Bug fix and test to check correct encoding of retain flag

parser/src/main/java/org/dna/mqtt/moquette/proto/Utils.java

@@ -132,10 +132,13 @@ public class Utils {
     }
     
     static byte encodeFlags(AbstractMessage message) {
-         byte flags = 0;
+        byte flags = 0;
         if (message.isDupFlag()) {
             flags |= 0x08;
         }
+        if (message.isRetainFlag()) {
+            flags |= 0x01;
+        }
         
         flags |= ((message.getQos().ordinal() & 0x03) << 1);
         return flags;

parser/src/test/java/org/dna/mqtt/moquette/proto/TestUtils.java

@@ -1,7 +1,5 @@
 package org.dna.mqtt.moquette.proto;
 
-import org.dna.mqtt.moquette.proto.Utils;
-import org.dna.mqtt.moquette.proto.messages.AbstractMessage;
 import java.io.UnsupportedEncodingException;
 import org.apache.mina.core.buffer.IoBuffer;
 import org.apache.mina.core.filterchain.IoFilter.NextFilter;
@@ -9,6 +7,7 @@ import org.apache.mina.core.future.WriteFuture;
 import org.apache.mina.core.session.IoSession;
 import org.apache.mina.filter.codec.ProtocolDecoderOutput;
 import org.apache.mina.filter.codec.ProtocolEncoderOutput;
+import org.dna.mqtt.moquette.proto.messages.AbstractMessage;
 import static org.junit.Assert.*;
 
 /**

parser/src/test/java/org/dna/mqtt/moquette/proto/UtilsTests.java

@@ -0,0 +1,26 @@
+package org.dna.mqtt.moquette.proto;
+
+import org.dna.mqtt.moquette.proto.messages.AbstractMessage;
+import org.dna.mqtt.moquette.proto.messages.UnsubscribeMessage;
+import org.junit.Before;
+import org.junit.Test;
+import static org.junit.Assert.*;
+
+/**
+ *
+ * @author andrea
+ */
+public class UtilsTests {
+    
+    @Test
+    public void testEncodeFlags() {
+        UnsubscribeMessage msg = new UnsubscribeMessage();
+        msg.setRetainFlag(true);
+        msg.setQos(AbstractMessage.QOSType.MOST_ONE);
+        
+        //Exercise
+        assertEquals(1, Utils.encodeFlags(msg));
+    }
+    
+}
+