Port Scanner Java implementation

Program | port scan how to scan the local and remote port of computer system, monitor whether it is turned on or off in many applications, the following is a simple port scanner implemented in Java.

Source Code:



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/*
* Created on 2005-3-22
*
* TODO to change the template of this generated file go
* Window-preferences-java-code Style-code Templates
*/

/**
* @author Whandey Connect to Me:whandey@163.com
*
* TODO to change the template of this generated type comment go
* Window-preferences-java-code Style-code Templates
*/
Import java.io.*;
Import java.net.*;
Import java.util.*;


public class Socketport {

public static void Main (string[] args) {

String IP = "159.162.39.27";
string hostname = new string ();

try{//get the target IP address and hostname
InetAddress address = inetaddress.getbyname (IP);
SYSTEM.OUT.PRINTLN (address);
hostname = Address.gethostname ();
SYSTEM.OUT.PRINTLN (hostname);
}
catch (Unknownhostexception e)
{
System.out.println ("Could not find" + IP);

}


Try
{//creat the output file
PrintWriter fout = new PrintWriter (New FileWriter ("PortInf.txt"));
FOUT.PRINTLN ("Information of the Port on" + hostname + "computer");
Fout.println ();

Do ports scan
for (int nport = 25;nport < 30;++nport)
{
Try
{

Socket s = new socket (hostname,nport);
FOUT.PRINTLN ("The port" + Nport + "is open!");

Fout.println ("Connected to" + s.getinetaddress () + ' on port ' + s.getport () + "from port" + s.getlocalport () + "of" + S.getlocaladdress ());
Print the connected socket information
}

catch (IOException E)
{
FOUT.PRINTLN ("The port" + Nport + "is closed!");
}

}
Fout.close ();

}
catch (IOException e) {}

}
}