Improved incoming TopicAliasMapping #175

hivemq · Jul 6, 2018 · 2e49eb2 · 2e49eb2
1 parent e79e082
commit 2e49eb2
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Showing 2 changed files with 12 additions and 8 deletions.
diff --git a/src/main/java/org/mqttbee/mqtt/MqttClientConnectionData.java b/src/main/java/org/mqttbee/mqtt/MqttClientConnectionData.java
@@ -26,6 +26,7 @@
 import org.mqttbee.api.mqtt.mqtt5.auth.Mqtt5EnhancedAuthProvider;
 import org.mqttbee.mqtt.datatypes.MqttTopicImpl;
 import org.mqttbee.mqtt.datatypes.MqttVariableByteInteger;
+import org.mqttbee.util.collections.IntMap;
 
 import java.util.Optional;
 
@@ -37,7 +38,8 @@ public class MqttClientConnectionData implements Mqtt5ClientConnectionData, Mqtt
     private int keepAlive;
     private long sessionExpiryInterval;
     private final int receiveMaximum;
-    private final MqttTopicImpl[] topicAliasMapping;
+    private final int topicAliasMaximum;
+    private final IntMap<MqttTopicImpl> topicAliasMapping;
     private final int maximumPacketSize;
     private final int subscriptionIdentifierMaximum;
     private final Mqtt5EnhancedAuthProvider enhancedAuthProvider;
@@ -56,7 +58,8 @@ public MqttClientConnectionData(
         this.keepAlive = keepAlive;
         this.sessionExpiryInterval = sessionExpiryInterval;
         this.receiveMaximum = receiveMaximum;
-        this.topicAliasMapping = (topicAliasMaximum == 0) ? null : new MqttTopicImpl[topicAliasMaximum];
+        this.topicAliasMaximum = topicAliasMaximum;
+        this.topicAliasMapping = (topicAliasMaximum == 0) ? null : IntMap.range(1, topicAliasMaximum);
         this.maximumPacketSize = maximumPacketSize;
         this.subscriptionIdentifierMaximum =
                 MqttVariableByteInteger.FOUR_BYTES_MAX_VALUE; // TODO CONNECT + CONNACK user properties
@@ -92,11 +95,11 @@ public int getReceiveMaximum() {
 
     @Override
     public int getTopicAliasMaximum() {
-        return (topicAliasMapping == null) ? 0 : topicAliasMapping.length;
+        return topicAliasMaximum;
     }
 
     @Nullable
-    public MqttTopicImpl[] getTopicAliasMapping() {
+    public IntMap<MqttTopicImpl> getTopicAliasMapping() {
         return topicAliasMapping;
     }
 

diff --git a/src/main/java/org/mqttbee/mqtt/codec/decoder/mqtt5/Mqtt5PublishDecoder.java b/src/main/java/org/mqttbee/mqtt/codec/decoder/mqtt5/Mqtt5PublishDecoder.java
@@ -36,6 +36,7 @@
 import org.mqttbee.mqtt.message.publish.MqttStatefulPublish;
 import org.mqttbee.mqtt.netty.ChannelAttributes;
 import org.mqttbee.util.ByteBufferUtil;
+import org.mqttbee.util.collections.IntMap;
 
 import javax.inject.Inject;
 import javax.inject.Singleton;
@@ -183,20 +184,20 @@ public MqttStatefulPublish decode(
 
         boolean isNewTopicAlias = false;
         if (topicAlias != DEFAULT_NO_TOPIC_ALIAS) {
-            final MqttTopicImpl[] topicAliasMapping = clientConnectionData.getTopicAliasMapping();
-            if ((topicAliasMapping == null) || (topicAlias > topicAliasMapping.length)) {
+            final IntMap<MqttTopicImpl> topicAliasMapping = clientConnectionData.getTopicAliasMapping();
+            if ((topicAliasMapping == null) || (topicAlias > clientConnectionData.getTopicAliasMaximum())) {
                 throw new MqttDecoderException(
                         Mqtt5DisconnectReasonCode.TOPIC_ALIAS_INVALID,
                         "topic alias must not exceed topic alias maximum");
             }
             if (topic == null) {
-                topic = topicAliasMapping[topicAlias - 1];
+                topic = topicAliasMapping.get(topicAlias);
                 if (topic == null) {
                     throw new MqttDecoderException(
                             Mqtt5DisconnectReasonCode.TOPIC_ALIAS_INVALID, "topic alias has no mapping");
                 }
             } else {
-                topicAliasMapping[topicAlias - 1] = topic;
+                topicAliasMapping.put(topicAlias, topic);
                 isNewTopicAlias = true;
             }
         } else if (topic == null) {