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
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