diff --git a/rcljava/src/main/java/org/ros2/rcljava/action/ActionServerImpl.java b/rcljava/src/main/java/org/ros2/rcljava/action/ActionServerImpl.java
index ed379c6b..bd6e5f2d 100644
--- a/rcljava/src/main/java/org/ros2/rcljava/action/ActionServerImpl.java
+++ b/rcljava/src/main/java/org/ros2/rcljava/action/ActionServerImpl.java
@@ -16,6 +16,7 @@
 package org.ros2.rcljava.action;
 
 import java.lang.ref.WeakReference;
+import java.lang.SuppressWarnings;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
@@ -171,6 +172,8 @@ public synchronized void abort(ResultDefinition<T> result) {
     /**
      * {@inheritDoc}
      */
+    // TODO(ivanpauno): Improve generated code API so we don't need this.
+    @SuppressWarnings("unchecked")
     public synchronized void publishFeedback(FeedbackDefinition<T> feedback) {
       Class<? extends FeedbackMessageDefinition> feedbackMessageType =
         ActionServerImpl.this.actionTypeInstance.getFeedbackMessageType();
@@ -202,7 +205,7 @@ public final long getHandle() {
 
     private synchronized final void toTerminalState(byte status, ResultDefinition<T> result) {
       nativeUpdateGoalState(this.handle, status);
-      ResultResponseDefinition<T> resultResponse = ActionServerImpl.this.createResultResponse();
+      ResultResponseDefinition<T> resultResponse = ActionServerImpl.this.createResultResponseUnchecked();
       resultResponse.setGoalStatus(status);
       resultResponse.setResult(result);
       ActionServerImpl.this.sendResult(goalInfo.getGoalId().getUuidAsList(), resultResponse);
@@ -337,6 +340,12 @@ public boolean isReady(long waitSetHandle) {
     return false;
   }
 
+  @SuppressWarnings("unchecked")
+  private GoalCallback.GoalResponse
+  handleGoalUnchecked(GoalRequestDefinition<T> requestMessage) {
+    return this.goalCallback.handleGoal(requestMessage);
+  }
+
   private ActionServerGoalHandle<T> executeGoalRequest(
     RMWRequestId rmwRequestId,
     GoalRequestDefinition<T> requestMessage,
@@ -358,7 +367,7 @@ private ActionServerGoalHandle<T> executeGoalRequest(
     }
 
     // Call user callback
-    GoalCallback.GoalResponse response = this.goalCallback.handleGoal(requestMessage);
+    GoalCallback.GoalResponse response = this.handleGoalUnchecked(requestMessage);
 
     boolean accepted = GoalCallback.GoalResponse.ACCEPT_AND_DEFER == response
       || GoalCallback.GoalResponse.ACCEPT_AND_EXECUTE == response;
@@ -542,17 +551,6 @@ private action_msgs.msg.GoalInfo createGoalInfo(List<Byte> goalUuid) {
     return goalInfo;
   }
 
-  private ResultResponseDefinition<T> createResultResponse() {
-    ResultResponseDefinition<T> resultResponse;
-    try {
-      resultResponse =
-        this.actionTypeInstance.getGetResultResponseType().getDeclaredConstructor().newInstance();
-    } catch (ReflectiveOperationException ex) {
-      throw new IllegalStateException("Failed to instantiate provided action type: ", ex);
-    }
-    return resultResponse;
-  }
-
   // This will store the result, so it can be sent to future result requests, and 
   // will also send a result response to all requests that were already made.
   private void sendResult(List<Byte> goalUuid, ResultResponseDefinition<T> resultResponse) {
@@ -571,23 +569,61 @@ private void sendResult(List<Byte> goalUuid, ResultResponseDefinition<T> resultR
     }
   }
 
+  // TODO(ivanpauno): Improve generated code API so we don't need this.
+  @SuppressWarnings("unchecked")
+  private ResultRequestDefinition<T> createResultRequestUnchecked() {
+    ResultRequestDefinition<T> resultRequest;
+    try {
+      resultRequest =
+        this.actionTypeInstance.getGetResultRequestType().getDeclaredConstructor().newInstance();
+    } catch (ReflectiveOperationException ex) {
+      throw new IllegalStateException("Failed to instantiate provided action type: ", ex);
+    }
+    return resultRequest;
+  }
+
+  // TODO(ivanpauno): Improve generated code API so we don't need this.
+  @SuppressWarnings("unchecked")
+  private ResultResponseDefinition<T> createResultResponseUnchecked() {
+    ResultResponseDefinition<T> resultResponse;
+    try {
+      resultResponse =
+        this.actionTypeInstance.getGetResultResponseType().getDeclaredConstructor().newInstance();
+    } catch (ReflectiveOperationException ex) {
+      throw new IllegalStateException("Failed to instantiate provided action type: ", ex);
+    }
+    return resultResponse;
+  }
+
+  // TODO(ivanpauno): Improve generated code API so we don't need this.
+  @SuppressWarnings("unchecked")
+  private GoalRequestDefinition<T> newRequestUnchecked() {
+    Class<? extends GoalRequestDefinition> requestType = this.actionTypeInstance.getSendGoalRequestType();
+    try {
+      return requestType.getDeclaredConstructor().newInstance();
+    } catch (ReflectiveOperationException ex) {
+      throw new IllegalStateException("Failed to instantiate request: ", ex);
+    }
+  }
+
+  // TODO(ivanpauno): Improve generated code API so we don't need this.
+  @SuppressWarnings("unchecked")
+  private GoalResponseDefinition<T> newResponseUnchecked() {
+    Class<? extends GoalResponseDefinition> responseType = this.actionTypeInstance.getSendGoalResponseType();
+    try {
+      return responseType.getDeclaredConstructor().newInstance();
+    } catch (ReflectiveOperationException ex) {
+      throw new IllegalStateException("Failed to instantiate responce: ", ex);
+    }
+  }
+
   /**
    * {@inheritDoc}
    */
   public void execute() {
     if (this.isGoalRequestReady()) {
-      Class<? extends GoalRequestDefinition> requestType = this.actionTypeInstance.getSendGoalRequestType();
-      Class<? extends GoalResponseDefinition> responseType = this.actionTypeInstance.getSendGoalResponseType();
-
-      GoalRequestDefinition<T> requestMessage = null;
-      GoalResponseDefinition<T> responseMessage = null;
-
-      try {
-        requestMessage = requestType.getDeclaredConstructor().newInstance();
-        responseMessage = responseType.getDeclaredConstructor().newInstance();
-      } catch (ReflectiveOperationException ex) {
-        throw new IllegalStateException("Failed to instantiate request or responce: ", ex);
-      }
+      GoalRequestDefinition<T> requestMessage = newRequestUnchecked();
+      GoalResponseDefinition<T> responseMessage = newResponseUnchecked();
 
       if (requestMessage != null && responseMessage != null) {
         long requestFromJavaConverterHandle = requestMessage.getFromJavaConverterInstance();
@@ -643,14 +679,7 @@ public void execute() {
     }
 
     if (this.isResultRequestReady()) {
-      Class<? extends ResultRequestDefinition> requestType = this.actionTypeInstance.getGetResultRequestType();
-
-      ResultRequestDefinition<T> requestMessage = null;
-      try {
-        requestMessage = requestType.getDeclaredConstructor().newInstance();
-      } catch (ReflectiveOperationException ex) {
-        throw new IllegalArgumentException("Failed to instantiate action result request: ", ex);
-      }
+      ResultRequestDefinition<T> requestMessage = createResultRequestUnchecked();
 
       if (requestMessage != null) {
         long requestFromJavaConverterHandle = requestMessage.getFromJavaConverterInstance();
@@ -672,7 +701,7 @@ public void execute() {
 
         ResultResponseDefinition<T> resultResponse = null;
         if (!goalExists) {
-          resultResponse = this.createResultResponse();
+          resultResponse = this.createResultResponseUnchecked();
           resultResponse.setGoalStatus(action_msgs.msg.GoalStatus.STATUS_UNKNOWN);
         } else {
           resultResponse = this.goalResults.get(goalUuid);
@@ -682,7 +711,7 @@ public void execute() {
           List<RMWRequestId> requestIds = null;
           requestIds = this.goalRequests.get(goalUuid);
           if (requestIds == null) {
-            requestIds = new ArrayList();
+            requestIds = new ArrayList<RMWRequestId>();
             this.goalRequests.put(goalUuid, requestIds);
           }
           requestIds.add(rmwRequestId);
diff --git a/rcljava/src/main/java/org/ros2/rcljava/node/NodeImpl.java b/rcljava/src/main/java/org/ros2/rcljava/node/NodeImpl.java
index 3ca6cfb6..0ac0ee9f 100644
--- a/rcljava/src/main/java/org/ros2/rcljava/node/NodeImpl.java
+++ b/rcljava/src/main/java/org/ros2/rcljava/node/NodeImpl.java
@@ -879,7 +879,7 @@ public rcl_interfaces.msg.ListParametersResult listParameters(
   }
 
   public final Collection<NodeNameInfo> getNodeNames() {
-    ArrayList<NodeNameInfo> nodeNames = new ArrayList();
+    ArrayList<NodeNameInfo> nodeNames = new ArrayList<NodeNameInfo>();
     nativeGetNodeNames(this.handle, nodeNames);
     return nodeNames;
   }
@@ -887,7 +887,7 @@ public final Collection<NodeNameInfo> getNodeNames() {
   private native static final void nativeGetNodeNames(long handle, ArrayList<NodeNameInfo> nodeNames);
 
   public final Collection<NameAndTypes> getTopicNamesAndTypes() {
-    Collection<NameAndTypes> namesAndTypes = new ArrayList();
+    Collection<NameAndTypes> namesAndTypes = new ArrayList<NameAndTypes>();
     nativeGetTopicNamesAndTypes(this.handle, namesAndTypes);
     return namesAndTypes;
   }
@@ -896,7 +896,7 @@ private static native final void nativeGetTopicNamesAndTypes(
     long handle, Collection<NameAndTypes> namesAndTypes);
 
   public final Collection<NameAndTypes> getServiceNamesAndTypes() {
-    Collection<NameAndTypes> namesAndTypes = new ArrayList();
+    Collection<NameAndTypes> namesAndTypes = new ArrayList<NameAndTypes>();
     nativeGetServiceNamesAndTypes(this.handle, namesAndTypes);
     return namesAndTypes;
   }
@@ -905,7 +905,7 @@ private static native final void nativeGetServiceNamesAndTypes(
     long handle, Collection<NameAndTypes> namesAndTypes);
 
   public final Collection<EndpointInfo> getPublishersInfo(final String topicName) {
-    ArrayList<EndpointInfo> returnValue = new ArrayList();
+    ArrayList<EndpointInfo> returnValue = new ArrayList<EndpointInfo>();
     nativeGetPublishersInfo(this.handle, topicName, returnValue);
     return returnValue;
   }
@@ -914,7 +914,7 @@ private native static final void nativeGetPublishersInfo(
     final long handle, final String topicName, ArrayList<EndpointInfo> endpointInfo);
 
   public final Collection<EndpointInfo> getSubscriptionsInfo(final String topicName) {
-    ArrayList<EndpointInfo> returnValue = new ArrayList();
+    ArrayList<EndpointInfo> returnValue = new ArrayList<EndpointInfo>();
     nativeGetSubscriptionsInfo(this.handle, topicName, returnValue);
     return returnValue;
   }
@@ -925,7 +925,7 @@ private native static final void nativeGetSubscriptionsInfo(
   public final Collection<NameAndTypes> getPublisherNamesAndTypesByNode(
     String nodeName, String nodeNamespace)
   {
-    Collection<NameAndTypes> namesAndTypes = new ArrayList();
+    Collection<NameAndTypes> namesAndTypes = new ArrayList<NameAndTypes>();
     nativeGetPublisherNamesAndTypesByNode(this.handle, nodeName, nodeNamespace, namesAndTypes);
     return namesAndTypes;
   }
@@ -936,7 +936,7 @@ private static native final Collection<NameAndTypes> nativeGetPublisherNamesAndT
   public final Collection<NameAndTypes> getSubscriptionNamesAndTypesByNode(
     String nodeName, String nodeNamespace)
   {
-    Collection<NameAndTypes> namesAndTypes = new ArrayList();
+    Collection<NameAndTypes> namesAndTypes = new ArrayList<NameAndTypes>();
     nativeGetSubscriptionNamesAndTypesByNode(this.handle, nodeName, nodeNamespace, namesAndTypes);
     return namesAndTypes;
   }
@@ -947,7 +947,7 @@ private static native final Collection<NameAndTypes> nativeGetSubscriptionNamesA
   public final Collection<NameAndTypes> getServiceNamesAndTypesByNode(
     String nodeName, String nodeNamespace)
   {
-    Collection<NameAndTypes> namesAndTypes = new ArrayList();
+    Collection<NameAndTypes> namesAndTypes = new ArrayList<NameAndTypes>();
     nativeGetServiceNamesAndTypesByNode(this.handle, nodeName, nodeNamespace, namesAndTypes);
     return namesAndTypes;
   }
@@ -958,7 +958,7 @@ private static native final Collection<NameAndTypes> nativeGetServiceNamesAndTyp
   public final Collection<NameAndTypes> getClientNamesAndTypesByNode(
     String nodeName, String nodeNamespace)
   {
-    Collection<NameAndTypes> namesAndTypes = new ArrayList();
+    Collection<NameAndTypes> namesAndTypes = new ArrayList<NameAndTypes>();
     nativeGetClientNamesAndTypesByNode(this.handle, nodeName, nodeNamespace, namesAndTypes);
     return namesAndTypes;
   }
diff --git a/rcljava/src/main/java/org/ros2/rcljava/publisher/PublisherImpl.java b/rcljava/src/main/java/org/ros2/rcljava/publisher/PublisherImpl.java
index 7911916b..1bd493fa 100644
--- a/rcljava/src/main/java/org/ros2/rcljava/publisher/PublisherImpl.java
+++ b/rcljava/src/main/java/org/ros2/rcljava/publisher/PublisherImpl.java
@@ -117,8 +117,8 @@ public final WeakReference<Node> getNodeReference() {
   public final
   <T extends PublisherEventStatus> EventHandler<T, Publisher>
   createEventHandler(Supplier<T> factory, Consumer<T> callback) {
-    final WeakReference<Collection<EventHandler>> weakEventHandlers = new WeakReference(
-      this.eventHandlers);
+    final WeakReference<Collection<EventHandler>> weakEventHandlers =
+      new WeakReference<Collection<EventHandler>>(this.eventHandlers);
     Consumer<EventHandler> disposeCallback = new Consumer<EventHandler>() {
       public void accept(EventHandler eventHandler) {
         Collection<EventHandler> eventHandlers = weakEventHandlers.get();
@@ -129,7 +129,7 @@ public void accept(EventHandler eventHandler) {
     };
     T status = factory.get();
     long eventHandle = nativeCreateEvent(this.handle, status.getPublisherEventType());
-    EventHandler<T, Publisher> eventHandler = new EventHandlerImpl(
+    EventHandler<T, Publisher> eventHandler = new EventHandlerImpl<T, Publisher>(
       new WeakReference<Publisher>(this), eventHandle, factory, callback, disposeCallback);
     this.eventHandlers.add(eventHandler);
     return eventHandler;
diff --git a/rcljava/src/main/java/org/ros2/rcljava/subscription/SubscriptionImpl.java b/rcljava/src/main/java/org/ros2/rcljava/subscription/SubscriptionImpl.java
index 7a969af0..34c3e3cf 100644
--- a/rcljava/src/main/java/org/ros2/rcljava/subscription/SubscriptionImpl.java
+++ b/rcljava/src/main/java/org/ros2/rcljava/subscription/SubscriptionImpl.java
@@ -129,8 +129,8 @@ public final WeakReference<Node> getNodeReference() {
   public final
   <T extends SubscriptionEventStatus> EventHandler<T, Subscription>
   createEventHandler(Supplier<T> factory, Consumer<T> callback) {
-    final WeakReference<Collection<EventHandler>> weakEventHandlers = new WeakReference(
-      this.eventHandlers);
+    final WeakReference<Collection<EventHandler>> weakEventHandlers =
+      new WeakReference<Collection<EventHandler>>(this.eventHandlers);
     Consumer<EventHandler> disposeCallback = new Consumer<EventHandler>() {
       public void accept(EventHandler eventHandler) {
         Collection<EventHandler> eventHandlers = weakEventHandlers.get();
@@ -141,8 +141,9 @@ public void accept(EventHandler eventHandler) {
     };
     T status = factory.get();
     long eventHandle = nativeCreateEvent(this.handle, status.getSubscriptionEventType());
-    EventHandler<T, Subscription> eventHandler = new EventHandlerImpl(
-      new WeakReference<Subscription>(this), eventHandle, factory, callback, disposeCallback);
+    EventHandler<T, Subscription> eventHandler =
+      new EventHandlerImpl<T, Subscription>(
+        new WeakReference<Subscription>(this), eventHandle, factory, callback, disposeCallback);
     this.eventHandlers.add(eventHandler);
     return eventHandler;
   }
diff --git a/rcljava/src/test/java/org/ros2/rcljava/client/ClientTest.java b/rcljava/src/test/java/org/ros2/rcljava/client/ClientTest.java
index d7a15bbd..867d4eaf 100644
--- a/rcljava/src/test/java/org/ros2/rcljava/client/ClientTest.java
+++ b/rcljava/src/test/java/org/ros2/rcljava/client/ClientTest.java
@@ -54,7 +54,7 @@ public static void setupOnce() throws Exception {
     {
       // Configure log4j. Doing this dynamically so that Android does not complain about missing
       // the log4j JARs, SLF4J uses Android's native logging mechanism instead.
-      Class c = Class.forName("org.apache.log4j.BasicConfigurator");
+      Class<?> c = Class.forName("org.apache.log4j.BasicConfigurator");
       Method m = c.getDeclaredMethod("configure", (Class<?>[]) null);
       Object o = m.invoke(null, (Object[]) null);
     }
diff --git a/rcljava/src/test/java/org/ros2/rcljava/node/NodeTest.java b/rcljava/src/test/java/org/ros2/rcljava/node/NodeTest.java
index 29597325..cb668421 100644
--- a/rcljava/src/test/java/org/ros2/rcljava/node/NodeTest.java
+++ b/rcljava/src/test/java/org/ros2/rcljava/node/NodeTest.java
@@ -112,7 +112,7 @@ public static void setupOnce() throws Exception {
     {
       // Configure log4j. Doing this dynamically so that Android does not complain about missing
       // the log4j JARs, SLF4J uses Android's native logging mechanism instead.
-      Class c = Class.forName("org.apache.log4j.BasicConfigurator");
+      Class<?> c = Class.forName("org.apache.log4j.BasicConfigurator");
       Method m = c.getDeclaredMethod("configure", (Class<?>[]) null);
       Object o = m.invoke(null, (Object[]) null);
     }
@@ -975,19 +975,19 @@ public void accept(final Collection<NameAndTypes> namesAndTypes) {
           namesAndTypes.contains(
             new NameAndTypes(
               "/test_get_topic_names_and_types_one",
-              new ArrayList(Arrays.asList("rcljava/msg/UInt32")))));
+              Arrays.asList("rcljava/msg/UInt32"))));
         assertTrue(
           "topic 'test_get_topic_names_and_types_two' was not discovered",
           namesAndTypes.contains(
             new NameAndTypes(
               "/test_get_topic_names_and_types_two",
-              new ArrayList(Arrays.asList("rcljava/msg/UInt32")))));
+              Arrays.asList("rcljava/msg/UInt32"))));
         assertTrue(
           "topic 'test_get_topic_names_and_types_three' was not discovered",
           namesAndTypes.contains(
             new NameAndTypes(
               "/test_get_topic_names_and_types_three",
-              new ArrayList(Arrays.asList("rcljava/msg/Empty")))));
+              Arrays.asList("rcljava/msg/Empty"))));
       }
     };
 
@@ -1044,13 +1044,13 @@ public void accept(final Collection<NameAndTypes> namesAndTypes) {
           namesAndTypes.contains(
             new NameAndTypes(
               "/test_service_names_and_types_one",
-              new ArrayList(Arrays.asList("rcljava/srv/AddTwoInts")))));
+              Arrays.asList("rcljava/srv/AddTwoInts"))));
         assertTrue(
           "service 'test_service_names_and_types_two' was not discovered",
           namesAndTypes.contains(
             new NameAndTypes(
               "/test_service_names_and_types_two",
-              new ArrayList(Arrays.asList("rcljava/srv/AddTwoInts")))));
+              Arrays.asList("rcljava/srv/AddTwoInts"))));
       }
     };
 
@@ -1218,13 +1218,13 @@ public void accept(final Collection<NameAndTypes> local, Collection<NameAndTypes
           local.contains(
             new NameAndTypes(
               "/test_get_publisher_names_and_types_one",
-              new ArrayList(Arrays.asList("rcljava/msg/UInt32")))));
+              Arrays.asList("rcljava/msg/UInt32"))));
         assertTrue(
           "topic 'test_get_publisher_names_and_types_two' was not discovered for local node",
           local.contains(
             new NameAndTypes(
               "/test_get_publisher_names_and_types_two",
-              new ArrayList(Arrays.asList("rcljava/msg/UInt32")))));
+              Arrays.asList("rcljava/msg/UInt32"))));
 
         assertEquals(remote.size(), 2);
         assertTrue(
@@ -1232,13 +1232,13 @@ public void accept(final Collection<NameAndTypes> local, Collection<NameAndTypes
           remote.contains(
             new NameAndTypes(
               "/test_get_publisher_names_and_types_two",
-              new ArrayList(Arrays.asList("rcljava/msg/UInt32")))));
+              Arrays.asList("rcljava/msg/UInt32"))));
         assertTrue(
           "topic 'test_get_publisher_names_and_types_three' was not discovered for remote node",
           remote.contains(
             new NameAndTypes(
               "/test_get_publisher_names_and_types_three",
-              new ArrayList(Arrays.asList("rcljava/msg/UInt32")))));
+              Arrays.asList("rcljava/msg/UInt32"))));
       }
     };
 
@@ -1312,13 +1312,13 @@ public void accept(final Collection<NameAndTypes> local, Collection<NameAndTypes
           local.contains(
             new NameAndTypes(
               "/test_get_subscription_names_and_types_one",
-              new ArrayList(Arrays.asList("rcljava/msg/Empty")))));
+              Arrays.asList("rcljava/msg/Empty"))));
         assertTrue(
           "topic 'test_get_subscription_names_and_types_two' was not discovered for local node",
           local.contains(
             new NameAndTypes(
               "/test_get_subscription_names_and_types_two",
-              new ArrayList(Arrays.asList("rcljava/msg/Empty")))));
+              Arrays.asList("rcljava/msg/Empty"))));
 
         assertEquals(remote.size(), 2);
         assertTrue(
@@ -1326,13 +1326,13 @@ public void accept(final Collection<NameAndTypes> local, Collection<NameAndTypes
           remote.contains(
             new NameAndTypes(
               "/test_get_subscription_names_and_types_two",
-              new ArrayList(Arrays.asList("rcljava/msg/Empty")))));
+              Arrays.asList("rcljava/msg/Empty"))));
         assertTrue(
           "topic 'test_get_subscription_names_and_types_three' was not discovered for remote node",
           remote.contains(
             new NameAndTypes(
               "/test_get_subscription_names_and_types_three",
-              new ArrayList(Arrays.asList("rcljava/msg/Empty")))));
+              Arrays.asList("rcljava/msg/Empty"))));
       }
     };
 
@@ -1432,13 +1432,13 @@ public void accept(final Collection<NameAndTypes> local, Collection<NameAndTypes
           local.contains(
             new NameAndTypes(
               "/test_get_service_names_and_types_one",
-              new ArrayList(Arrays.asList("rcljava/srv/AddTwoInts")))));
+              Arrays.asList("rcljava/srv/AddTwoInts"))));
         assertTrue(
           "service 'test_get_service_names_and_types_two' was not discovered for local node",
           local.contains(
             new NameAndTypes(
               "/test_get_service_names_and_types_two",
-              new ArrayList(Arrays.asList("rcljava/srv/AddTwoInts")))));
+              Arrays.asList("rcljava/srv/AddTwoInts"))));
 
         assertEquals(remote.size(), 2);
         assertTrue(
@@ -1446,13 +1446,13 @@ public void accept(final Collection<NameAndTypes> local, Collection<NameAndTypes
           remote.contains(
             new NameAndTypes(
               "/test_get_service_names_and_types_two",
-              new ArrayList(Arrays.asList("rcljava/srv/AddTwoInts")))));
+              Arrays.asList("rcljava/srv/AddTwoInts"))));
         assertTrue(
           "service 'test_get_service_names_and_types_three' was not discovered for remote node",
           remote.contains(
             new NameAndTypes(
               "/test_get_service_names_and_types_three",
-              new ArrayList(Arrays.asList("rcljava/srv/AddTwoInts")))));
+              Arrays.asList("rcljava/srv/AddTwoInts"))));
       }
     };
 
@@ -1525,13 +1525,13 @@ public void accept(final Collection<NameAndTypes> local, Collection<NameAndTypes
           local.contains(
             new NameAndTypes(
               "/test_get_client_names_and_types_one",
-              new ArrayList(Arrays.asList("rcljava/srv/AddTwoInts")))));
+              Arrays.asList("rcljava/srv/AddTwoInts"))));
         assertTrue(
           "client 'test_get_client_names_and_types_two' was not discovered for local node",
           local.contains(
             new NameAndTypes(
               "/test_get_client_names_and_types_two",
-              new ArrayList(Arrays.asList("rcljava/srv/AddTwoInts")))));
+              Arrays.asList("rcljava/srv/AddTwoInts"))));
 
         assertEquals(remote.size(), 2);
         assertTrue(
@@ -1539,13 +1539,13 @@ public void accept(final Collection<NameAndTypes> local, Collection<NameAndTypes
           remote.contains(
             new NameAndTypes(
               "/test_get_client_names_and_types_two",
-              new ArrayList(Arrays.asList("rcljava/srv/AddTwoInts")))));
+              Arrays.asList("rcljava/srv/AddTwoInts"))));
         assertTrue(
           "client 'test_get_client_names_and_types_three' was not discovered for remote node",
           remote.contains(
             new NameAndTypes(
               "/test_get_client_names_and_types_three",
-              new ArrayList(Arrays.asList("rcljava/srv/AddTwoInts")))));
+              Arrays.asList("rcljava/srv/AddTwoInts"))));
       }
     };
 
diff --git a/rcljava/src/test/java/org/ros2/rcljava/parameters/AsyncParametersClientTest.java b/rcljava/src/test/java/org/ros2/rcljava/parameters/AsyncParametersClientTest.java
index 38f3e718..8ce0b5cb 100644
--- a/rcljava/src/test/java/org/ros2/rcljava/parameters/AsyncParametersClientTest.java
+++ b/rcljava/src/test/java/org/ros2/rcljava/parameters/AsyncParametersClientTest.java
@@ -77,7 +77,7 @@ public static void setupOnce() throws Exception {
     {
       // Configure log4j. Doing this dynamically so that Android does not complain about missing
       // the log4j JARs, SLF4J uses Android's native logging mechanism instead.
-      Class c = Class.forName("org.apache.log4j.BasicConfigurator");
+      Class<?> c = Class.forName("org.apache.log4j.BasicConfigurator");
       Method m = c.getDeclaredMethod("configure", (Class<?>[]) null);
       Object o = m.invoke(null, (Object[]) null);
     }
@@ -115,7 +115,9 @@ public final void testSetParameters() throws Exception {
 
     RCLFuture<List<rcl_interfaces.msg.SetParametersResult>> future =
         new RCLFuture<List<rcl_interfaces.msg.SetParametersResult>>();
-    parametersClient.setParameters(parameters, new TestConsumer(future));
+    parametersClient.setParameters(
+      parameters,
+      new TestConsumer<List<rcl_interfaces.msg.SetParametersResult>>(future));
 
     RCLJava.spinUntilComplete(node, future);
     List<rcl_interfaces.msg.SetParametersResult> setParametersResults = future.get();
@@ -143,7 +145,9 @@ public final void testGetParameters() throws Exception {
         Arrays.asList(new String[] {"foo", "bar", "baz", "foo.first", "foo.second", "foobar"});
 
     RCLFuture<List<ParameterVariant>> future = new RCLFuture<List<ParameterVariant>>();
-    parametersClient.getParameters(parameterNames, new TestConsumer(future));
+    parametersClient.getParameters(
+      parameterNames,
+      new TestConsumer<List<ParameterVariant>>(future));
 
     RCLJava.spinUntilComplete(node, future);
     assertEquals(parameters, future.get());
@@ -159,9 +163,12 @@ public final void testListParameters() throws Exception {
     node.setParameters(parameters);
 
     RCLFuture<rcl_interfaces.msg.ListParametersResult> future =
-        new RCLFuture<rcl_interfaces.msg.ListParametersResult>();
+      new RCLFuture<rcl_interfaces.msg.ListParametersResult>();
     parametersClient.listParameters(
-        Arrays.asList(new String[] {"foo", "bar"}), 10, new TestConsumer(future));
+        Arrays.asList(
+          new String[] {"foo", "bar"}),
+          10,
+          new TestConsumer<rcl_interfaces.msg.ListParametersResult>(future));
 
     RCLJava.spinUntilComplete(node, future);
     assertArrayEquals(new String[] {"foo.first", "foo.second"}, future.get().getNames());
@@ -180,7 +187,8 @@ public final void testDescribeParameters() throws Exception {
     RCLFuture<List<rcl_interfaces.msg.ParameterDescriptor>> future =
         new RCLFuture<List<rcl_interfaces.msg.ParameterDescriptor>>();
     parametersClient.describeParameters(
-        Arrays.asList(new String[] {"foo", "bar"}), new TestConsumer(future));
+        Arrays.asList(new String[] {"foo", "bar"}),
+        new TestConsumer<List<rcl_interfaces.msg.ParameterDescriptor>>(future));
 
     List<rcl_interfaces.msg.ParameterDescriptor> expected =
         Arrays.asList(new rcl_interfaces.msg.ParameterDescriptor[] {
diff --git a/rcljava/src/test/java/org/ros2/rcljava/parameters/SyncParametersClientTest.java b/rcljava/src/test/java/org/ros2/rcljava/parameters/SyncParametersClientTest.java
index 21d91688..89b3c346 100644
--- a/rcljava/src/test/java/org/ros2/rcljava/parameters/SyncParametersClientTest.java
+++ b/rcljava/src/test/java/org/ros2/rcljava/parameters/SyncParametersClientTest.java
@@ -59,7 +59,7 @@ public static void setupOnce() throws Exception {
     {
       // Configure log4j. Doing this dynamically so that Android does not complain about missing
       // the log4j JARs, SLF4J uses Android's native logging mechanism instead.
-      Class c = Class.forName("org.apache.log4j.BasicConfigurator");
+      Class<?> c = Class.forName("org.apache.log4j.BasicConfigurator");
       Method m = c.getDeclaredMethod("configure", (Class<?>[]) null);
       Object o = m.invoke(null, (Object[]) null);
     }
diff --git a/rcljava/src/test/java/org/ros2/rcljava/time/TimeSourceTest.java b/rcljava/src/test/java/org/ros2/rcljava/time/TimeSourceTest.java
index 84958b86..86bbddff 100644
--- a/rcljava/src/test/java/org/ros2/rcljava/time/TimeSourceTest.java
+++ b/rcljava/src/test/java/org/ros2/rcljava/time/TimeSourceTest.java
@@ -15,6 +15,8 @@
 
 package org.ros2.rcljava.time;
 
+import java.lang.SuppressWarnings;
+
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.assertFalse;
 
@@ -162,6 +164,8 @@ public final void testSetRosTimeIsActiveNoNode() {
     assertTrue(timeSource.getRosTimeIsActive());
   }
 
+  // there's no generic parameter type information at runtime, so we cannot write any(Consumer<T>.class)
+  @SuppressWarnings("unchecked")
   @Test
   public final void testSetRosTimeIsActiveWithNode() {
     when(mockedNode.getParameter("use_sim_time")).thenReturn(new ParameterVariant("use_sim_time", false));