added first test case towards SwissTiming SailMaster connectivity

java/com.sap.sailing.domain.swisstimingadapter/src/com/sap/sailing/domain/swisstimingadapter/impl/SailMasterConnector.java

@@ -0,0 +1,31 @@
+package com.sap.sailing.domain.swisstimingadapter.impl;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.net.Socket;
+import java.net.UnknownHostException;
+
+public class SailMasterConnector extends SailMasterTransceiver {
+    private final String host;
+    private final int port;
+    private Socket socket;
+    
+    public SailMasterConnector(String host, int port) {
+        super();
+        this.host = host;
+        this.port = port;
+    }
+    
+    public String sendRequestAndGetResponse(String requestMessage) throws UnknownHostException, IOException {
+        ensureSocketIsOpen();
+        OutputStream os = socket.getOutputStream();
+        sendMessage(requestMessage, os);
+        return receiveMessage(socket.getInputStream());
+    }
+
+    private void ensureSocketIsOpen() throws UnknownHostException, IOException {
+        if (socket == null) {
+            socket = new Socket(host, port);
+        }
+    }
+}

java/com.sap.sailing.domain.swisstimingadapter/src/com/sap/sailing/domain/swisstimingadapter/impl/SailMasterTransceiver.java

@@ -0,0 +1,45 @@
+package com.sap.sailing.domain.swisstimingadapter.impl;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+public class SailMasterTransceiver {
+    private static final byte STX = 0x02;
+    private static final byte ETX = 0x03;
+
+    public void sendMessage(String message, OutputStream os) throws IOException {
+        os.write(STX);
+        os.write(message.getBytes()); // TODO clarify which character set / encoding to use
+        os.write(ETX);
+    }
+
+    public String receiveMessage(InputStream inputStream) throws IOException {
+        // read until an STX byte comes along
+        int read = inputStream.read();
+        while (read != -1 && read != STX) {
+            read = inputStream.read();
+        }
+        String message = null;
+        if (read == STX) {
+            message = readMessage(inputStream);
+        }
+        return message;
+    }
+
+    /**
+     * Read bytes until EOF or ETX is reached and turn those bytes into a string.
+     */
+    private String readMessage(InputStream is) throws IOException {
+        ByteArrayOutputStream bos = new ByteArrayOutputStream(4096);
+        int read = is.read();
+        while (read != -1 && read != ETX) {
+            bos.write(read);
+            read = is.read();
+        }
+        String message = new String(bos.toByteArray()); // TODO clarify character set / encoding with Kai
+        return message;
+    }
+
+}