1 files changed, 62 insertions, 0 deletions
diff --git a/sources/protocols/ExternalTimeSyncProtocol.java b/sources/protocols/ExternalTimeSyncProtocol.java
new file mode 100644
index 0000000..33a60ad
--- /dev/null
+++ b/sources/protocols/ExternalTimeSyncProtocol.java
@@ -0,0 +1,62 @@
+package protocols;
+
+import prefs.VSPrefs;
+import core.VSMessage;
+
+public class ExternalTimeSyncProtocol extends VSProtocol {
+    private long requestTime;
+    private boolean waitingForResponse;
+
+    public ExternalTimeSyncProtocol() {
+        setProtocolClassname(getClass().toString());
+    }
+
+    protected void onClientReset() {
+    }
+
+    protected void onClientStart() {
+        requestTime = process.getTime();
+        waitingForResponse = true;
+
+        /* Multicast message to all processes */
+        VSMessage message = new VSMessage(getProtocolClassname());
+        message.setBoolean("isClientRequest", true);
+        sendMessage(message);
+    }
+
+    protected void onClientRecv(VSMessage recvMessage) {
+        if (!recvMessage.getBoolean("isServerResponse"))
+            return;
+
+        if (waitingForResponse)
+            waitingForResponse = false;
+        else
+            return;
+
+        long recvTime = process.getTime();
+        long roundTripTime = recvTime - requestTime;
+        long serverTime = recvMessage.getLong("time");
+        long newTime = serverTime + (long) (roundTripTime / 2);
+
+        logg("Server Zeit: " + serverTime + "; RTT: " + roundTripTime + "; Alte Zeit: " + recvTime + "; Neue Zeit: " + newTime + "; Offset: " + (newTime - recvTime));
+        process.setTime(newTime);
+    }
+
+    protected void onServerReset() {
+    }
+
+    protected void onServerRecv(VSMessage recvMessage) {
+        if (!recvMessage.getBoolean("isClientRequest"))
+            return;
+
+        /* Multicast message to all processes */
+        VSMessage message = new VSMessage(getProtocolClassname());
+        message.setLong("time", process.getTime());
+        message.setBoolean("isServerResponse", true);
+        sendMessage(message);
+    }
+
+    public String toString() {
+        return super.toString(); //+ "; " + prefs.getString("lang.requesttime") + ": " + requestTime;
+    }
+}