Java code example for sending UDP network text.

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/*
 Example how to send UDP text in Java.
  See also: sfk netlog.
 - copy this to a file netlog.java
 - javac netlog.java
  - run: dview -net
 under Linux/Mac: wine dview.exe -net -linux &
 - java netlog
*/
import java.io.*;
import java.net.*;
public class netlog
{
 public static DatagramSocket clSocket = null;
 public static InetAddress clAddress = null;
 public static int iClPort = -1;
 static int iClRequest = 1;
 public static void init(String sHost, int iPort) throws Throwable
 {
 clAddress = InetAddress.getByName(sHost);
 iClPort = iPort;
 clSocket = new DatagramSocket();
 }
 public static void log(String sTextIn) throws Throwable
 {
 String sText = sTextIn+"\n";
 // change all [red] to compact color codes \x1Fr
 byte[] abData1 = sText.getBytes();
 int iSize1 = abData1.length;
 byte[] abData2 = new byte[iSize1+100];
 // keep 100 bytes space for header
 int i2=100;
 for (int i1=0; i1<iSize1;)
 {
 if (abData1[i1]=='[') {
 i1++;
 if (i1>=iSize1)
 break;
 abData2[i2++] = (byte)0x1F;
 abData2[i2++] = abData1[i1++];
 while (i1<iSize1 && abData1[i1]!=']')
 i1++;
 if (i1<iSize1)
 i1++;
 } else {
 abData2[i2++] = abData1[i1++];
 }
 }
 int iTextSize = i2-100;
 // add sfktxt header before text
 String sHead = ":sfktxt:v100,req"+iClRequest+",cs1\n\n";
 iClRequest++;
 byte abHead[] = sHead.getBytes();
 int iHeadLen = abHead.length;
 for (int i=0; i<iHeadLen; i++)
 abData2[100-iHeadLen+i] = abHead[i];
 int iStartOff = 100-iHeadLen;
 int iFullSize = iHeadLen+iTextSize;
 DatagramPacket packet = new DatagramPacket(abData2,
 iStartOff, iFullSize, clAddress, iClPort);
 clSocket.send(packet);
 }
 public static void main(String args[]) throws Throwable
 {
 netlog.init("localhost", 21323);
 netlog.log("[Red]Foo[def] and [Blue]bar[def] went "
 +"to the [Green]zoo[def].");
 }
}

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