Jeeves - Sun's Java Server Applets/Servlets

Jeeves - Sun's Java Server

Applets/Servlets - Native Functions

Create a new Project in Visual C++ 4.0 (Dynamic Link Library) (we have called the project - sss so the dll will be sss.dll)
Copy the dll (sss.dll) into the Windows-System subdirectory.

The Files to be included in the Project will be

sss.c
sss.def
user32.lib

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

javai.lib
sss.c
sss.def
user32.lib
wsock32.lib

Click on Tools then Options, then Directories and set the include path to

c:\msdev\include
c:\java\include
c:\java\include\win32

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