I am a new guy here and have some problem I can't handle. I just write
a small class that hava a inner class. When the program running to the
line that I marked with **, it will call a exception like this: at
basicDomainNameLookUp.WellKnownPorts.<init>(WellKnownPorts.java:27).

Could somebody help me sovle this problem T_T, I really can't handle
it.Thanks.

public class WellKnownPorts
{
    /**
    * @param args
    */
    PortElement[] EKPs ;
    protected class PortElement
    {
        protected int portNum;
        protected String serviceName;
        protected String serviceAlias;

        protected void ProtElement ( int inputPortNum , String
inputServiceName , String inputServiceAlias )
        {
            portNum = inputPortNum;
            serviceName = inputServiceName;
            serviceAlias = inputServiceAlias;
        }
    }

    //Constractor
    public WellKnownPorts ()
    {
        EKPs = new PortElement[14];
**        EKPs[0].portNum = 7;                             **
        EKPs[0].serviceName = "echo";
        EKPs[0].serviceAlias = "echo";
        EKPs[1].portNum = 13;
        EKPs[1].serviceName = "DayTime";
        EKPs[1].serviceAlias = "DayTime";
        EKPs[2].portNum = 20;
        EKPs[2].serviceName = "File Transfer Protocol";
        EKPs[2].serviceAlias = "FTP";
        EKPs[3].portNum = 21;
        EKPs[3].serviceName = "File Transfer Protocol";
        EKPs[3].serviceAlias = "FTP";
        EKPs[4].portNum = 25;
        EKPs[4].serviceName = "Simple Mail Transfer Protocol";
        EKPs[4].serviceAlias = "SMTP";
        EKPs[5].portNum = 37;
        EKPs[5].serviceName = "Time";
        EKPs[5].serviceAlias = "Time";
        EKPs[6].portNum = 80;
        EKPs[6].serviceName = "HyperText Transfer Protocol";
        EKPs[6].serviceAlias = "HTTP";
        EKPs[7].portNum = 53;
        EKPs[7].serviceName = "Domain Name Service";
        EKPs[7].serviceAlias = "DNS";
        EKPs[8].portNum = 110;
        EKPs[8].serviceName = "Post Office Protocol version 3";
        EKPs[8].serviceAlias = "POP3";
        EKPs[9].portNum = 123;
        EKPs[9].serviceName = "Network Time Protocol ";
        EKPs[9].serviceAlias = "NTP";
        EKPs[10].portNum = 519;
        EKPs[10].serviceName = "utime";
        EKPs[10].serviceAlias = "utime";
        EKPs[11].portNum = 525;
        EKPs[11].serviceName = "timed timeserver";
        EKPs[11].serviceAlias = "timed timeserver";
        EKPs[12].portNum = 580;
        EKPs[12].serviceName = "Simple Network Time Protocol heartbeat";
        EKPs[12].serviceAlias = "SNTP";
        EKPs[13].portNum = 8889;
        EKPs[13].serviceName = "dbAnywhere";
        EKPs[13].serviceAlias = "dbAnywhere";
        }

}