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InetAddress errors

CrazyOne asked
Last Modified: 2014-05-01
I have an array list of string arrays. In the string arrays is the IP address extracted from  a Datagram sent by a host. The value that is put into the string array is precisely the same as it arrived from the Datagram. However when I try to use the IP address from the string array I get an error.

for (int i = 0; i < listOfArrays.size(); i++) {
         String[] host = listOfArrays.get(i);
         System.out.println("ARRAY: " + host[0]);
         InetAddress hostAddr = InetAddress.getByName(host[0] );
         udpPcktSend = new DatagramPacket(bufYESSS, bufYESSS.length, hostAddr, Integer.parseInt(host[hPort].toString()));

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With this error happening on this line of code
InetAddress hostAddr = InetAddress.getByName(host[0] );
Exception in thread "main" java.net.UnknownHostException: "/"
      at java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method)
      at java.net.InetAddress$1.lookupAllHostAddr(InetAddress.java:901)
      at java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1293)
      at java.net.InetAddress.getAllByName0(InetAddress.java:1246)
      at java.net.InetAddress.getAllByName(InetAddress.java:1162)
      at java.net.InetAddress.getAllByName(InetAddress.java:1098)
      at java.net.InetAddress.getByName(InetAddress.java:1048)
      at CSMA_CH_SS.main(CSMA_CH_SS.java:102)

It worked yesterday now it is not. Now if I do the following and use the variable "address" it works fine and the IP address in both cases is the same.

udpPacketRcv = new DatagramPacket(buf, buf.length);
         fromClient = new String(udpPacketRcv.getData(), 0, udpPacketRcv.getLength()); 
         address = udpPacketRcv.getAddress();

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