From 53505a49fd4df319f60b17beb09b5f1bad3a0e09 Mon Sep 17 00:00:00 2001
From: Silvio Giebl <silvio.giebl@hivemq.com>
Date: Fri, 13 Mar 2020 11:17:39 +0100
Subject: [PATCH 1/2] Improved generics on add all methods

---
 .../mqtt/datatypes/MqttUserPropertiesImplBuilder.java       | 4 ++--
 .../mqtt/message/subscribe/MqttSubscribeBuilder.java        | 6 ++++--
 .../message/subscribe/mqtt3/Mqtt3SubscribeViewBuilder.java  | 6 ++++--
 .../mqtt/message/unsubscribe/MqttUnsubscribeBuilder.java    | 4 ++--
 .../unsubscribe/mqtt3/Mqtt3UnsubscribeViewBuilder.java      | 4 ++--
 .../mqtt3/message/subscribe/Mqtt3SubscribeBuilderBase.java  | 4 ++--
 .../message/unsubscribe/Mqtt3UnsubscribeBuilderBase.java    | 4 ++--
 .../mqtt5/datatypes/Mqtt5UserPropertiesBuilderBase.java     | 4 ++--
 .../mqtt5/message/subscribe/Mqtt5SubscribeBuilderBase.java  | 4 ++--
 .../message/unsubscribe/Mqtt5UnsubscribeBuilderBase.java    | 4 ++--
 10 files changed, 24 insertions(+), 20 deletions(-)

diff --git a/src/main/java/com/hivemq/client/internal/mqtt/datatypes/MqttUserPropertiesImplBuilder.java b/src/main/java/com/hivemq/client/internal/mqtt/datatypes/MqttUserPropertiesImplBuilder.java
index d6130b2a8..82a664d15 100644
--- a/src/main/java/com/hivemq/client/internal/mqtt/datatypes/MqttUserPropertiesImplBuilder.java
+++ b/src/main/java/com/hivemq/client/internal/mqtt/datatypes/MqttUserPropertiesImplBuilder.java
@@ -73,14 +73,14 @@ public abstract class MqttUserPropertiesImplBuilder<B extends MqttUserProperties
         return self();
     }
 
-    public @NotNull B addAll(final @Nullable Collection<@Nullable Mqtt5UserProperty> userProperties) {
+    public @NotNull B addAll(final @Nullable Collection<@Nullable ? extends Mqtt5UserProperty> userProperties) {
         Checks.notNull(userProperties, "User Properties");
         listBuilder.ensureFree(userProperties.size());
         userProperties.forEach(this::add);
         return self();
     }
 
-    public @NotNull B addAll(final @Nullable Stream<@Nullable Mqtt5UserProperty> userProperties) {
+    public @NotNull B addAll(final @Nullable Stream<@Nullable ? extends Mqtt5UserProperty> userProperties) {
         Checks.notNull(userProperties, "User Properties");
         userProperties.forEach(this::add);
         return self();
diff --git a/src/main/java/com/hivemq/client/internal/mqtt/message/subscribe/MqttSubscribeBuilder.java b/src/main/java/com/hivemq/client/internal/mqtt/message/subscribe/MqttSubscribeBuilder.java
index 354d06dd4..cce9d6ee9 100644
--- a/src/main/java/com/hivemq/client/internal/mqtt/message/subscribe/MqttSubscribeBuilder.java
+++ b/src/main/java/com/hivemq/client/internal/mqtt/message/subscribe/MqttSubscribeBuilder.java
@@ -78,7 +78,9 @@ protected MqttSubscribeBuilder() {
         return self();
     }
 
-    public @NotNull B addSubscriptions(final @Nullable Collection<@Nullable Mqtt5Subscription> subscriptions) {
+    public @NotNull B addSubscriptions(
+            final @Nullable Collection<@Nullable ? extends Mqtt5Subscription> subscriptions) {
+
         Checks.notNull(subscriptions, "Subscriptions");
         buildFirstSubscription();
         subscriptionsBuilder.ensureFree(subscriptions.size());
@@ -87,7 +89,7 @@ protected MqttSubscribeBuilder() {
         return self();
     }
 
-    public @NotNull B addSubscriptions(final @Nullable Stream<@Nullable Mqtt5Subscription> subscriptions) {
+    public @NotNull B addSubscriptions(final @Nullable Stream<@Nullable ? extends Mqtt5Subscription> subscriptions) {
         Checks.notNull(subscriptions, "Subscriptions");
         buildFirstSubscription();
         subscriptions.forEach(this::addSubscription);
diff --git a/src/main/java/com/hivemq/client/internal/mqtt/message/subscribe/mqtt3/Mqtt3SubscribeViewBuilder.java b/src/main/java/com/hivemq/client/internal/mqtt/message/subscribe/mqtt3/Mqtt3SubscribeViewBuilder.java
index 48d266fd3..88ce3d19d 100644
--- a/src/main/java/com/hivemq/client/internal/mqtt/message/subscribe/mqtt3/Mqtt3SubscribeViewBuilder.java
+++ b/src/main/java/com/hivemq/client/internal/mqtt/message/subscribe/mqtt3/Mqtt3SubscribeViewBuilder.java
@@ -74,7 +74,9 @@ protected Mqtt3SubscribeViewBuilder() {
         return self();
     }
 
-    public @NotNull B addSubscriptions(final @Nullable Collection<@Nullable Mqtt3Subscription> subscriptions) {
+    public @NotNull B addSubscriptions(
+            final @Nullable Collection<@Nullable ? extends Mqtt3Subscription> subscriptions) {
+
         Checks.notNull(subscriptions, "Subscriptions");
         buildFirstSubscription();
         subscriptionsBuilder.ensureFree(subscriptions.size());
@@ -83,7 +85,7 @@ protected Mqtt3SubscribeViewBuilder() {
         return self();
     }
 
-    public @NotNull B addSubscriptions(final @Nullable Stream<@Nullable Mqtt3Subscription> subscriptions) {
+    public @NotNull B addSubscriptions(final @Nullable Stream<@Nullable ? extends Mqtt3Subscription> subscriptions) {
         Checks.notNull(subscriptions, "Subscriptions");
         buildFirstSubscription();
         subscriptions.forEach(this::addSubscription);
diff --git a/src/main/java/com/hivemq/client/internal/mqtt/message/unsubscribe/MqttUnsubscribeBuilder.java b/src/main/java/com/hivemq/client/internal/mqtt/message/unsubscribe/MqttUnsubscribeBuilder.java
index 3c7a444ef..76b598ff2 100644
--- a/src/main/java/com/hivemq/client/internal/mqtt/message/unsubscribe/MqttUnsubscribeBuilder.java
+++ b/src/main/java/com/hivemq/client/internal/mqtt/message/unsubscribe/MqttUnsubscribeBuilder.java
@@ -80,7 +80,7 @@ public abstract class MqttUnsubscribeBuilder<B extends MqttUnsubscribeBuilder<B>
         return self();
     }
 
-    public @NotNull B addTopicFilters(final @Nullable Collection<@Nullable MqttTopicFilter> topicFilters) {
+    public @NotNull B addTopicFilters(final @Nullable Collection<@Nullable ? extends MqttTopicFilter> topicFilters) {
         Checks.notNull(topicFilters, "Topic Filters");
         topicFiltersBuilder.ensureFree(topicFilters.size());
         topicFilters.forEach(this::addTopicFilter);
@@ -88,7 +88,7 @@ public abstract class MqttUnsubscribeBuilder<B extends MqttUnsubscribeBuilder<B>
         return self();
     }
 
-    public @NotNull B addTopicFilters(final @Nullable Stream<@Nullable MqttTopicFilter> topicFilters) {
+    public @NotNull B addTopicFilters(final @Nullable Stream<@Nullable ? extends MqttTopicFilter> topicFilters) {
         Checks.notNull(topicFilters, "Topic Filters");
         topicFilters.forEach(this::addTopicFilter);
         ensureAtLeastOneSubscription();
diff --git a/src/main/java/com/hivemq/client/internal/mqtt/message/unsubscribe/mqtt3/Mqtt3UnsubscribeViewBuilder.java b/src/main/java/com/hivemq/client/internal/mqtt/message/unsubscribe/mqtt3/Mqtt3UnsubscribeViewBuilder.java
index 7c4ca05d2..f131a5ed2 100644
--- a/src/main/java/com/hivemq/client/internal/mqtt/message/unsubscribe/mqtt3/Mqtt3UnsubscribeViewBuilder.java
+++ b/src/main/java/com/hivemq/client/internal/mqtt/message/unsubscribe/mqtt3/Mqtt3UnsubscribeViewBuilder.java
@@ -77,7 +77,7 @@ public abstract class Mqtt3UnsubscribeViewBuilder<B extends Mqtt3UnsubscribeView
         return self();
     }
 
-    public @NotNull B addTopicFilters(final @Nullable Collection<@Nullable MqttTopicFilter> topicFilters) {
+    public @NotNull B addTopicFilters(final @Nullable Collection<@Nullable ? extends MqttTopicFilter> topicFilters) {
         Checks.notNull(topicFilters, "Topic Filters");
         topicFiltersBuilder.ensureFree(topicFilters.size());
         topicFilters.forEach(this::addTopicFilter);
@@ -85,7 +85,7 @@ public abstract class Mqtt3UnsubscribeViewBuilder<B extends Mqtt3UnsubscribeView
         return self();
     }
 
-    public @NotNull B addTopicFilters(final @Nullable Stream<@Nullable MqttTopicFilter> topicFilters) {
+    public @NotNull B addTopicFilters(final @Nullable Stream<@Nullable ? extends MqttTopicFilter> topicFilters) {
         Checks.notNull(topicFilters, "Topic Filters");
         topicFilters.forEach(this::addTopicFilter);
         ensureAtLeastOneSubscription();
diff --git a/src/main/java/com/hivemq/client/mqtt/mqtt3/message/subscribe/Mqtt3SubscribeBuilderBase.java b/src/main/java/com/hivemq/client/mqtt/mqtt3/message/subscribe/Mqtt3SubscribeBuilderBase.java
index 1352f7e83..4161d14e2 100644
--- a/src/main/java/com/hivemq/client/mqtt/mqtt3/message/subscribe/Mqtt3SubscribeBuilderBase.java
+++ b/src/main/java/com/hivemq/client/mqtt/mqtt3/message/subscribe/Mqtt3SubscribeBuilderBase.java
@@ -75,7 +75,7 @@ public interface Mqtt3SubscribeBuilderBase<C extends Mqtt3SubscribeBuilderBase<C
      * @return the builder that is now complete as at least one subscription is set.
      * @since 1.2
      */
-    @NotNull C addSubscriptions(@NotNull Collection<@NotNull Mqtt3Subscription> subscriptions);
+    @NotNull C addSubscriptions(@NotNull Collection<@NotNull ? extends Mqtt3Subscription> subscriptions);
 
     /**
      * Adds a stream of {@link Mqtt3Subscription}s to the {@link Mqtt3Subscribe#getSubscriptions() list of
@@ -85,7 +85,7 @@ public interface Mqtt3SubscribeBuilderBase<C extends Mqtt3SubscribeBuilderBase<C
      * @return the builder that is now complete as at least one subscription is set.
      * @since 1.2
      */
-    @NotNull C addSubscriptions(@NotNull Stream<@NotNull Mqtt3Subscription> subscriptions);
+    @NotNull C addSubscriptions(@NotNull Stream<@NotNull ? extends Mqtt3Subscription> subscriptions);
 
     /**
      * {@link Mqtt3SubscribeBuilderBase} that provides additional methods for the first subscription.
diff --git a/src/main/java/com/hivemq/client/mqtt/mqtt3/message/unsubscribe/Mqtt3UnsubscribeBuilderBase.java b/src/main/java/com/hivemq/client/mqtt/mqtt3/message/unsubscribe/Mqtt3UnsubscribeBuilderBase.java
index 7b5c444e3..e95b7677e 100644
--- a/src/main/java/com/hivemq/client/mqtt/mqtt3/message/unsubscribe/Mqtt3UnsubscribeBuilderBase.java
+++ b/src/main/java/com/hivemq/client/mqtt/mqtt3/message/unsubscribe/Mqtt3UnsubscribeBuilderBase.java
@@ -88,7 +88,7 @@ public interface Mqtt3UnsubscribeBuilderBase<C extends Mqtt3UnsubscribeBuilderBa
      * @return the builder that is now complete as at least one Topic Filter is set.
      * @since 1.2
      */
-    @NotNull C addTopicFilters(@NotNull Collection<@NotNull MqttTopicFilter> topicFilters);
+    @NotNull C addTopicFilters(@NotNull Collection<@NotNull ? extends MqttTopicFilter> topicFilters);
 
     /**
      * Adds a stream of {@link MqttTopicFilter Topic Filters} to the {@link Mqtt3Unsubscribe#getTopicFilters() list of
@@ -98,7 +98,7 @@ public interface Mqtt3UnsubscribeBuilderBase<C extends Mqtt3UnsubscribeBuilderBa
      * @return the builder that is now complete as at least one Topic Filter is set.
      * @since 1.2
      */
-    @NotNull C addTopicFilters(@NotNull Stream<@NotNull MqttTopicFilter> topicFilters);
+    @NotNull C addTopicFilters(@NotNull Stream<@NotNull ? extends MqttTopicFilter> topicFilters);
 
     /**
      * Reverses the subscriptions of a Subscribe message by adding their Topic Filters.
diff --git a/src/main/java/com/hivemq/client/mqtt/mqtt5/datatypes/Mqtt5UserPropertiesBuilderBase.java b/src/main/java/com/hivemq/client/mqtt/mqtt5/datatypes/Mqtt5UserPropertiesBuilderBase.java
index 64c885a2b..3bcae2367 100644
--- a/src/main/java/com/hivemq/client/mqtt/mqtt5/datatypes/Mqtt5UserPropertiesBuilderBase.java
+++ b/src/main/java/com/hivemq/client/mqtt/mqtt5/datatypes/Mqtt5UserPropertiesBuilderBase.java
@@ -80,7 +80,7 @@ public interface Mqtt5UserPropertiesBuilderBase<B extends Mqtt5UserPropertiesBui
      * @return the builder.
      * @since 1.2
      */
-    @NotNull B addAll(@NotNull Collection<@NotNull Mqtt5UserProperty> userProperties);
+    @NotNull B addAll(@NotNull Collection<@NotNull ? extends Mqtt5UserProperty> userProperties);
 
     /**
      * Adds a stream of {@link Mqtt5UserProperty User Properties}.
@@ -89,5 +89,5 @@ public interface Mqtt5UserPropertiesBuilderBase<B extends Mqtt5UserPropertiesBui
      * @return the builder.
      * @since 1.2
      */
-    @NotNull B addAll(@NotNull Stream<@NotNull Mqtt5UserProperty> userProperties);
+    @NotNull B addAll(@NotNull Stream<@NotNull ? extends Mqtt5UserProperty> userProperties);
 }
diff --git a/src/main/java/com/hivemq/client/mqtt/mqtt5/message/subscribe/Mqtt5SubscribeBuilderBase.java b/src/main/java/com/hivemq/client/mqtt/mqtt5/message/subscribe/Mqtt5SubscribeBuilderBase.java
index 143a402dc..07d9c0b50 100644
--- a/src/main/java/com/hivemq/client/mqtt/mqtt5/message/subscribe/Mqtt5SubscribeBuilderBase.java
+++ b/src/main/java/com/hivemq/client/mqtt/mqtt5/message/subscribe/Mqtt5SubscribeBuilderBase.java
@@ -77,7 +77,7 @@ public interface Mqtt5SubscribeBuilderBase<C extends Mqtt5SubscribeBuilderBase.C
      * @return the builder that is now complete as at least one subscription is set.
      * @since 1.2
      */
-    @NotNull C addSubscriptions(@NotNull Collection<@NotNull Mqtt5Subscription> subscriptions);
+    @NotNull C addSubscriptions(@NotNull Collection<@NotNull ? extends Mqtt5Subscription> subscriptions);
 
     /**
      * Adds a stream of {@link Mqtt5Subscription}s to the {@link Mqtt5Subscribe#getSubscriptions() list of
@@ -87,7 +87,7 @@ public interface Mqtt5SubscribeBuilderBase<C extends Mqtt5SubscribeBuilderBase.C
      * @return the builder that is now complete as at least one subscription is set.
      * @since 1.2
      */
-    @NotNull C addSubscriptions(@NotNull Stream<@NotNull Mqtt5Subscription> subscriptions);
+    @NotNull C addSubscriptions(@NotNull Stream<@NotNull ? extends Mqtt5Subscription> subscriptions);
 
     /**
      * {@link Mqtt5SubscribeBuilderBase} that is complete which means all mandatory fields are set.
diff --git a/src/main/java/com/hivemq/client/mqtt/mqtt5/message/unsubscribe/Mqtt5UnsubscribeBuilderBase.java b/src/main/java/com/hivemq/client/mqtt/mqtt5/message/unsubscribe/Mqtt5UnsubscribeBuilderBase.java
index b844cf468..55fa10291 100644
--- a/src/main/java/com/hivemq/client/mqtt/mqtt5/message/unsubscribe/Mqtt5UnsubscribeBuilderBase.java
+++ b/src/main/java/com/hivemq/client/mqtt/mqtt5/message/unsubscribe/Mqtt5UnsubscribeBuilderBase.java
@@ -90,7 +90,7 @@ public interface Mqtt5UnsubscribeBuilderBase<C extends Mqtt5UnsubscribeBuilderBa
      * @return the builder that is now complete as at least one Topic Filter is set.
      * @since 1.2
      */
-    @NotNull C addTopicFilters(@NotNull Collection<@NotNull MqttTopicFilter> topicFilters);
+    @NotNull C addTopicFilters(@NotNull Collection<@NotNull ? extends MqttTopicFilter> topicFilters);
 
     /**
      * Adds a stream of {@link MqttTopicFilter Topic Filters} to the {@link Mqtt5Unsubscribe#getTopicFilters() list of
@@ -100,7 +100,7 @@ public interface Mqtt5UnsubscribeBuilderBase<C extends Mqtt5UnsubscribeBuilderBa
      * @return the builder that is now complete as at least one Topic Filter is set.
      * @since 1.2
      */
-    @NotNull C addTopicFilters(@NotNull Stream<@NotNull MqttTopicFilter> topicFilters);
+    @NotNull C addTopicFilters(@NotNull Stream<@NotNull ? extends MqttTopicFilter> topicFilters);
 
     /**
      * Reverses the subscriptions of a Subscribe message by adding their Topic Filters.

From 6f690dea74517a6b320206b7939d02de53fe3bc2 Mon Sep 17 00:00:00 2001
From: Silvio Giebl <silvio.giebl@hivemq.com>
Date: Fri, 13 Mar 2020 11:18:36 +0100
Subject: [PATCH 2/2] Added missing CheckReturnValue annotations

---
 .../com/hivemq/client/mqtt/MqttWebSocketConfigBuilderBase.java | 1 +
 .../mqtt3/message/subscribe/Mqtt3SubscribeBuilderBase.java     | 3 +++
 .../mqtt3/message/unsubscribe/Mqtt3UnsubscribeBuilderBase.java | 3 +++
 .../mqtt/mqtt5/datatypes/Mqtt5UserPropertiesBuilderBase.java   | 3 +++
 .../mqtt5/message/subscribe/Mqtt5SubscribeBuilderBase.java     | 3 +++
 .../mqtt5/message/unsubscribe/Mqtt5UnsubscribeBuilderBase.java | 3 +++
 6 files changed, 16 insertions(+)

diff --git a/src/main/java/com/hivemq/client/mqtt/MqttWebSocketConfigBuilderBase.java b/src/main/java/com/hivemq/client/mqtt/MqttWebSocketConfigBuilderBase.java
index b42c93962..f21146c4f 100644
--- a/src/main/java/com/hivemq/client/mqtt/MqttWebSocketConfigBuilderBase.java
+++ b/src/main/java/com/hivemq/client/mqtt/MqttWebSocketConfigBuilderBase.java
@@ -46,6 +46,7 @@ public interface MqttWebSocketConfigBuilderBase<B extends MqttWebSocketConfigBui
      * @param queryString the query string.
      * @return the builder.
      */
+    @CheckReturnValue
     @NotNull B queryString(@NotNull String queryString);
 
     /**
diff --git a/src/main/java/com/hivemq/client/mqtt/mqtt3/message/subscribe/Mqtt3SubscribeBuilderBase.java b/src/main/java/com/hivemq/client/mqtt/mqtt3/message/subscribe/Mqtt3SubscribeBuilderBase.java
index 4161d14e2..a3d12a1d3 100644
--- a/src/main/java/com/hivemq/client/mqtt/mqtt3/message/subscribe/Mqtt3SubscribeBuilderBase.java
+++ b/src/main/java/com/hivemq/client/mqtt/mqtt3/message/subscribe/Mqtt3SubscribeBuilderBase.java
@@ -65,6 +65,7 @@ public interface Mqtt3SubscribeBuilderBase<C extends Mqtt3SubscribeBuilderBase<C
      * @return the builder that is now complete as at least one subscription is set.
      * @since 1.2
      */
+    @CheckReturnValue
     @NotNull C addSubscriptions(@NotNull Mqtt3Subscription @NotNull ... subscriptions);
 
     /**
@@ -75,6 +76,7 @@ public interface Mqtt3SubscribeBuilderBase<C extends Mqtt3SubscribeBuilderBase<C
      * @return the builder that is now complete as at least one subscription is set.
      * @since 1.2
      */
+    @CheckReturnValue
     @NotNull C addSubscriptions(@NotNull Collection<@NotNull ? extends Mqtt3Subscription> subscriptions);
 
     /**
@@ -85,6 +87,7 @@ public interface Mqtt3SubscribeBuilderBase<C extends Mqtt3SubscribeBuilderBase<C
      * @return the builder that is now complete as at least one subscription is set.
      * @since 1.2
      */
+    @CheckReturnValue
     @NotNull C addSubscriptions(@NotNull Stream<@NotNull ? extends Mqtt3Subscription> subscriptions);
 
     /**
diff --git a/src/main/java/com/hivemq/client/mqtt/mqtt3/message/unsubscribe/Mqtt3UnsubscribeBuilderBase.java b/src/main/java/com/hivemq/client/mqtt/mqtt3/message/unsubscribe/Mqtt3UnsubscribeBuilderBase.java
index e95b7677e..2dfa8abdf 100644
--- a/src/main/java/com/hivemq/client/mqtt/mqtt3/message/unsubscribe/Mqtt3UnsubscribeBuilderBase.java
+++ b/src/main/java/com/hivemq/client/mqtt/mqtt3/message/unsubscribe/Mqtt3UnsubscribeBuilderBase.java
@@ -78,6 +78,7 @@ public interface Mqtt3UnsubscribeBuilderBase<C extends Mqtt3UnsubscribeBuilderBa
      * @return the builder that is now complete as at least one Topic Filter is set.
      * @since 1.2
      */
+    @CheckReturnValue
     @NotNull C addTopicFilters(@NotNull MqttTopicFilter @NotNull ... topicFilters);
 
     /**
@@ -88,6 +89,7 @@ public interface Mqtt3UnsubscribeBuilderBase<C extends Mqtt3UnsubscribeBuilderBa
      * @return the builder that is now complete as at least one Topic Filter is set.
      * @since 1.2
      */
+    @CheckReturnValue
     @NotNull C addTopicFilters(@NotNull Collection<@NotNull ? extends MqttTopicFilter> topicFilters);
 
     /**
@@ -98,6 +100,7 @@ public interface Mqtt3UnsubscribeBuilderBase<C extends Mqtt3UnsubscribeBuilderBa
      * @return the builder that is now complete as at least one Topic Filter is set.
      * @since 1.2
      */
+    @CheckReturnValue
     @NotNull C addTopicFilters(@NotNull Stream<@NotNull ? extends MqttTopicFilter> topicFilters);
 
     /**
diff --git a/src/main/java/com/hivemq/client/mqtt/mqtt5/datatypes/Mqtt5UserPropertiesBuilderBase.java b/src/main/java/com/hivemq/client/mqtt/mqtt5/datatypes/Mqtt5UserPropertiesBuilderBase.java
index 3bcae2367..512f3443f 100644
--- a/src/main/java/com/hivemq/client/mqtt/mqtt5/datatypes/Mqtt5UserPropertiesBuilderBase.java
+++ b/src/main/java/com/hivemq/client/mqtt/mqtt5/datatypes/Mqtt5UserPropertiesBuilderBase.java
@@ -71,6 +71,7 @@ public interface Mqtt5UserPropertiesBuilderBase<B extends Mqtt5UserPropertiesBui
      * @return the builder.
      * @since 1.2
      */
+    @CheckReturnValue
     @NotNull B addAll(@NotNull Mqtt5UserProperty @NotNull ... userProperties);
 
     /**
@@ -80,6 +81,7 @@ public interface Mqtt5UserPropertiesBuilderBase<B extends Mqtt5UserPropertiesBui
      * @return the builder.
      * @since 1.2
      */
+    @CheckReturnValue
     @NotNull B addAll(@NotNull Collection<@NotNull ? extends Mqtt5UserProperty> userProperties);
 
     /**
@@ -89,5 +91,6 @@ public interface Mqtt5UserPropertiesBuilderBase<B extends Mqtt5UserPropertiesBui
      * @return the builder.
      * @since 1.2
      */
+    @CheckReturnValue
     @NotNull B addAll(@NotNull Stream<@NotNull ? extends Mqtt5UserProperty> userProperties);
 }
diff --git a/src/main/java/com/hivemq/client/mqtt/mqtt5/message/subscribe/Mqtt5SubscribeBuilderBase.java b/src/main/java/com/hivemq/client/mqtt/mqtt5/message/subscribe/Mqtt5SubscribeBuilderBase.java
index 07d9c0b50..1a8b98f08 100644
--- a/src/main/java/com/hivemq/client/mqtt/mqtt5/message/subscribe/Mqtt5SubscribeBuilderBase.java
+++ b/src/main/java/com/hivemq/client/mqtt/mqtt5/message/subscribe/Mqtt5SubscribeBuilderBase.java
@@ -67,6 +67,7 @@ public interface Mqtt5SubscribeBuilderBase<C extends Mqtt5SubscribeBuilderBase.C
      * @return the builder that is now complete as at least one subscription is set.
      * @since 1.2
      */
+    @CheckReturnValue
     @NotNull C addSubscriptions(@NotNull Mqtt5Subscription @NotNull ... subscriptions);
 
     /**
@@ -77,6 +78,7 @@ public interface Mqtt5SubscribeBuilderBase<C extends Mqtt5SubscribeBuilderBase.C
      * @return the builder that is now complete as at least one subscription is set.
      * @since 1.2
      */
+    @CheckReturnValue
     @NotNull C addSubscriptions(@NotNull Collection<@NotNull ? extends Mqtt5Subscription> subscriptions);
 
     /**
@@ -87,6 +89,7 @@ public interface Mqtt5SubscribeBuilderBase<C extends Mqtt5SubscribeBuilderBase.C
      * @return the builder that is now complete as at least one subscription is set.
      * @since 1.2
      */
+    @CheckReturnValue
     @NotNull C addSubscriptions(@NotNull Stream<@NotNull ? extends Mqtt5Subscription> subscriptions);
 
     /**
diff --git a/src/main/java/com/hivemq/client/mqtt/mqtt5/message/unsubscribe/Mqtt5UnsubscribeBuilderBase.java b/src/main/java/com/hivemq/client/mqtt/mqtt5/message/unsubscribe/Mqtt5UnsubscribeBuilderBase.java
index 55fa10291..a25e760f4 100644
--- a/src/main/java/com/hivemq/client/mqtt/mqtt5/message/unsubscribe/Mqtt5UnsubscribeBuilderBase.java
+++ b/src/main/java/com/hivemq/client/mqtt/mqtt5/message/unsubscribe/Mqtt5UnsubscribeBuilderBase.java
@@ -80,6 +80,7 @@ public interface Mqtt5UnsubscribeBuilderBase<C extends Mqtt5UnsubscribeBuilderBa
      * @return the builder that is now complete as at least one Topic Filter is set.
      * @since 1.2
      */
+    @CheckReturnValue
     @NotNull C addTopicFilters(@NotNull MqttTopicFilter @NotNull ... topicFilters);
 
     /**
@@ -90,6 +91,7 @@ public interface Mqtt5UnsubscribeBuilderBase<C extends Mqtt5UnsubscribeBuilderBa
      * @return the builder that is now complete as at least one Topic Filter is set.
      * @since 1.2
      */
+    @CheckReturnValue
     @NotNull C addTopicFilters(@NotNull Collection<@NotNull ? extends MqttTopicFilter> topicFilters);
 
     /**
@@ -100,6 +102,7 @@ public interface Mqtt5UnsubscribeBuilderBase<C extends Mqtt5UnsubscribeBuilderBa
      * @return the builder that is now complete as at least one Topic Filter is set.
      * @since 1.2
      */
+    @CheckReturnValue
     @NotNull C addTopicFilters(@NotNull Stream<@NotNull ? extends MqttTopicFilter> topicFilters);
 
     /**