{
  "dataSources":[
    {
      "xid":"DS_464401cf-d4f5-42e4-abb3-5cf0e7b43c99",
      "name":"UDP test",
      "enabled":true,
      "type":"META",
      "alarmLevels":{
        "SCRIPT_ERROR":"URGENT",
        "CONTEXT_POINT_DISABLED":"URGENT",
        "RESULT_TYPE_ERROR":"URGENT"
      },
      "purgeType":"YEARS",
      "editPermission":"",
      "purgeOverride":false,
      "purgePeriod":1
    }
  ],
  "dataPoints":[
    {
      "xid":"DP_02608a5a-1785-41b5-bc57-231b6823d810",
      "name":"UDP string sender",
      "enabled":true,
      "loggingType":"ON_CHANGE",
      "intervalLoggingPeriodType":"MINUTES",
      "intervalLoggingType":"INSTANT",
      "purgeType":"YEARS",
      "pointLocator":{
        "dataType":"ALPHANUMERIC",
        "updateEvent":"NONE",
        "contextUpdateEvent":"CONTEXT_UPDATE",
        "context":[
          {
            "varName":"input",
            "dataPointXid":"DP_d7f134b2-3940-4cc1-b9b3-2cf153342078",
            "updateContext":true
          }
        ],
        "logLevel":"NONE",
        "variableName":"point",
        "scriptPermissions":"superadmin",
        "executionDelaySeconds":0,
        "logCount":5,
        "logSize":1.0,
        "script":"var value = input.value;\nif (value == null) {\n    return value;\n}\n\nvar socket = new java.net.DatagramSocket();\ntry {\n    var address = java.net.InetAddress.getByName(\"10.55.55.10\");\n    var port = 1241;\n    \n    var valueBytes = value.getBytes(java.nio.charset.StandardCharsets.UTF_8);\n    var packet = new java.net.DatagramPacket(valueBytes, valueBytes.length, address, port);\n    \n    socket.send(packet);\n} finally {\n    socket.close();\n}\n\nreturn value;",
        "settable":false,
        "updateCronPattern":""
      },
      "eventDetectors":[
      ],
      "plotType":"STEP",
      "rollup":"NONE",
      "unit":"",
      "simplifyType":"NONE",
      "chartColour":"",
      "chartRenderer":{
        "type":"TABLE",
        "limit":10
      },
      "dataSourceXid":"DS_464401cf-d4f5-42e4-abb3-5cf0e7b43c99",
      "defaultCacheSize":1,
      "deviceName":"UDP sender",
      "discardExtremeValues":false,
      "discardHighLimit":1.7976931348623157E308,
      "discardLowLimit":-1.7976931348623157E308,
      "intervalLoggingPeriod":1,
      "intervalLoggingSampleWindowSize":0,
      "overrideIntervalLoggingSamples":false,
      "preventSetExtremeValues":false,
      "purgeOverride":false,
      "purgePeriod":1,
      "readPermission":"",
      "setExtremeHighLimit":1.7976931348623157E308,
      "setExtremeLowLimit":-1.7976931348623157E308,
      "setPermission":"",
      "tags":{
      },
      "textRenderer":{
        "type":"PLAIN",
        "useUnitAsSuffix":false,
        "suffix":""
      },
      "tolerance":0.0
    }
  ]
}

Actual script

var value = input.value;
if (value == null) {
    return value;
}

var socket = new java.net.DatagramSocket();
try {
    var address = java.net.InetAddress.getByName("10.55.55.10");
    var port = 1241;
    
    var valueBytes = value.getBytes(java.nio.charset.StandardCharsets.UTF_8);
    var packet = new java.net.DatagramPacket(valueBytes, valueBytes.length, address, port);
    
    socket.send(packet);
} finally {
    socket.close();
}

return value;

my old system use these code(c#), if you need to skip:

//your code here
private void opendoor(string DoorNumber)
        {
            string strDestinationIP = System.Configuration.ConfigurationSettings.AppSettings["DoorContoler"];
            string strMessage = string.Empty;
            if (DoorNumber.Equals("MainDoor"))
                strMessage = System.Configuration.ConfigurationSettings.AppSettings["MainDoorOpen"];           
            if (strMessage.Equals(string.Empty)) return;
            UdpClient udpClient = new UdpClient();
            IPAddress destinationIP = IPAddress.Parse(strDestinationIP);
            IPEndPoint destination = new IPEndPoint(destinationIP, 18001);
            byte[] message = HexStringToByteArray(strMessage);
            udpClient.Send(message, message.Length, destination);
            udpClient.Close();
        }

You would be able to instantiate a java.net.DatagramSocket in a script, for the most general ability to use UDP. But with details of why may come a better answer, as Jared suggests.

I want to use UDP to send data out.

Why? Presumably there is a service that you are trying to interact with? We need more information than just 'UDP'.