change Semantics of Client AutoConnect.searchServer.

* now returns an optional
* uses multiple trys.

client/src/main/kotlin/org/hso/texturesyncclient/controller/net/AutoConnect.kt

@@ -1,48 +1,60 @@
 package org.hso.texturesyncclient.controller.net
 
 import java.io.IOException
-import java.lang.Exception
 import java.net.DatagramPacket
 import java.net.DatagramSocket
 import java.net.InetAddress
 
-class AutoConnect {
-    private constructor() {}
+class AutoConnect private constructor() {
 
     companion object {
         @Throws(IOException::class)
-        fun search_server(mulicastAddr: String = "ff02::dd42:c0fe", port: Int = 10796, timeoutMs : Int = 4000): Connection {
+        fun searchServer(
+            mulicastAddr: String = "ff02::dd42:c0fe",
+            port: Int = 10796,
+            timeoutMs: Int = 400,
+            trys: Int = 10
+        ): Connection? {
             val sock = DatagramSocket()
             try {
                 sock.soTimeout = timeoutMs
 
-                val bytes = "TextureSync".toByteArray()
+                for (i in 0..trys) {
+                    val bytes = "TextureSync".toByteArray()
 
-                sock.send(
-                    DatagramPacket(
-                        bytes,
-                        0,
-                        bytes.size,
-                        InetAddress.getByName(mulicastAddr),
-                        port
+                    sock.send(
+                        DatagramPacket(
+                            bytes,
+                            0,
+                            bytes.size,
+                            InetAddress.getByName(mulicastAddr),
+                            port
+                        )
                     )
-                )
 
-                // Response is PortNum in BE
-                val portData = ByteArray(2)
-                val response = DatagramPacket(portData, portData.size)
+                    // Response is PortNum in BE
+                    val portData = ByteArray(2)
+                    val response = DatagramPacket(portData, portData.size)
 
-                sock.receive(response)
+                    try {
+                        sock.receive(response)
 
-                // 2-Byte BE to Port Number
-                val port = (portData[0].toInt().shl(8)).or(portData[1].toInt())
+                        // 2-Byte BE to Port Number
+                        val serverPort = (portData[0].toInt().shl(8)).or(portData[1].toInt())
 
-                return Connection(response.address, port)
-            } catch ( e : Exception) {
+                        return Connection(response.address, serverPort)
+                    } catch (e: IOException) {
+                        // Timed out
+                        // NOP
+                    }
+                }
+            } catch (e: Exception) {
                 throw e
             } finally {
                 sock.close()
             }
+
+            return null
         }
     }
 }