We can check if a given port is free by trying to construct a ServerSocket with the port that needs to be checked:
import java.io.*;
import java.net.*;
public class CheckingIfPortIsFree
{
public static void main(String args[])
{
CheckingIfPortIsFree checkingIfPortIsFree = new CheckingIfPortIsFree();
checkingIfPortIsFree.proceed();
}
private void proceed()
{
int portToBeChecked = 4567;
boolean isPortFree;
try {
ServerSocket serverSocket = new ServerSocket(portToBeChecked);
isPortFree = true;
}
catch (IOException ioe)
{
isPortFree = false;
}
System.out.println("isPortFree: " + isPortFree);
}
}
/*
Expected output:
[root@mypc]# java CheckingIfPortIsFree
isPortFree: true
*/