddr;struct hostent *phostent;

DWORD d;char aa[100],bb[100];struct o I;



HANDLE ( WINAPI *pIcmpCreateFile )( VOID );

BOOL ( WINAPI *pIcmpCloseHandle )( HANDLE );

DWORD (WINAPI *pIcmpSendEcho)(HANDLE,DWORD,LPVOID,WORD,LPVOID,

                                        LPVOID,DWORD,DWORD);





struct zzz

{

    long f;    

	struct Hjava_lang_String * p;

        

};



struct yyy

{

        struct zzz * oo;

        void * m;

};



long bbb_xx(struct yyy * t)

{

        char u[1000];

        hIcmp = LoadLibrary( "ICMP.DLL" );

        WSAStartup( 0x0101, &wsa );



        phostent = gethostbyname( "www.microsoft.com");

        dwIPAddr = (DWORD *)( *phostent->h_addr_list );

    

        pIcmpCreateFile=GetProcAddress( hIcmp,"IcmpCreateFile");

        pIcmpCloseHandle=GetProcAddress( hIcmp,"IcmpCloseHandle");

        pIcmpSendEcho =GetProcAddress( hIcmp,"IcmpSendEcho" );



        hIP = pIcmpCreateFile();

        I.Ttl=6;

        pIcmpSendEcho(hIP,*dwIPAddr,0,0,&I,&E,sizeof(E),8000 );

        d=E.Address;

        phostent = gethostbyaddr((char *)&d,4,PF_INET);

        sprintf(aa,"gethostbyaddr %p",phostent );

        if ( phostent  != 0 )

                strcpy(aa,phostent->h_name);

		else

				strcpy(aa,"\0");

		sprintf(bb,"...RTT: %dms,  TTL: %d",E.RoundTripTime,E.Options.Ttl );

        strcat(aa,bb);

        MessageBox(0,aa,"hi",0);

        pIcmpCloseHandle( hIP );

        FreeLibrary( hIcmp );

        WSACleanup();                                       



        strcpy(u,aa);

                                t->oo->f = I.Ttl;

                t->oo->p=makeJavaString(u,strlen(u));

        return 1;

}





stack_item * Java_bbb_xx_stub(stack_item * z, void *e)

{

        bbb_xx(z->p);

        return z + 1; 

}

III Servlet - Ping Program - HTML Form

a1.html 
<html>
<form action=/servlet/s method=get>
Host Computer:(www.neca.com) <br>
<input type=text name=a><p>
Hop Number :<br>
<input type=text size=5 name=b><p>
<input type=submit value="Click..."><p>
</form>
</html>
s.java 
import java.io.*;

import java.servlet.*;



public class s extends Servlet

{

int aa,bb;

public void service(ServletRequest req,ServletResponse res) throws IOException

{



        String aa = req.getQueryParameter("a");

        String bb = req.getQueryParameter("b");

        res.setContentType("text/html");

        res.writeHeaders();

        PrintStream out =new PrintStream(res.getOutputStream());

        out.println("Computer... : " +aa+ "<p>");

        out.println("Hop No...." + bb + "<p>");

        bbb a;

        a=new bbb();

        a.str1=aa;

        a.str2= bb;

        a.xx();

        out.println("Result ..:" + a.str+ "<p>");

}

}





class bbb

{       String str,str1,str2;

        public native void xx();

	bbb()

        {

		System.loadLibrary("sss");

	}



}
sss.c 
#include <StubPreamble.h>
#include <fcntl.h>
#include <javaString.h>
struct o

{

        unsigned char Ttl,Tos,Flags,OptionsSize,*OptionsData;

};

struct

{

        DWORD Address;

        unsigned long  Status,RoundTripTime;

        unsigned short DataSize,Reserved;

        void *Data;                  

        struct o  Options;

} E;



HANDLE hIP;WSADATA wsa;HANDLE hIcmp;DWORD *dwIPAddr;struct hostent *phostent;

DWORD d;char aa[100],bb[100];struct o I;



HANDLE ( WINAPI *pIcmpCreateFile )( VOID );

BOOL ( WINAPI *pIcmpCloseHandle )( HANDLE );

DWORD (WINAPI *pIcmpSendEcho)(HANDLE,DWORD,LPVOID,WORD,LPVOID,

                                        LPVOID,DWORD,DWORD);





struct zzz

{

        struct Hjava_lang_String * p;

        struct Hjava_lang_String * p1;

        struct Hjava_lang_String * p2;

};



struct yyy

{

        struct zzz * oo;

        void * m;

};



long bbb_xx(struct yyy * t)

{

        char u[1000],u1[1000],u2[1000];

        int ii;

   

        javaString2CString(t->oo->p1,u1,1000);

       javaString2CString(t->oo->p2,u2,1000);

       ii=atoi(u2);

		MessageBox(0,u1,u2,0);

        hIcmp = LoadLibrary( "ICMP.DLL" );

        WSAStartup( 0x0101, &wsa );



        phostent = gethostbyname(u1);

        dwIPAddr = (DWORD *)( *phostent->h_addr_list );

    

        pIcmpCreateFile=GetProcAddress( hIcmp,"IcmpCreateFile");

        pIcmpCloseHandle=GetProcAddress( hIcmp,"IcmpCloseHandle");

        pIcmpSendEcho =GetProcAddress( hIcmp,"IcmpSendEcho" );



        hIP = pIcmpCreateFile();

        I.Ttl=ii;

        pIcmpSendEcho(hIP,*dwIPAddr,0,0,&I,&E,sizeof(E),8000 );

        d=E.Address;

        phostent = gethostbyaddr((char *)&d,4,PF_INET);

        sprintf(aa,"gethostbyaddr %p",phostent );

        if ( phostent  != 0 )

                strcpy(aa,phostent->h_name);

        else

                strcpy(aa,"\0");

        sprintf(bb,"...RTT: %dms,  TTL: %d",E.RoundTripTime,E.Options.Ttl );

        strcat(aa,bb);

        MessageBox(0,aa,"hi",0);

        pIcmpCloseHandle( hIP );

        FreeLibrary( hIcmp );

        WSACleanup();                                       



        strcpy(u,aa);

        t->oo->p=makeJavaString(u,strlen(u));

        return 1;

}





stack_item * Java_bbb_xx_stub(stack_item * z, void *e)

{

        bbb_xx(z->p);

        return z + 1; 

}

The above tutorial is a joint effort of

Mr. Vijay Mukhi
Ms. Sonal Kotecha

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Vijay Mukhi's Computer Institute
VMCI, B-13, Everest Building, Tardeo, Bombay 400 034, India
E-mail:vmukhi@giasbm01.vsnl.net.in Tel : 91-22-496 4335 /6/7/8/9 Fax : 91-22-307 28 59
http://www.neca.com/~vmis