KAFKA-18262: Remove DefaultPartitioner and UniformStickyPartitioner

clients/src/main/java/org/apache/kafka/clients/producer/KafkaProducer.java

@@ -326,23 +326,6 @@ public KafkaProducer(Properties properties, Serializer<K> keySerializer, Seriali
         this(Utils.propsToMap(properties), keySerializer, valueSerializer);
     }
 
-    /**
-     * Check if partitioner is deprecated and log a warning if it is.
-     */
-    @SuppressWarnings("deprecation")
-    private void warnIfPartitionerDeprecated() {
-        // Using DefaultPartitioner and UniformStickyPartitioner is deprecated, see KIP-794.
-        if (partitioner instanceof org.apache.kafka.clients.producer.internals.DefaultPartitioner) {
-            log.warn("DefaultPartitioner is deprecated.  Please clear " + ProducerConfig.PARTITIONER_CLASS_CONFIG
-                    + " configuration setting to get the default partitioning behavior");
-        }
-        if (partitioner instanceof org.apache.kafka.clients.producer.UniformStickyPartitioner) {
-            log.warn("UniformStickyPartitioner is deprecated.  Please clear " + ProducerConfig.PARTITIONER_CLASS_CONFIG
-                    + " configuration setting and set " + ProducerConfig.PARTITIONER_IGNORE_KEYS_CONFIG
-                    + " to 'true' to get the uniform sticky partitioning behavior");
-        }
-    }
-
     // visible for testing
     @SuppressWarnings({"unchecked", "this-escape"})
     KafkaProducer(ProducerConfig config,
@@ -385,7 +368,6 @@ private void warnIfPartitionerDeprecated() {
                     ProducerConfig.PARTITIONER_CLASS_CONFIG,
                     Partitioner.class,
                     Collections.singletonMap(ProducerConfig.CLIENT_ID_CONFIG, clientId));
-            warnIfPartitionerDeprecated();
             this.partitionerIgnoreKeys = config.getBoolean(ProducerConfig.PARTITIONER_IGNORE_KEYS_CONFIG);
             long retryBackoffMs = config.getLong(ProducerConfig.RETRY_BACKOFF_MS_CONFIG);
             long retryBackoffMaxMs = config.getLong(ProducerConfig.RETRY_BACKOFF_MAX_MS_CONFIG);

clients/src/main/java/org/apache/kafka/clients/producer/MockProducer.java

@@ -119,31 +119,6 @@ public MockProducer(final Cluster cluster,
         this.mockMetrics = new HashMap<>();
     }
 
-    /**
-     * Create a new mock producer with invented metadata the given autoComplete setting and key\value serializers.
-     *
-     * Equivalent to {@link #MockProducer(Cluster, boolean, Partitioner, Serializer, Serializer) new MockProducer(Cluster.empty(), autoComplete, new DefaultPartitioner(), keySerializer, valueSerializer)}
-     */
-    @SuppressWarnings("deprecation")
-    public MockProducer(final boolean autoComplete,
-                        final Serializer<K> keySerializer,
-                        final Serializer<V> valueSerializer) {
-        this(Cluster.empty(), autoComplete, new org.apache.kafka.clients.producer.internals.DefaultPartitioner(), keySerializer, valueSerializer);
-    }
-
-    /**
-     * Create a new mock producer with invented metadata the given autoComplete setting and key\value serializers.
-     *
-     * Equivalent to {@link #MockProducer(Cluster, boolean, Partitioner, Serializer, Serializer) new MockProducer(cluster, autoComplete, new DefaultPartitioner(), keySerializer, valueSerializer)}
-     */
-    @SuppressWarnings("deprecation")
-    public MockProducer(final Cluster cluster,
-                        final boolean autoComplete,
-                        final Serializer<K> keySerializer,
-                        final Serializer<V> valueSerializer) {
-        this(cluster, autoComplete, new org.apache.kafka.clients.producer.internals.DefaultPartitioner(), keySerializer, valueSerializer);
-    }
-
     /**
      * Create a new mock producer with invented metadata the given autoComplete setting, partitioner and key\value serializers.
      *
@@ -563,6 +538,9 @@ private int partition(ProducerRecord<K, V> record, Cluster cluster) {
         }
         byte[] keyBytes = keySerializer.serialize(topic, record.headers(), record.key());
         byte[] valueBytes = valueSerializer.serialize(topic, record.headers(), record.value());
+        if (partitioner == null) {
+            return this.cluster.partitionsForTopic(record.topic()).get(0).partition();
+        }
         return this.partitioner.partition(topic, record.key(), keyBytes, record.value(), valueBytes, cluster);
     }
 

clients/src/main/java/org/apache/kafka/clients/producer/Partitioner.java

@@ -44,7 +44,7 @@ public interface Partitioner extends Configurable, Closeable {
     void close();
 
     /**
-     * Note this method is only implemented in DefaultPartitioner and {@link UniformStickyPartitioner} which
+     * Note this method is only implemented in DefaultPartitioner and UniformStickyPartitioner which
      * are now deprecated. See <a href="https://cwiki.apache.org/confluence/display/KAFKA/KIP-794%3A+Strictly+Uniform+Sticky+Partitioner">KIP-794</a> for more info.
      * <p>
      * Notifies the partitioner a new batch is about to be created. When using the sticky partitioner,

clients/src/test/java/org/apache/kafka/clients/producer/MockProducerTest.java

@@ -59,7 +59,7 @@ public class MockProducerTest {
     private final String groupId = "group";
 
     private void buildMockProducer(boolean autoComplete) {
-        this.producer = new MockProducer<>(autoComplete, new MockSerializer(), new MockSerializer());
+        this.producer = new MockProducer<>(Cluster.empty(), autoComplete, null, new MockSerializer(), new MockSerializer());
     }
 
     @AfterEach
@@ -87,10 +87,16 @@ public void testPartitioner() throws Exception {
         PartitionInfo partitionInfo1 = new PartitionInfo(topic, 1, null, null, null);
         Cluster cluster = new Cluster(null, new ArrayList<>(0), asList(partitionInfo0, partitionInfo1),
                 Collections.emptySet(), Collections.emptySet());
-        MockProducer<String, String> producer = new MockProducer<>(cluster, true, new StringSerializer(), new StringSerializer());
+        MockProducer<String, String> producer = new MockProducer<>(
+            cluster,
+            true,
+            new org.apache.kafka.clients.producer.RoundRobinPartitioner(),
+            new StringSerializer(),
+            new StringSerializer()
+        );
         ProducerRecord<String, String> record = new ProducerRecord<>(topic, "key", "value");
         Future<RecordMetadata> metadata = producer.send(record);
-        assertEquals(1, metadata.get().partition(), "Partition should be correct");
+        assertEquals(0, metadata.get().partition(), "Partition should be correct");
         producer.clear();
         assertEquals(0, producer.history().size(), "Clear should erase our history");
         producer.close();
@@ -680,7 +686,7 @@ public void shouldNotThrowOnFlushProducerIfProducerIsFenced() {
     @Test
     @SuppressWarnings("unchecked")
     public void shouldThrowClassCastException() {
-        try (MockProducer<Integer, String> customProducer = new MockProducer<>(true, new IntegerSerializer(), new StringSerializer())) {
+        try (MockProducer<Integer, String> customProducer = new MockProducer<>(Cluster.empty(), true, null, new IntegerSerializer(), new StringSerializer())) {
             assertThrows(ClassCastException.class, () -> customProducer.send(new ProducerRecord(topic, "key1", "value1")));
         }
     }