diff --git a/src/main/java/io/confluent/examples/streams/MapFunctionLambdaExample.java b/src/main/java/io/confluent/examples/streams/MapFunctionLambdaExample.java
index 9b6f66c6bc..7655647cb2 100644
--- a/src/main/java/io/confluent/examples/streams/MapFunctionLambdaExample.java
+++ b/src/main/java/io/confluent/examples/streams/MapFunctionLambdaExample.java
@@ -24,7 +24,6 @@
 import org.apache.kafka.streams.StreamsConfig;
 import org.apache.kafka.streams.kstream.KStream;
 import org.apache.kafka.streams.kstream.Produced;
-import org.apache.kafka.streams.kstream.ValueMapper;
 
 import java.util.Properties;
 
@@ -121,7 +120,7 @@ public static void main(final String[] args) {
     final KStream<byte[], String> textLines = builder.stream("TextLinesTopic", Consumed.with(byteArraySerde, stringSerde));
 
     // Variant 1: using `mapValues`
-    final KStream<byte[], String> uppercasedWithMapValues = textLines.mapValues((ValueMapper<String, String>) String::toLowerCase);
+    final KStream<byte[], String> uppercasedWithMapValues = textLines.mapValues(v -> v.toLowerCase());
 
     // Write (i.e. persist) the results to a new Kafka topic called "UppercasedTextLinesTopic".
     //
diff --git a/src/test/java/io/confluent/examples/streams/FanoutLambdaIntegrationTest.java b/src/test/java/io/confluent/examples/streams/FanoutLambdaIntegrationTest.java
index abcc15022f..4dc7566b62 100644
--- a/src/test/java/io/confluent/examples/streams/FanoutLambdaIntegrationTest.java
+++ b/src/test/java/io/confluent/examples/streams/FanoutLambdaIntegrationTest.java
@@ -27,7 +27,6 @@
 import org.apache.kafka.streams.StreamsBuilder;
 import org.apache.kafka.streams.StreamsConfig;
 import org.apache.kafka.streams.kstream.KStream;
-import org.apache.kafka.streams.kstream.ValueMapper;
 import org.junit.BeforeClass;
 import org.junit.ClassRule;
 import org.junit.Test;
@@ -94,8 +93,8 @@ public void shouldFanoutTheInput() throws Exception {
     streamsConfiguration.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest");
 
     KStream<byte[], String> stream1 = builder.stream(inputTopicA);
-    KStream<byte[], String> stream2 = stream1.mapValues((ValueMapper<String, String>) String::toUpperCase);
-    KStream<byte[], String> stream3 = stream1.mapValues((ValueMapper<String, String>) String::toLowerCase);
+    KStream<byte[], String> stream2 = stream1.mapValues((v -> v.toUpperCase()));
+    KStream<byte[], String> stream3 = stream1.mapValues(v -> v.toLowerCase());
     stream2.to(outputTopicB);
     stream3.to(outputTopicC);
 
diff --git a/src/test/java/io/confluent/examples/streams/MapFunctionLambdaIntegrationTest.java b/src/test/java/io/confluent/examples/streams/MapFunctionLambdaIntegrationTest.java
index 37dd7ecee0..d88c70fdb6 100644
--- a/src/test/java/io/confluent/examples/streams/MapFunctionLambdaIntegrationTest.java
+++ b/src/test/java/io/confluent/examples/streams/MapFunctionLambdaIntegrationTest.java
@@ -27,7 +27,6 @@
 import org.apache.kafka.streams.StreamsBuilder;
 import org.apache.kafka.streams.StreamsConfig;
 import org.apache.kafka.streams.kstream.KStream;
-import org.apache.kafka.streams.kstream.ValueMapper;
 import org.junit.BeforeClass;
 import org.junit.ClassRule;
 import org.junit.Test;
@@ -76,7 +75,7 @@ public void shouldUppercaseTheInput() throws Exception {
     streamsConfiguration.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest");
 
     KStream<byte[], String> input = builder.stream(inputTopic);
-    KStream<byte[], String> uppercased = input.mapValues((ValueMapper<String, String>) String::toUpperCase);
+    KStream<byte[], String> uppercased = input.mapValues(v -> v.toUpperCase());
     uppercased.to(outputTopic);
 
     KafkaStreams streams = new KafkaStreams(builder.build(), streamsConfiguration);
diff --git a/src/test/java/io/confluent/examples/streams/MixAndMatchLambdaIntegrationTest.java b/src/test/java/io/confluent/examples/streams/MixAndMatchLambdaIntegrationTest.java
index d0be975ce6..68c7c1acb7 100644
--- a/src/test/java/io/confluent/examples/streams/MixAndMatchLambdaIntegrationTest.java
+++ b/src/test/java/io/confluent/examples/streams/MixAndMatchLambdaIntegrationTest.java
@@ -30,7 +30,6 @@
 import org.apache.kafka.streams.kstream.KStream;
 import org.apache.kafka.streams.kstream.Transformer;
 import org.apache.kafka.streams.kstream.TransformerSupplier;
-import org.apache.kafka.streams.kstream.ValueMapper;
 import org.apache.kafka.streams.processor.ProcessorContext;
 import org.apache.kafka.streams.processor.ProcessorSupplier;
 import org.junit.BeforeClass;
@@ -145,7 +144,7 @@ public void shouldAnonymizeTheInput() throws Exception {
 
     KStream<byte[], String> input = builder.stream(inputTopic);
     KStream<byte[], String> uppercasedAndAnonymized = input
-        .mapValues((ValueMapper<String, String>) String::toUpperCase)
+        .mapValues(v -> v.toUpperCase())
         .transform(AnonymizeIpAddressTransformer::new);
     uppercasedAndAnonymized.to(outputTopic);